how much hp will stock pistons hold up

[Aktiv3]

ive got a 99 328i and im doing stg3 head with fi cams,either 330 crank or m3 crank..not sure..eagle rods,aa stg 2 c38 with prototype pulley for 15 psi. aa meth ,aa headers exhaust,no ctas,dinan throttle body,obd1 manifold,cry02 intercoolersprayer.....so what my question is...is will stock 330 zhp pistons hold up that much hp/trq for what im wanting to do and not have a problm or would i need to go ahead and do pistons...thanks

[malina]

FYI, the first thing to fail going over 17:1 effective compression will be the head gasket. After that, I'm betting it would be a rod at some sick power level. BMW pistons are pretty impressive from the factory. (I believe they are manufactured by Mahle, they even come with coated skirts to reduce friction) The main reason to change pistons in my mind is CR...unless you are running nitrous. Then you want to focus on crown shape and the alloy.
With stock e46 330 pistons @ 15 PSI of boost, Effective Compression Ratio will be over 20:1. Why not to switch to lower compression ratio pistons?

[MSpired]

The Rotrex c38 blower will not make 15psi, and if you push it hard enough to make that, the IAT's are most likely going to be SUPER hot! (that's if the supercharger doesn't fail before that)

[BimmerDude18]

The Rotrex c38 blower will not make 15psi, and if you push it hard enough to make that, the IAT's are most likely going to be SUPER hot! (that's if the supercharger doesn't fail before that)I'd question that, its making 13+ on David's car without issue.

[bernstem]

With stock e46 330 pistons @ 15 PSI of boost, Effective Compression Ratio will be over 20:1. Why not to switch to lower compression ratio pistons?

I'll second that. If you are replacing the crank anyways, why not go low compression forged pistons, forged rods and balanced crankshaft? You already spent the money to take the engine apart, the cost of better internals is minor.

[pei330ci]

ive got a 99 328i and im doing stg3 head with fi cams,either 330 crank or m3 crank..not sure..eagle rods,aa stg 2 c38 with prototype pulley for 15 psi. aa meth ,aa headers exhaust,no ctas,dinan throttle body,obd1 manifold,cry02 intercoolersprayer.....so what my question is...is will stock 330 zhp pistons hold up that much hp/trq for what im wanting to do and not have a problm or would i need to go ahead and do pistons...thanks

That's a $30k project. Why the heck are you even considering using stock pistons?!?!

Please clarify which M3 crank you are refering to?

[MSpired]

Maybe he means M3 crank pulley?

I'd question that, its making 13+ on David's car without issue.

Crazy :excited:

[malina]

I'd question that, its making 13+ on David's car without issue.

And that (13 PSI) may be the limit of C38 efficiency on a stock M54B28 engine. I assume it's going to be less PSI for M54B30.

[BimmerDude18]

And that (13 PSI) may be the limit of C38 efficiency on a stock M54B28 engine. I assume it's going to be less PSI for M54B30.
You don't know that though, merely speculating. My buddy is upping the boost on his S54 from 9 psi to I believe 10.5, so don't "state" the limits without at least knowing them.

[zeshon]

You don't know that though, merely speculating. My buddy is upping the boost on his S54 from 9 psi to I believe 10.5, so don't "state" the limits without at least knowing them.

M3 trim blower is 81 trim, non is 71 I believe.

Also, to the OP, Dinan doesn't do a throttle body for the M52TU, and I'm curious as to why you would want to spend all of this money on an older gen 328 when you can probably sell your car and buy a new one in cash based on what you plan to spend. Sentimental value is only worth so much, and the scope of this project is huge.

If you decide you really need to drop 20-30k on your 8 year old car, then while your shopping VAC's site (I'm assuming that's where you saw the "STAGE 3" head and eagle rods), you need to order yourself a set of forged pistons. Also, since your wallet seems to be deep as hell, you will need an LSD, and turner reinforcements to make your car not worthless with all of that power. Also, you're gonna want good tires, and your suspension bushings will all probably need to be refreshed.

All in all, you're talking about a totally new car. If you decide you really need that, then post progress pictures along the way.

[BimmerDude18]

M3 trim blower is 81 trim, non is 71 I believe.

Also, to the OP, Dinan doesn't do a throttle body for the M52TU, and I'm curious as to why you would want to spend all of this money on an older gen 328 when you can probably sell your car and buy a new one in cash based on what you plan to spend. Sentimental value is only worth so much, and the scope of this project is huge.

