Enki
Motorhead
11-3-2016
Updates abound, see text with this color to find out what's changed.
Original Post:
Some of you may know that I have smoke coming out of my valve cover; a sure sign that the rings are done. This thread is (primarily) to chronicle my little experiment (and secondarily to learn new things).
Before this gets in depth, here's a TLDR:
Great, now that that's out of the way, some points of explanation as to why before we get to the what:
Explanation
1. Yes, this car is my daily driver, but no, I'm not worried about reliability too much. I work from home and have access to use vehicles I don't own.
2. The primary reason I'm doing this weird ass build is to test a couple of theories that I will get to in the Reasoning section; this is in preparation for a much bigger build not involving the Mazda.
3. It will take me quite a while to finish. I'm not made of money, so things will take time to purchase/pay off. Even after the engine is built, it will take some time before I'm driving it again because of fabrication and other stuff that needs to happen.
Great, now on to the major changes compared to a “standard build:”
Major Changes
1. Destroked from 94mm to 83.1mm (2.0 liters final displacement)
2. Stock bore will be kept to help with high RPM breathing and cylinder wall thickness/thermal mass
3. Custom grind from scratch cams are unlikely to happen, but someone is investigating alternatives that I might wind up running; otherwise, I will be using stock cams with a custom regrind (no welding)
4. Extensive runner work will not be done on the intake side, as changing the runner size can actually hurt drive-ability without VCTS present; going to just have gasket matching and heavy bowl work done to open up more flow along with some minor feathering/knife edging on the intake side, while the hotside will get bowl work and full hogging into the gasket match for maximized exhaust flow
5. Full corn (E85) + tree bark (meth); twin 1500 cc injectors for 6th port are en route. I will have enough fuel for close to 430 to the wheel, depending
6. Very high static compression ratio (for a turbo build); 12.5:1 pistons are on deck; these would be 14:1 compression on a non destroke build; stock pistons on the destroke would be 8.5:1.
7. Stock turbo boost levels were an original goal, but it is likely I will need to increase boost to hit the same airflow due to the reduction in displacement; I'll do this sparingly, but I'm going to start with a 10 PSI spring. Everything is set up for maximum flow for efficient power, so my boost requirements for a given power level should be lower, but will also likely limit my maximum possible power (which I'm ok with).
8. Electric water pump and supporting modifications to the cooling system like removing the thermostat; electric water pumps will lose a lot of flow if the head pressure climbs, so it's best to run them as open to flow as possible
9. Improved stock oil cooling via dedicated water flow to the oil cooler that only sees the radiator vs hot engine water.
10. Custom TMIC for sleeper look and improved radiator airflow/cooling after I get data on using a Corksport TMIC; not going to happen immediately, but will eventually happen.
11. Full 3.5" exhaust to increase breathing efficiency out the back
12. Ditching the stock radiator and fan setup for heat rejection coated Koyorad and a pair of high flow fans (two dual speed fans totaling 2900 CFM at full nuts)
13. Lightened internals/FW to improve throttle response and rev matching; the pistons are slightly lighter than stock, and the crank is 40% lighter than stock; the flywheel is aluminum, but the pressure plate and clutch disk will be stock.
14. Sleeper engine bay
15. ???
16. Profit
Reasoning
1. De-stroked to increase volumetric efficiency higher up in the RPM band, thus reducing power drop off I was experiencing (which as it turns out was mostly due to turbo hotside sizing), and should help with MPG. Hopefully the drastic increase in rod ratio will also reduce NVH with BSD. This will also limit how much timing can be run due to piston dwell @ TDC, allowing a longer spray window before overrunning and getting misfires.
2. Stock bore kept for thermal mass, reliability, and again, MPG. Reducing displacement without shrinking bore will help with high RPM breathing.
