High compression pistons, need forged rods?

[MIKe30]

Invest in some euro headers if you can. The guy from bimmerworld said thart with head work and sunbelt race cams, they've seen between 8-14whp just from those. :nice:

And are you upgrading to the Dr. Vanos stage 2, and nice valve springs? I would.

Also you might as well get some bigger valves in there while your at it. :twisted:

You're too cheap to buy new cams and custom software, but want me to do all that? Easy to spend someone else's money isn't it? LOL.

I'm probably keeping stock exhuast manifolds to keep some sort of low end torque, and no - not likely doing the dr. vanos stage 2. I want this car done in the spring, not end of summer. Spending WAY too much on it as it, I need to buy some real estate - not waste money on e30's :(

Anyway, no on the valves as well. VAC stage 2 head with dual valve springs and upgraded retianers, full rebuild really, with 6 angle valve job should be PLENTY, imo.


btw, did you finish your cam job yet?

[2002maniac]

I'm probably keeping stock exhuast manifolds to keep some sort of low end torque

Sunbelts with stock manifolds? That will kill your top end power. Seriously.

If you are building a high flowing head you need good headers.

[nando]

good headers don't neccesarily mean you lose bottom end just like a properly chosen cam doesn't mean you lose your bottom end - torque will increase through the entire RPM range. Backpressure isn't good for anything, ever.

[MIKe30]

Sunbelts with stock manifolds? That will kill your top end power. Seriously.

If you are building a high flowing head you need good headers.

I thought so too, but that above dyno with the same cams and a built head had stock manifold.

good headers don't neccesarily mean you lose bottom end just like a properly chosen cam doesn't mean you lose your bottom end - torque will increase through the entire RPM range. Backpressure isn't good for anything, ever.

Please show me a before and after dyno of a header that increases torque throughout the entire rpm range.


I will probably fold before the motor goes in and end up getting euro headers.

[e30polak]

You're too cheap to buy new cams and custom software, but want me to do all that? Easy to spend someone else's money isn't it? LOL.

I'm probably keeping stock exhuast manifolds to keep some sort of low end torque, and no - not likely doing the dr. vanos stage 2. I want this car done in the spring, not end of summer. Spending WAY too much on it as it, I need to buy some real estate - not waste money on e30's :(

Anyway, no on the valves as well. VAC stage 2 head with dual valve springs and upgraded retianers, full rebuild really, with 6 angle valve job should be PLENTY, imo.


btw, did you finish your cam job yet?

I'm not too cheap, I'm too BROKE! Plus I'm gonna save to build the top end much like you, except with stock pistons. VAC is a rip off IMO. I have a local guy who builds sick motors for everything from chevy to porsche and I get shop cost.

I plan on +1mm intakes valves only, decking the head as much as I can while maintaining a factory head gasket, custom cams similar to sunbelts, a nice valve job, port matching the head, upgrading to dr. vanos stage 2 with new valve springs, and a lil 75 shot fogger kit...then have Osh at RMS dyno tune it. :pimp:

I will be doing the timing chain and water pump at the same time so I need to save up about 1500 to do it all since i will do most of the work myself. Hopefully I can do it all this summer! Right now I have to pay for classes so that I can enter a masters program in the fall.

P.S apparently re-timing the cam gears after the initial dyno and having it retuned has shown impressive results on the Sunbelts! That's what I plan to do for sure.

[mazur]

At the very least I would recommend the supersprint ebay knockoff's. They will definately outperform the stock crap.

Euro headers are the next best choice but mucho expensive.

[MIKe30]

Well, VAC may be slightly overpriced - but I have a reason I'd rather not disclose until later as to why I'd like to go to someone like them.

that spray should be a lot of fun...

I'm not too cheap, I'm too BROKE! Plus I'm gonna save to build the top end much like you, except with stock pistons. VAC is a rip off IMO. I have a local guy who builds sick motors for everything from chevy to porsche and I get shop cost.