If you decide you really need to drop 20-30k on your 8 year old car, then while your shopping VAC's site (I'm assuming that's where you saw the "STAGE 3" head and eagle rods), you need to order yourself a set of forged pistons. Also, since your wallet seems to be deep as hell, you will need an LSD, and turner reinforcements to make your car not worthless with all of that power. Also, you're gonna want good tires, and your suspension bushings will all probably need to be refreshed.

All in all, you're talking about a totally new car. If you decide you really need that, then post progress pictures along the way.Yup, but with all the other money being spent...might as well LOL.

I just don't like to make assumptions. AA would be my source of information on that (or rotrex) since they will likely be responsible for coming up with a fuel/spark map.

[AntB]

It's same reason as the people who put 20k into a 1k car... because they can! I support your decision, make it a beast, and def upgrade the pistons if you're already in there man.

[zeshon]

It's same reason as the people who put 20k into a 1k car... because they can! I support your decision, make it a beast, and def upgrade the pistons if you're already in there man.

Doesn't mean it's a good decision.

Lets play the cost game
AA stage 2 C38 + magic upgrade pulley = 6k + or -
"Stage 3" Head work = 2k
FI cams = 1k
330 crank = 500ish (not sure on this one)
Rods = 2k
Pistons = 1k
Exhaust = 1.5ksih
OBD1 manifold, custom adapter plate, making it all work = 2-3k (I think it's even more than this, not sure)
Cryo intercooler spray = 1-2k
Professional rebuild and blueprinting = 8-12k
LSD = 4k
Suspension, including bushings = 3-5k
New wheels and rubber = 3-5k

Somewhere between 30-40k. Lets say you sold your 328 for 8k, you're at almost 50k.

Lets say you now bought a M3, 25-35k. You can now afford a stage 1 or 2 HPF kit, you're making much more power than you would have out of the M52TU, it's more reliable, better looking, and will be better on gas mileage (most likely).

All in all, there is no reason to do this kind of a build unless you have stupid money. That is all.

[Activ3]

I've maxed the rotrex blower @ 14.8psi on the M52TUB28 with an otherwise stock motor except for headers.

The B30 with stock intake manifold and aftermarket headers will be around 13psi with a C38-71 and 80mm pulley. The 81 trim might get you up to 14psi on a stock motor with aftermarket headers.

Honestly, I'd say if you're car is stock now, and you've never driven a relatively quick car, just get the standard bolt on C38 stg2 kit. I'd imagine that with that kit and headers, you'd be quite happy for the time being. As you progressively mod your car, you're going to run in to more problems that you may really not want to deal with. Adding up parts for a build is one thing, but many people don't take in to consideration all the little things that you'll need along the way.

[mcr_driver]

+1 on the parts adding up considering the cash you have now *assuming* why not get a used E46m3 enjoy that then add some F/I later on as you beef up your experience with the car (track time)

[nleksan]

I can understand his reason for wanting to boost the car he has now. There is certainly a sentimental value to it, and that, for some people, can trump "better bang for your buck". I, for one, plan on ESS Stage3 Twin-Screw'ing my 328Ci. I love the car to death, and plan on keeping it forever. I never foresee myself selling the car, and while it may go from daily driver to weekend/show/track car, I'd do just about anything else before I'd sell my car (assuming I HAD to have the money). I've had it for 3 years almost, and I know it inside-and-out; I know all of the service that's been done to it, I know that it's all been done by excellent technicians, I've put thousands of dollars into suspension and brake upgrades, the engine is solid as could possibly be, it is a "strong" M52TU (dyno shows me making around 208hp at the crank, with only possible "power-enhancing mods" being a custom-mad CAI and Rogue Engineering "Race" Tranny Mounts), it's the exact color combo I want (Topaz over Dove Grey Leather), it's fully-loaded, and the subframe issue was taken car of by BMW outside of the warranty (it cracked at 74.9k miles; BMW paid for the fix, and it now looks like it's much stronger).