3. The cams are a stock core regrind with no welding that have duration maximized at the cost of lift; per information available about our head, the decrease in flow would only be on the intake side and is equivalent to a fart in a hurricane. The duration is limited based on the information I found regarding injector duty cycle and how it's calculated (see here: http://mazdaspeeds.org/index.php?threads/the-disi-mzr-fuel-system-warning-science-heavy.648/ )
4. Mostly exhaust and bowl work to improve efficiency and reduce reversion in the higher RPMs. The goal is to make the most power I can as efficiently as I can (i.e. least boost possible)
5. Staying with full corn, despite possible power increases due to improvement in fueling headroom because of major change 6; with the changes to ethanol availability, I might wind up going to E50 by no choice of my own.
6. E85 is prevalent where I live, so I'm going to make the most of it; this means maximizing compression in order to squeeze (pardon the pun) the most efficiency out of the fuel. This will help with MPG and power at lower boost levels, as well as power up top in the rev band.
7. Running a really high compression ratio will probably reduce the amount of boost I can run, even on E85, but this doesn't bother me so much. Again, going to see what this setup does, and with any luck make more power than what I was on stock block.
8. Electric water pump is for a couple of reasons; being able to have the same velocity/volume of water flowing through the engine at all times (especially at idle), and to make it possible to more rapidly cool down the engine during track days when shut down. It will also help keep the stock water pump from cavitating at higher RPMs and further reducing cooling efficiency when it's needed most. This will be controlled by the Megasquirt ECU via PWM.
9. Keeping the stock oil cooler but bypassing its feed from the block to be fed directly from the radiator should mean I won't need aux oil cooling
10. TMICs are less laggy, don't weigh as much, don't block the radiator (arguably important in the desert), and aren't TOO efficient; this is important because of all the alcohol I'll be spraying into the cylinder, not including meth which will bring temps down further. Too cold, and it runs like shit.
11. Increasing overall airflow means touching everything, including the exhaust. The exhaust system will be a fully custom built turboback with the first downpipe section being stainless and the rest mild steel; vbands will be the connector of choice.
12. More radiator = better cooling. Bigger and dual fans will help with that as well, and a real *adjustable* thermostat control (by directly controlling water flow through the engine rather than using an actual thermostat) for it will be nice. The fans I have my eye on are two speed; low will kick on via temp sensor and be run by the Megasquirt and/or AC (depending on if I can get that to work)
13. New crankshaft is lighter than stock, as is the new clutch and flywheel assembly. My motivation for this will be explained in the Goals section.
14. Nothing is better than shitstomping someone who knows these cars, popping the hood and having them ask how I got it so fast when it looks so stock. Fucking glorious.
15. ??????
16. Yes please.
Goals
To get a feel for why I'm doing this, check out the following video, and keep a close eye on the tach (original video taken down):
Compare this to a non-response build:
Realistically, I'd like to have traction in all gears (including first), as well as having close to or over 400 WHP as is feasible (I'd like more if it will support it, but even 400 WHP isn't a goal). For whatever reason, I was not able to get VersaTune to bring the boost down in 1st and 2nd enough to keep traction, which hurt me pretty bad ET wise at the strip; thus, I gained ~40 WHP but lost .4 on my 60' and had TERRIBLE wheel hop issues in both 1st and 2nd.
Honestly, I'm not terribly worried if I get to the power goal or not, as I'll be able to make up some lost power with RPM and mechanical advantage; more on that later. Obviously, I don't want it to be a dog, and I will tune it so it isn't, even if that hampers my RPM goals somewhat.
The Science
Here's where shit goes off the deep end; I don't claim all of this is correct, but I've spent considerable time researching this and have pulled the vast majority of formula from trusted sources (like Garret and Borg Warner white papers, etc).
Let's start with gearing (ignore drive shaft RPM in pic, as it doesn't apply):
As everyone who's done a 60-100 pull knows, 4th gear ends at 100 MPH when you shift at 6k (give or take, depending on tire size). Well, what if you could do that same pull in 3rd?
It's a similar benefit to running diesel gears, only you don't need Hulk levels of torque or a modified transmission to do it.