I plan on +1mm intakes valves only, decking the head as much as I can while maintaining a factory head gasket, custom cams similar to sunbelts, a nice valve job, port matching the head, upgrading to dr. vanos stage 2 with new valve springs, and a lil 75 shot fogger kit...then have Osh at RMS dyno tune it. :pimp:

I will be doing the timing chain and water pump at the same time so I need to save up about 1500 to do it all since i will do most of the work myself. Hopefully I can do it all this summer! Right now I have to pay for classes so that I can enter a masters program in the fall.

P.S apparently re-timing the cam gears after the initial dyno and having it retuned has shown impressive results on the Sunbelts! That's what I plan to do for sure.

At the very least I would recommend the supersprint ebay knockoff's. They will definately outperform the stock crap.

Euro headers are the next best choice but mucho expensive.

Which do you think performs better, ebay or euros?



Think I've decided on 11.5:1. I've now got to decide which brand, and what size. Should I just assume the first oversize will clean up my scoring? Guess I should talk to the guy who machined my block the first time...

[e30s52]

Euros preform better but come at a higher cost.

[mazur]

+1 Euro headers will make more power. Just look at those secondaries! :)

Check this link out. Show real Euro Supersprint headers. The primaries look identical on the Ebay headers, but the secondaries are 2'' OD, like the Supersprints made for the US engines.

http://cgi.ebay.com/ebaymotors/BMW-E36-M3-SuperSprint-Stainless-Headers-325is-328is_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1229Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp3286Q2ec0Q2em14QQhashZitem180308256991QQitemZ180308256991QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Tough decision. But since you're worried about losing low end torque, I would probably go with Ebay.

[MIKe30]

Tough decision. But since you're worried about losing low end torque, I would probably go with Ebay.

Thanks for the heads up. To be honest i'm more worried about resolving this piston issue first though. I will look into it though.

[matt]

Wait... what is the piston issue? Buy wisecos... I can get them for you. Whatever compression ratio you want, and a couple different styles and options with coatings.

[SiGmA_X]

Just a couple comments.. I'd not go with the VAC head, I've read about issues with them from Evosport, and holy hell they are over priced. Have a good machinist do it for you locally, you'll save a ton of money and it well might be higher quality work. As for the pistons, TRM will source them for you for a VERY fair price. The issue I had (have) with the pistons from IPP are that the valve reliefs are MASSIVE. Way bigger than stock like I asked for. Bah.

[Widm3r]

SigmaX,

What do you have done to your motor to make 323whp... S/C or Turbo?


Goodluck on the build Mike, cant wait to see these numbers since this is a project i would like to tackle in the near future when funds permit...

PolakE30, What does a Dr. Vanos stage 2 kit do for increasing hp #'s?

[asubimmer]

Be aware you cannot spin the sunbelts as high as advertised without grenading the motor... LOTS of problems with club racers using them and popping motors. They may have the issues under control now but they were pretty bad at first...

With OBD2 you will be lucky to crack mid 260whp... You REALLY need to switch to OBD1 so you can get a TRM custom dyno tune. That alone will be good for probably 10-15hp over an off the shelf fash.

I am planning on building a solid lifter 3.0 alum block engine ( lighter) for mine this summer with CAT CAMS mechanical lifter cams, unless I can find another cam source for the mechanical lifter cams. Rev limit will depend on power peak.

If you have not bought pistons try to find a M52B28 alum engine. Use the S52 crank and custom pistons you end up with 3.0 and 30-40 lb lighter motor.... Thats my plan...

I hope you aren't building that alum block for anything other than driving to work. The alum block twists when puched hard, ie club racing like you mentioned. I hope you do a LOT more research before you blow all your $$$.

[MIKe30]

Wait... what is the piston issue? Buy wisecos... I can get them for you. Whatever compression ratio you want, and a couple different styles and options with coatings.

PM is about to be sent :)

Goodluck on the build Mike, cant wait to see these numbers since this is a project i would like to tackle in the near future when funds permit...

Thanks. I can't wait to get it done. Today was a gorgeous day out. Come springtime, days like today will kill me until the car is done..