Plus, the M52TU is a great engine for modifying, IMO. It has a "true" throttle, it has nice thick cylinder walls, very even HP/TQ numbers and a good power curve, excellent stock gearbox (although 6-speed swap is on the way), and in the E36-world the M52 makes AMAZING numbers when strapped with a turbo kit (custom). I think an ESS TSE3 (14psi, cams, pistons, rods, crank), "Stage 3" Head (valves, valve-springs, etc), Intercooler, Oil Cooler, aFe intake, custom under-drive/lightweight pulleys, Headers (jet-hot coated), Random Technology cats, custom M3-style quad (switching from 323/328 style "single" exhaust to 325/330 style "true dual", and running it back into an M3 rear muffler), Stage 3 Clutch, 10lb flywheel, 3.07 LSD, 6-speed transmission swap, custom-flared fenders to fit 19x9F 19x11R (style-TBD) lightweight wheels with 245F and 285R tires, StopTech 6-Piston Front and 4-Piston Rear BBK, Carbon-Fiber for weigh reduction (M-Tech II Splitters, Vorsteiner GTR Hood, M3 CSL Trunk, GTR Sideskirts, CSL-style rear diffuser, and possibly the CF Roof), weight reduction via Sparco/Recaro seats, UUC EvoIII SSK w/ DSSR, TMS Subframe Kit, Solid Differential Bushings, RE "Race" Engine Mounts, M3 steering wheel, removal of rear seat and installation of custom CF rear "bench", custom CF door-panels, Hotchkis H-Sport Sways, UUC Chromoly Adj. Rear Control Arms, F/R Strut bars, BSW S1 sound system, custom "X-brace"-style reinforcement/chassis-stiffener, carbon-fiber M3 Mirrors, CF center-console, and a bit more. Sounds like "big plans" that "I'll never be able to finish"? Think again... Determination (and a steady income w/ no dependants) can make anything happen...
I don't expect it to happen overnight, but rather, over the next 3 years or so. Prices will start to drop for E46 parts (not a whole lot, but some) as E90/92's take over the scene. $40,000 in work spread out over 3ish years is completely feasible, even if the person wasn't making a whole lot of money. I'm not rich, but I pull in enough to make this feasible while I still live quite comfortably. Is it the most financially-sound thing to do? No. Is any hobby? No. But when I look at my mod-list in Excel, and it is over a full page long (probably close to two), and then go look at my car, and take it for a drive, I'll know that it's worth it because it has yet to fail to put a smile on my face... Having it modified to-the-gills will only increase that.
That, and as I said before, once the tranny swap, TSE3 and associated engine internals, "stage3" Head, and custom WBK are installed, it will cease to be a daily-driver. I'm waiting off on the TSE3 because the dollar is so weak, and it's a European company... Fiscally irresponsible in this regard doesn't make me dumb with my money.
Also, labor won't be much of an issue at all. I have personal friends that own: a well-regarded local body shop, a BMW dealer/tuner shop that specializes in modifying cars like this, and a friend who does custom-carbon-fiber work. I will pay $0.50 on the dollar, if that, in terms of labor for ANYTHING: paint, fitting, custom-body-work, supercharger-install, engine rebuild, tranny swap, custom-carbon-fiber rear-bench, etc. Some of it will come free. So parts are the big cost-concern, not installing them (which is an area many people overlook; I'm just lucky).

If I had to start from scratch, yeah, I'd buy a late-model M3 Competition Package and build off of that, but I currently see no reason to. With the aforementioned modifications, my car should make 400rwhp+, weight at least -350lbs, lose 20lbs+ in unsprung weight, and reduce drive-train inefficiency from around 15% down to 10-11%. High goals, but reachable. I could do a whole string of mods right now, but I prefer to save up my money in my "mod"-fund, and just do a section at a time (even though my labor costs are cheap, they still cost money, so I'd like to save that money and get all the body work done at once, etc).

Call me dumb, call me whatever. But I love my car, and she hasn't let me down, so I'm not going to let her down.

[SILVER_BIMMER]

WOW - NICE WORDS GREAT GREAT THANKS FOR nleksan - I have an 328ci 2000 automatic and i was wondering to sell or not to sell. some mods some changes but the car stills strong. Nice and well mantained here in Puerto Rico. weathers is to hot.. sometimes rains to much ..but when the car starts to ask for replacement mantainance parts I do what ever i takes to do it fast. !! Example yesterday strange sound in front fan.. I pull over call my friend -SAYS Waterpump..towing service.. some beers. some rum bottles fix car during the afternoon and today driving like new ....It is the best of the best...

[pei330ci]

I can understand his reason for wanting to boost the car he has now. There is certainly a sentimental value to it, and that, for some people, can trump "better bang for your buck". I, for one, plan on ESS Stage3 Twin-Screw'ing my 328Ci. I love the car to death, and plan on keeping it forever. I never foresee myself selling the car, and while it may go from daily driver to weekend/show/track car, I'd do just about anything else before I'd sell my car (assuming I HAD to have the money). I've had it for 3 years almost, and I know it inside-and-out; I know all of the service that's been done to it, I know that it's all been done by excellent technicians, I've put thousands of dollars into suspension and brake upgrades, the engine is solid as could possibly be, it is a "strong" M52TU (dyno shows me making around 208hp at the crank, with only possible "power-enhancing mods" being a custom-mad CAI and Rogue Engineering "Race" Tranny Mounts), it's the exact color combo I want (Topaz over Dove Grey Leather), it's fully-loaded, and the subframe issue was taken car of by BMW outside of the warranty (it cracked at 74.9k miles; BMW paid for the fix, and it now looks like it's much stronger).