"Well gosh, Enki; that's swell...but why?"
Glad you asked, but I hope you have your thinking cap on. Take a look at this:
As you can see on the left side, there's a bit of speed gained when you shift higher (duh). Shifting at 8,000 RPM instead of 6000 RPM nets you a 33.33% increase in MPH between shifts; as the gear goes higher, this speed gain becomes considerable.
My best speed at the dragstrip was 120 MPH (prior best was 117); this was done not with a significant boost/timing/fuel change, but with a 500 RPM bump in redline.
On the right side of the picture, you can see that I'm anticipating giving up some torque; I don't really have to down low (because motor will be built), but I'm betting I won't have the fuel to hold more than say 300 WTQ @ 8k, especially considering I wasn't able to hold it on stock displacement @ 7k. Anywho, assuming I take a 14.29% loss in torque (at 6k RPM), shifting at 8k RPM nets me a 35.45% wheel torque gain for 11 MPH over shifting to 2nd...And that's how you should (probably) interpret the data. By the time you'd get to 4th gear, you'd already rack up 53.5 MPH of somewhat significant mechanical advantage. The downside is you'd be down on axle torque in 1st compared to the original number... But let's face it: Who is on street tires and doesn't make enough power to blow the tires off in first?
"That's got to be bullshit, Enki."
Well now, hold on a sec. I have an anecdote that fits this criteria. I once ran into a friend on the street (in Mexico, of course...small world), and had a friendly race with them. It couldn't be more even if we were parked next to each other. They got the jump, but I was able to reel them back in on every shift until I had put a bumper length on them; and for no reason other than I shifted a couple hundred RPM later.
Also, there's this video which at least partially backs up my ideas on this build (science alert):
If anyone is interested, I have some ancillary data pertaining to tire size effect on MPH and RPM drop at specific shift RPMs:
This is 3000 RPM in 6th gear, by the way; horizontal is width, vertical is aspect ratio (assuming 18" wheel):
The tire size info is useful because I can use it to fine tune my RPM to MPH goals very easily; reduce the size a bit to gain effective torque at the wheel if I'm not going through the traps at redline, or increase the size to reduce torque and gain MPH if I'm hitting rev limiter a bit before the traps.
Shift/RPM info:
And here's some graphical data to help interpret the above (non tire size) info (click for big):
Misc Tech Stuff
Displacement goes to 2 liters, on the dot; rod ratio increases from 1.6 to 1.92:1 as well, assuming linear transference of stroke to rod length; this will also reduce peak rod angle from 17.75 degrees to 15.09 degrees (which is a reduction of about 17%) and should also help with side loading of the pistons. This will, of course, hurt torque/power production until an RPM threshold is reached, but I'm not really worried about that.
Another side effect of stroke reduction is the reduction in compression ratio; assuming stock pistons are used and stroke reduction is added to rod length, the effective static compression ratio will drop from 9.5:1 to 8.5:1. I've already addressed this by adding a shitload of dome to the custom pistons, which has brought compression back up to 12.5:1; perfect for corn.
Upgrades
Bigger big turbo? Don't mind if I do!
I'll be going to the 7163 from the 6758 for a couple of reasons. It will spool faster, and it will flow more air more efficiently on both the hot (larger hotside wheel *AND* larger AR on the hotside for one) and cold sides, as seen below.
*Note: The following chart is deprecated and does not apply to my build any longer; only for comparison of the two turbos*
This is how the planned boost curve (20 psi peak reverse taper holding 300 WTQ) looks on the compressor map on the 7163 (point 1 = 3k RPM, point 6 = 8k RPM):
*Note: The following chart is deprecated and does not apply to my build any longer; only for comparison of the two turbos*
And if I kept the 6758 (point 1 = 3k RPM, point 6 = 8k RPM):
Just makes sense to upgrade, especially considering the 7163 will spool faster than the 6758, even on stock block. With the reduction in displacement, I'll happily take any natural increase in spool I can get.
