Alright so the new S5 is out but im just curious if anyone has actually got one and used it yet? I was panning on an upgraded turbo in the next year or so and now am deciding between the S4 or S5?
BNR S5
- Thread starter StreetSpeed6
- Start date
Two documented members of the community have S5's at the moment, both Gen2 speed3's that were dyno tuned at the same place with relatively different setups and both made about 525 whp with port injection on E85 and 450 whp on 93. The S4 is generally known to support at least 450 on E85 (you'll need a 6th port kit at the minimum), up to the high 400's. Both turbos spool at about 4000 RPM's. One consideration is the S5 is EWG only, so there's not just the added cost of the turbo itself, you'll need a dump tube and EWG as well.
What are the ring gaps on your motor set at out of curiosity, and what head studs are you using? From a practical standpoint, the S5 is going to put a lot more heat into the engine, due to the size difference in the compressor wheel alone. If you're doing track work, I would recommend an oil cooler with either turbo, and an upgraded radiator with the S5, possibly both. If you're doing primarily autocross, I wouldn't recommend either. I would go with an S3 for that. For street-only use for sure I would go with the S5. The power is going to feel way over the top and way more fun. It's a very expensive route though.
What are the ring gaps on your motor set at out of curiosity, and what head studs are you using? From a practical standpoint, the S5 is going to put a lot more heat into the engine, due to the size difference in the compressor wheel alone. If you're doing track work, I would recommend an oil cooler with either turbo, and an upgraded radiator with the S5, possibly both. If you're doing primarily autocross, I wouldn't recommend either. I would go with an S3 for that. For street-only use for sure I would go with the S5. The power is going to feel way over the top and way more fun. It's a very expensive route though.
I haven’t had my motor built yet actually so it’s another main consideration of whether or not to do the motor or turbo first. Either way it is going to be mainly used as a DD (For now anyways....lol) and my goal for my ms6 is to slowly just keep building it as I have the money and see what she can do haha
[doublepost=1524931048][/doublepost]My mods aren’t too long but basically 3” catless downpipe, CS hpfp, custom fmic, 3” intake w/ k&n, and AP V3.
Largest turbo I would put on a stock block is a BNR S4 or GT/GTX3071. I would recommend instead something in the GT28 vicinity, eg GTX2867, GT/GTX2871, CS turbo or BNR S3. The stock block and fuel system will limit you to about 350 awhp on E85 or 300 awhp on 93. All of the GT28ish turbos will make the same power as the GT30ish bigger boys but spool 500-1000 RPM's earlier.
Some have had success DD'ing built motors. Personally I wouldn't. If your car is stock, I'd put some decent springs and shocks on the car, put some upgraded motor mounts in, and get a custom tune before anything else.
Pretty much. lol. OP has a lot of reading to do.
djohns
Greenie N00B Member
Hey now I’ll be using my car as a daily with a built motor don’t be hating lol.
therealleifmadse
Greenie N00B Member
Built after you ZZB with the S5?
djohns
Greenie N00B Member
No lol. I’m pre building before ZZB. I’ve got a spare motor. And I’ve only got the s4, if I had known the s5 was coming out I probably would have waited.Built after you ZZB with the S5?
Yeah I understand a stock motor wouldn’t hold up I was just wondering what the people who have it think about it. I agree fully im going to some more suspension work and mounts before even considering the BT. You think I could rebuild/ build my motor for maybe a 400-450awhp goal with 2k-3k? Jist the motor not everything else..
If you can find a machine shop with reasonable pricing, for sure you can build the motor for $3k. That's assuming you're willing to do all the labor yourself including some of the engine assembly. With that conservative a goal, you can reuse the stock head studs and leave the cylinder head stock. You'd just need pistons, rods, gaskets, bearings, some timing system components (I would especially recommend replacing the VVT actuator), all fluids, etc. All of that will run you about $2k. Heck you can probably reuse the main bearings if everything is in spec and you really want to get thrifty.
You will also need an upgraded clutch, put aside another $1000 for that.
Awesome thanks man. Yeah I have a friend who works in a local racing shop but he is used to V8 type stuff but internal work should be pretty familiar though. Is porting and polishing the head very much extra work/$$$ you think!? Also how big of a difference does a lightweight flywheel make?
[doublepost=1525143749][/doublepost]https://edgeautosport.com/stage-3-mzr-motor-build-kit-mazdaspeed-3-2007-2013-mazdaspeed-6-2006-2007/
This should be a good start to build off of right?
PnP'ing the head isn't worth it for your power goals. The flywheel makes a difference, but you also have to consider the mass of the entire rotating assembly including the pressure plate. Some are lighter than others. I think the ACT 6-puck with the street flywheel is probably your best bet.