Plus, the M52TU is a great engine for modifying, IMO. It has a "true" throttle, it has nice thick cylinder walls, very even HP/TQ numbers and a good power curve, excellent stock gearbox (although 6-speed swap is on the way), and in the E36-world the M52 makes AMAZING numbers when strapped with a turbo kit (custom). I think an ESS TSE3 (14psi, cams, pistons, rods, crank), "Stage 3" Head (valves, valve-springs, etc), Intercooler, Oil Cooler, aFe intake, custom under-drive/lightweight pulleys, Headers (jet-hot coated), Random Technology cats, custom M3-style quad (switching from 323/328 style "single" exhaust to 325/330 style "true dual", and running it back into an M3 rear muffler), Stage 3 Clutch, 10lb flywheel, 3.07 LSD, 6-speed transmission swap, custom-flared fenders to fit 19x9F 19x11R (style-TBD) lightweight wheels with 245F and 285R tires, StopTech 6-Piston Front and 4-Piston Rear BBK, Carbon-Fiber for weigh reduction (M-Tech II Splitters, Vorsteiner GTR Hood, M3 CSL Trunk, GTR Sideskirts, CSL-style rear diffuser, and possibly the CF Roof), weight reduction via Sparco/Recaro seats, UUC EvoIII SSK w/ DSSR, TMS Subframe Kit, Solid Differential Bushings, RE "Race" Engine Mounts, M3 steering wheel, removal of rear seat and installation of custom CF rear "bench", custom CF door-panels, Hotchkis H-Sport Sways, UUC Chromoly Adj. Rear Control Arms, F/R Strut bars, BSW S1 sound system, custom "X-brace"-style reinforcement/chassis-stiffener, carbon-fiber M3 Mirrors, CF center-console, and a bit more. Sounds like "big plans" that "I'll never be able to finish"? Think again... Determination (and a steady income w/ no dependants) can make anything happen...
I don't expect it to happen overnight, but rather, over the next 3 years or so. Prices will start to drop for E46 parts (not a whole lot, but some) as E90/92's take over the scene. $40,000 in work spread out over 3ish years is completely feasible, even if the person wasn't making a whole lot of money. I'm not rich, but I pull in enough to make this feasible while I still live quite comfortably. Is it the most financially-sound thing to do? No. Is any hobby? No. But when I look at my mod-list in Excel, and it is over a full page long (probably close to two), and then go look at my car, and take it for a drive, I'll know that it's worth it because it has yet to fail to put a smile on my face... Having it modified to-the-gills will only increase that.
That, and as I said before, once the tranny swap, TSE3 and associated engine internals, "stage3" Head, and custom WBK are installed, it will cease to be a daily-driver. I'm waiting off on the TSE3 because the dollar is so weak, and it's a European company... Fiscally irresponsible in this regard doesn't make me dumb with my money.
Also, labor won't be much of an issue at all. I have personal friends that own: a well-regarded local body shop, a BMW dealer/tuner shop that specializes in modifying cars like this, and a friend who does custom-carbon-fiber work. I will pay $0.50 on the dollar, if that, in terms of labor for ANYTHING: paint, fitting, custom-body-work, supercharger-install, engine rebuild, tranny swap, custom-carbon-fiber rear-bench, etc. Some of it will come free. So parts are the big cost-concern, not installing them (which is an area many people overlook; I'm just lucky).

If I had to start from scratch, yeah, I'd buy a late-model M3 Competition Package and build off of that, but I currently see no reason to. With the aforementioned modifications, my car should make 400rwhp+, weight at least -350lbs, lose 20lbs+ in unsprung weight, and reduce drive-train inefficiency from around 15% down to 10-11%. High goals, but reachable. I could do a whole string of mods right now, but I prefer to save up my money in my "mod"-fund, and just do a section at a time (even though my labor costs are cheap, they still cost money, so I'd like to save that money and get all the body work done at once, etc).

Call me dumb, call me whatever. But I love my car, and she hasn't let me down, so I'm not going to let her down.

I do 90% of the work on my car. It still costs more than I ever thought...

Anything is possible though if you are 100% commited to your goals, and "see" them as being possible in even the most dire of circumstances.

[krenar]

if i could have that cash ill drop them for the new m3 and pay the rest monthly