3.5" exhaust!
Downpipe will be 3..25" from the turbo and expand to 3.5" after the short downpipe section; this should help with both spool and top end flow. Ancillary research suggests hit or miss power improvements over 3" exhaust, but seems to be largely variable dependent (setup, air quality, etc). Might as well give it a shot. Below is exhaust size/area/estimated HP supported numbers, mostly applicable to NA engines but still relevant here:
As you can see, the 3.5" exhaust has about 35% more area for flow, and should at the very least more easily support ~400 whp.
I'm also going to redo my crankcase evac setup to dump right to exhaust so I don't have to empty a catch can anymore; should also allow for more overall venting, if set up correctly (will probably need advice on where to put this). It's also going to be full vband, so I'll be able to test/compare muffler/dump setups.
Drivetrain upgrades!
Shifter fork pads, and a Quaife helical LSD are in the car.
3.5 BAR MAP!
Don't really see myself going past 30 PSI anytime soon anyways (but I might need to depending), especially not with the littlebig turbo.
HIDs!
55 watt low beam and 35 watt fogs, both in 4300k.
TMIC!
Picked up a Corksport unit, but ultimately, I'm probably going to run a custom TMIC built by Bell Intercoolers down the road; the core I have picked out has more core and surface area than a TR8, with higher overall flow to match.
Radiator and fan!
The Koyorad radiator has provisions for temp sensor, which will come in handy for the 2900 CFMs of fan that will be going on the back of it.
Intake mani!
Corksport and/or someone else needs to get their shit together though.
External water pump!
If shit ever goes wrong, will be an easy swap. The impeller is going to be cut off the stock pump, and the tstat housing will be replaced with a huge AN fitting or simple pipe outlet unit. I don't think I'm going to need a tstat, but if I do, I can add one later.
Supplemental oil cooling!
Don't think I'll need this after all, but will know more after testing the initial setup.
Aluminum skid plate!
Aero is FTW. I'll probably tape up parts of it with aluminum tape as well, just cause.
LED lights!
Aaron's favorite! +50 whp!
Modified stock valve cover!
No breather cap, but a decent sized fitting will be screwed in place of the stock breather tube thingy (the stock tube is just pressed in, and came out easily). I'll also be addressing the serious lack of flow coming from the VC breather due to the stock design.
Under-driven pulleys!
Since I idle 42% higher already (1k-1100 RPM), a 15-20% underdrive won't hurt anything. This means dropping a 3" pulley on the alt (which actually still has it spinning faster at 1k RPM idle than it would at 750 RPM idle with a stock pulley), and reduces alternator RPM from ~23,000 @ 9,000 RPM down to 18,000.
Other Plans
I'm going to get brand new of the following items in addition to everything already mentioned above (italics items are already obtained):
Headlight housings (mine are proper fucked from sand and sun)
Clutch slave
Throwout bearing
Throwout fork
Coolant/etc hoses (silicone where available)
Boost tubes (silicone where available)
PS cooler (mine is old, time to upgrade)
Power steering pump
AC compressor
Tensioner pulley
Higher amperage alternator, might have the stock one tested too!
Stuff to anodize:
Intake piping
TMIC cold pipe (after porting/polishing/gasket matching), provided I even use it going forward.
Stuff to ceramic coat:
Downpipe
Valve cover
Stuff to get heat rejection coating:
Intercooler
Radiator
AC Condenser
Community Benefits
Well, when this is done, we should have the following:
Source for stroke/destroke drop in crankshaft
Source for high output alternators (possibly)
Possibly another option for autox racers as far as build plans go
Misc
What else should I consider replacing?
Is there anything else that would be worth testing (that isn't nitrous or nitro-methane or anything completely retarded)?
Does anyone have any input on any part of this list/post? Math, experiences, etc?
Any information that might even be remotely useful to the platform (like cam/crank blueprints) will be posted here for the community at large to do with what they will, as will all knowledge gained from this little endeavor; this depends entirely upon the success/failure of this project, however.