The edge kit contains a lot of the components you'll need for the build, but honestly, I wouldn't buy that stuff from them. Their pricing is pretty steep and their shipping charges can be a bit much. You might be better off sourcing all of the parts individually.
What I think will end up happening if I don’t just spend the extra monry while I have it apart though is that I will want more power later. Haha It always seems to end up that way! So maybe best to do it all right the first time I guess idk... lol
therealleifmadse
Greenie N00B Member
Just working on an engine build and this is pretty much exactly what I experienced. Get everything apart, realize labour is "free" to just do the clutch now, so another $1000 into the pot. Then you figure add a turbo, but that requires a new intake system. And then you should do the downpipe and test pipe.
Next thing you know you're stripping the interior, doing an AC delete, ordering a new tri-mount kit from Damond, doing the balance shaft delete, getting an oil pan baffle, spin on conversion, prosport sandwich plate, PSS and oil intercoolers.........
But it was just going to be a stock+ build!
Between work and just personal driving I put between 500 and 1K miles a week on my built motor BT DD Speed 3. Almost 30K miles on it and not a peep (motor anyway. I did break the clutch pedal and had some fallout from that fiasco). Build it for what you expect out of it, and drive it. I don`t baby mine, but I don`t abuse it, either.
Haha Yeah sounds exactly like what is going to happen to me whenever I build mine. My turbo is hitting only like 15psi and the wastegate is getting up to over 50% right now so I don’t have high expectations for my stock setup right now.. lol I just don’t seem to ever have enough money to get it going! I don’t abuse mine either but I occasionally run it pretty hard but not up even into redline or anything like that. The stock K04 loses steam before redline almost anyways IMO.
AYOUSTIN
Greenie N00B Member
As said, leave the head as is, just make sure valve lash is in spec and that the valves are sealing on the seats properly. Don't bother porting it, you risk hurting your low end torque. Stock headbolts get iffy around 500ish whp but you'd be hard pressed to get further than that on a stock flange turbo.
Rods, pistons, gaskets, bearings (buy mains and rods, they're cheap), depending how many miles are on your engine I'd also consider a new oil pump. If your engine was made (or had the VVT TSB done on it) after 2012 then it should already have the updated actuator, if it doesn't add that to the list. Measure the chain to make sure it's not stretched, older versions had stretch issues. Beyond that everything is mostly reusable.
Have a machine shop check the cylinders for out or round, taper and size, if you were planning to do stock sized pistons, something to keep in mind is that most piston manufacturers size their stock bore pistons to be .003" - .0035" undersized so you'd need to measure your bores and then add .003" to see what your PWC would be. For your application I wouldn't run less than .0045", would probably shoot for .004". Obviously you can't close your bores up which is the downside to doing drop ins, you're kind of stuck with whatever PWC you get, unless it's too tight you can open it up, but that doesn't usually happen.
I wouldn't run a lightweight flywheel on a daily car. What lots of people don't realize is if you go too light it becomes a total cunt to drive smoothly. I've been in a couple of such cars and it's not fun having to rev the whore to 3k just to get moving. A single mass steel flywheel is perfect. If you're on a budget, stick to a factory flywheel. I thought there was someone out there making clutches that work with the factory flywheel.
Rods, pistons, gaskets, bearings (buy mains and rods, they're cheap), depending how many miles are on your engine I'd also consider a new oil pump. If your engine was made (or had the VVT TSB done on it) after 2012 then it should already have the updated actuator, if it doesn't add that to the list. Measure the chain to make sure it's not stretched, older versions had stretch issues. Beyond that everything is mostly reusable.
Have a machine shop check the cylinders for out or round, taper and size, if you were planning to do stock sized pistons, something to keep in mind is that most piston manufacturers size their stock bore pistons to be .003" - .0035" undersized so you'd need to measure your bores and then add .003" to see what your PWC would be. For your application I wouldn't run less than .0045", would probably shoot for .004". Obviously you can't close your bores up which is the downside to doing drop ins, you're kind of stuck with whatever PWC you get, unless it's too tight you can open it up, but that doesn't usually happen.
I wouldn't run a lightweight flywheel on a daily car. What lots of people don't realize is if you go too light it becomes a total cunt to drive smoothly. I've been in a couple of such cars and it's not fun having to rev the whore to 3k just to get moving. A single mass steel flywheel is perfect. If you're on a budget, stick to a factory flywheel. I thought there was someone out there making clutches that work with the factory flywheel.
Thanks for all the good info and im sure that they make them I haven’t looked at them too much yet. Is boring .002” over for 88mm worth the cost? I wasn’t for sure how much better it really is...?