Updates abound, see text with this color to find out what's changed.
Original Post:
Some of you may know that I have smoke coming out of my valve cover; a sure sign that the rings are done. This thread is (primarily) to chronicle my little experiment (and secondarily to learn new things).
Before this gets in depth, here's a TLDR:
Great, now that that's out of the way, some points of explanation as to why before we get to the what:
Explanation
1. Yes, this car is my daily driver, but no, I'm not worried about reliability too much. I work from home and have access to use vehicles I don't own.
2. The primary reason I'm doing this weird ass build is to test a couple of theories that I will get to in the Reasoning section; this is in preparation for a much bigger build not involving the Mazda.
3. It will take me quite a while to finish. I'm not made of money, so things will take time to purchase/pay off. Even after the engine is built, it will take some time before I'm driving it again because of fabrication and other stuff that needs to happen.
Great, now on to the major changes compared to a “standard build:”
Major Changes
1. Destroked from 94mm to 83.1mm (2.0 liters final displacement)
2. Stock bore will be kept to help with high RPM breathing and cylinder wall thickness/thermal mass
3. Custom grind from scratch cams are unlikely to happen, but someone is investigating alternatives that I might wind up running; otherwise, I will be using stock cams with a custom regrind (no welding)
4. Extensive runner work will not be done on the intake side, as changing the runner size can actually hurt drive-ability without VCTS present; going to just have gasket matching and heavy bowl work done to open up more flow along with some minor feathering/knife edging on the intake side, while the hotside will get bowl work and full hogging into the gasket match for maximized exhaust flow
5. Full corn (E85) + tree bark (meth); twin 1500 cc injectors for 6th port are en route. I will have enough fuel for close to 430 to the wheel, depending
6. Very high static compression ratio (for a turbo build); 12.5:1 pistons are on deck; these would be 14:1 compression on a non destroke build; stock pistons on the destroke would be 8.5:1.
7. Stock turbo boost levels were an original goal, but it is likely I will need to increase boost to hit the same airflow due to the reduction in displacement; I'll do this sparingly, but I'm going to start with a 10 PSI spring. Everything is set up for maximum flow for efficient power, so my boost requirements for a given power level should be lower, but will also likely limit my maximum possible power (which I'm ok with).
8. Electric water pump and supporting modifications to the cooling system like removing the thermostat; electric water pumps will lose a lot of flow if the head pressure climbs, so it's best to run them as open to flow as possible
9. Improved stock oil cooling via dedicated water flow to the oil cooler that only sees the radiator vs hot engine water.
10. Custom TMIC for sleeper look and improved radiator airflow/cooling after I get data on using a Corksport TMIC; not going to happen immediately, but will eventually happen.
11. Full 3.5" exhaust to increase breathing efficiency out the back
12. Ditching the stock radiator and fan setup for heat rejection coated Koyorad and a pair of high flow fans (two dual speed fans totaling 2900 CFM at full nuts)
13. Lightened internals/FW to improve throttle response and rev matching; the pistons are slightly lighter than stock, and the crank is 40% lighter than stock; the flywheel is aluminum, but the pressure plate and clutch disk will be stock.
14. Sleeper engine bay
15. ???
16. Profit
Reasoning
1. De-stroked to increase volumetric efficiency higher up in the RPM band, thus reducing power drop off I was experiencing (which as it turns out was mostly due to turbo hotside sizing), and should help with MPG. Hopefully the drastic increase in rod ratio will also reduce NVH with BSD. This will also limit how much timing can be run due to piston dwell @ TDC, allowing a longer spray window before overrunning and getting misfires.
2. Stock bore kept for thermal mass, reliability, and again, MPG. Reducing displacement without shrinking bore will help with high RPM breathing.
3. The cams are a stock core regrind with no welding that have duration maximized at the cost of lift; per information available about our head, the decrease in flow would only be on the intake side and is equivalent to a fart in a hurricane. The duration is limited based on the information I found regarding injector duty cycle and how it's calculated (see here: http://mazdaspeeds.org/index.php?threads/the-disi-mzr-fuel-system-warning-science-heavy.648/ )
4. Mostly exhaust and bowl work to improve efficiency and reduce reversion in the higher RPMs. The goal is to make the most power I can as efficiently as I can (i.e. least boost possible)
5. Staying with full corn, despite possible power increases due to improvement in fueling headroom because of major change 6; with the changes to ethanol availability, I might wind up going to E50 by no choice of my own.
6. E85 is prevalent where I live, so I'm going to make the most of it; this means maximizing compression in order to squeeze (pardon the pun) the most efficiency out of the fuel. This will help with MPG and power at lower boost levels, as well as power up top in the rev band.
7. Running a really high compression ratio will probably reduce the amount of boost I can run, even on E85, but this doesn't bother me so much. Again, going to see what this setup does, and with any luck make more power than what I was on stock block.
8. Electric water pump is for a couple of reasons; being able to have the same velocity/volume of water flowing through the engine at all times (especially at idle), and to make it possible to more rapidly cool down the engine during track days when shut down. It will also help keep the stock water pump from cavitating at higher RPMs and further reducing cooling efficiency when it's needed most. This will be controlled by the Megasquirt ECU via PWM.
9. Keeping the stock oil cooler but bypassing its feed from the block to be fed directly from the radiator should mean I won't need aux oil cooling
10. TMICs are less laggy, don't weigh as much, don't block the radiator (arguably important in the desert), and aren't TOO efficient; this is important because of all the alcohol I'll be spraying into the cylinder, not including meth which will bring temps down further. Too cold, and it runs like shit.
11. Increasing overall airflow means touching everything, including the exhaust. The exhaust system will be a fully custom built turboback with the first downpipe section being stainless and the rest mild steel; vbands will be the connector of choice.
12. More radiator = better cooling. Bigger and dual fans will help with that as well, and a real *adjustable* thermostat control (by directly controlling water flow through the engine rather than using an actual thermostat) for it will be nice. The fans I have my eye on are two speed; low will kick on via temp sensor and be run by the Megasquirt and/or AC (depending on if I can get that to work)
13. New crankshaft is lighter than stock, as is the new clutch and flywheel assembly. My motivation for this will be explained in the Goals section.
14. Nothing is better than shitstomping someone who knows these cars, popping the hood and having them ask how I got it so fast when it looks so stock. Fucking glorious.
15. ??????
16. Yes please.
Goals
To get a feel for why I'm doing this, check out the following video, and keep a close eye on the tach (original video taken down):
Compare this to a non-response build:
Realistically, I'd like to have traction in all gears (including first), as well as having close to or over 400 WHP as is feasible (I'd like more if it will support it, but even 400 WHP isn't a goal). For whatever reason, I was not able to get VersaTune to bring the boost down in 1st and 2nd enough to keep traction, which hurt me pretty bad ET wise at the strip; thus, I gained ~40 WHP but lost .4 on my 60' and had TERRIBLE wheel hop issues in both 1st and 2nd.
Honestly, I'm not terribly worried if I get to the power goal or not, as I'll be able to make up some lost power with RPM and mechanical advantage; more on that later. Obviously, I don't want it to be a dog, and I will tune it so it isn't, even if that hampers my RPM goals somewhat.
The Science
Here's where shit goes off the deep end; I don't claim all of this is correct, but I've spent considerable time researching this and have pulled the vast majority of formula from trusted sources (like Garret and Borg Warner white papers, etc).
Let's start with gearing (ignore drive shaft RPM in pic, as it doesn't apply):
As everyone who's done a 60-100 pull knows, 4th gear ends at 100 MPH when you shift at 6k (give or take, depending on tire size). Well, what if you could do that same pull in 3rd?
It's a similar benefit to running diesel gears, only you don't need Hulk levels of torque or a modified transmission to do it.
"Well gosh, Enki; that's swell...but why?"
Glad you asked, but I hope you have your thinking cap on. Take a look at this:
As you can see on the left side, there's a bit of speed gained when you shift higher (duh). Shifting at 8,000 RPM instead of 6000 RPM nets you a 33.33% increase in MPH between shifts; as the gear goes higher, this speed gain becomes considerable.
My best speed at the dragstrip was 120 MPH (prior best was 117); this was done not with a significant boost/timing/fuel change, but with a 500 RPM bump in redline.
On the right side of the picture, you can see that I'm anticipating giving up some torque; I don't really have to down low (because motor will be built), but I'm betting I won't have the fuel to hold more than say 300 WTQ @ 8k, especially considering I wasn't able to hold it on stock displacement @ 7k. Anywho, assuming I take a 14.29% loss in torque (at 6k RPM), shifting at 8k RPM nets me a 35.45% wheel torque gain for 11 MPH over shifting to 2nd...And that's how you should (probably) interpret the data. By the time you'd get to 4th gear, you'd already rack up 53.5 MPH of somewhat significant mechanical advantage. The downside is you'd be down on axle torque in 1st compared to the original number... But let's face it: Who is on street tires and doesn't make enough power to blow the tires off in first?
"That's got to be bullshit, Enki."
Well now, hold on a sec. I have an anecdote that fits this criteria. I once ran into a friend on the street (in Mexico, of course...small world), and had a friendly race with them. It couldn't be more even if we were parked next to each other. They got the jump, but I was able to reel them back in on every shift until I had put a bumper length on them; and for no reason other than I shifted a couple hundred RPM later.
Also, there's this video which at least partially backs up my ideas on this build (science alert):
If anyone is interested, I have some ancillary data pertaining to tire size effect on MPH and RPM drop at specific shift RPMs:
This is 3000 RPM in 6th gear, by the way; horizontal is width, vertical is aspect ratio (assuming 18" wheel):
The tire size info is useful because I can use it to fine tune my RPM to MPH goals very easily; reduce the size a bit to gain effective torque at the wheel if I'm not going through the traps at redline, or increase the size to reduce torque and gain MPH if I'm hitting rev limiter a bit before the traps.
Shift/RPM info:
And here's some graphical data to help interpret the above (non tire size) info (click for big):
Misc Tech Stuff
Displacement goes to 2 liters, on the dot; rod ratio increases from 1.6 to 1.92:1 as well, assuming linear transference of stroke to rod length; this will also reduce peak rod angle from 17.75 degrees to 15.09 degrees (which is a reduction of about 17%) and should also help with side loading of the pistons. This will, of course, hurt torque/power production until an RPM threshold is reached, but I'm not really worried about that.
Another side effect of stroke reduction is the reduction in compression ratio; assuming stock pistons are used and stroke reduction is added to rod length, the effective static compression ratio will drop from 9.5:1 to 8.5:1. I've already addressed this by adding a shitload of dome to the custom pistons, which has brought compression back up to 12.5:1; perfect for corn.
Upgrades
Bigger big turbo? Don't mind if I do!
I'll be going to the 7163 from the 6758 for a couple of reasons. It will spool faster, and it will flow more air more efficiently on both the hot (larger hotside wheel *AND* larger AR on the hotside for one) and cold sides, as seen below.
*Note: The following chart is deprecated and does not apply to my build any longer; only for comparison of the two turbos*
This is how the planned boost curve (20 psi peak reverse taper holding 300 WTQ) looks on the compressor map on the 7163 (point 1 = 3k RPM, point 6 = 8k RPM):
*Note: The following chart is deprecated and does not apply to my build any longer; only for comparison of the two turbos*
And if I kept the 6758 (point 1 = 3k RPM, point 6 = 8k RPM):
Just makes sense to upgrade, especially considering the 7163 will spool faster than the 6758, even on stock block. With the reduction in displacement, I'll happily take any natural increase in spool I can get.
3.5" exhaust!
Downpipe will be 3..25" from the turbo and expand to 3.5" after the short downpipe section; this should help with both spool and top end flow. Ancillary research suggests hit or miss power improvements over 3" exhaust, but seems to be largely variable dependent (setup, air quality, etc). Might as well give it a shot. Below is exhaust size/area/estimated HP supported numbers, mostly applicable to NA engines but still relevant here:
As you can see, the 3.5" exhaust has about 35% more area for flow, and should at the very least more easily support ~400 whp.
I'm also going to redo my crankcase evac setup to dump right to exhaust so I don't have to empty a catch can anymore; should also allow for more overall venting, if set up correctly (will probably need advice on where to put this). It's also going to be full vband, so I'll be able to test/compare muffler/dump setups.
Drivetrain upgrades!
Shifter fork pads, and a Quaife helical LSD are in the car.
3.5 BAR MAP!
Don't really see myself going past 30 PSI anytime soon anyways (but I might need to depending), especially not with the littlebig turbo.
HIDs!
55 watt low beam and 35 watt fogs, both in 4300k.
TMIC!
Picked up a Corksport unit, but ultimately, I'm probably going to run a custom TMIC built by Bell Intercoolers down the road; the core I have picked out has more core and surface area than a TR8, with higher overall flow to match.
Radiator and fan!
The Koyorad radiator has provisions for temp sensor, which will come in handy for the 2900 CFMs of fan that will be going on the back of it.
Intake mani!
Corksport and/or someone else needs to get their shit together though.
External water pump!
If shit ever goes wrong, will be an easy swap. The impeller is going to be cut off the stock pump, and the tstat housing will be replaced with a huge AN fitting or simple pipe outlet unit. I don't think I'm going to need a tstat, but if I do, I can add one later.
Supplemental oil cooling!
Don't think I'll need this after all, but will know more after testing the initial setup.
Aluminum skid plate!
Aero is FTW. I'll probably tape up parts of it with aluminum tape as well, just cause.
LED lights!
Aaron's favorite! +50 whp!
Modified stock valve cover!
No breather cap, but a decent sized fitting will be screwed in place of the stock breather tube thingy (the stock tube is just pressed in, and came out easily). I'll also be addressing the serious lack of flow coming from the VC breather due to the stock design.
Under-driven pulleys!
Since I idle 42% higher already (1k-1100 RPM), a 15-20% underdrive won't hurt anything. This means dropping a 3" pulley on the alt (which actually still has it spinning faster at 1k RPM idle than it would at 750 RPM idle with a stock pulley), and reduces alternator RPM from ~23,000 @ 9,000 RPM down to 18,000.
Other Plans
I'm going to get brand new of the following items in addition to everything already mentioned above (italics items are already obtained):
Headlight housings (mine are proper fucked from sand and sun)
Clutch slave
Throwout bearing
Throwout fork
Coolant/etc hoses (silicone where available)
Boost tubes (silicone where available)
PS cooler (mine is old, time to upgrade)
Power steering pump
AC compressor
Tensioner pulley
Higher amperage alternator, might have the stock one tested too!
Stuff to anodize:
Intake piping
TMIC cold pipe (after porting/polishing/gasket matching), provided I even use it going forward.
Stuff to ceramic coat:
Downpipe
Valve cover
Stuff to get heat rejection coating:
Intercooler
Radiator
AC Condenser
Community Benefits
Well, when this is done, we should have the following:
Source for stroke/destroke drop in crankshaft
Source for high output alternators (possibly)
Possibly another option for autox racers as far as build plans go
Misc
What else should I consider replacing?
Is there anything else that would be worth testing (that isn't nitrous or nitro-methane or anything completely retarded)?
Does anyone have any input on any part of this list/post? Math, experiences, etc?
Any information that might even be remotely useful to the platform (like cam/crank blueprints) will be posted here for the community at large to do with what they will, as will all knowledge gained from this little endeavor; this depends entirely upon the success/failure of this project, however.
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