86' 325 es Track Build/Street Monster

[covertperformance]

So I accuired a new to me 86 325 es. Its a little rough around the edges but those make the best candidates for these kinds of builds. This is my first bmw so this is a whole new world to me. I currently fab a lot fo stuff for subarus,etc... i was originally going to do this with my sti, but couldnt make myself fully tear into a new and expensive car (to me). So this fit the bill perfectly.

The plan is to start with chassis work. Removing weight, chassis stiffening, rollcage, sheet metal dash, fuel tank, etc....

From there move on to exterior pieces hopefully lots of carbon bits to lighten things up. Want it low and able to mount big rubber.

Last but not least motor/turbo. Hopefully by the time i get to this 3rd step I'll finally have the funds for it. Going to have to do a lot of reading on the bmw motors/etc...to figure out the best setup.

Hopefully I can contribute back to the community as I'm sure theres a wealth of knowledge here to help me with my build.

Heres somes pics of some turbo stuff I do. I also make some chassis stiffening pieces, rollcages, and everythign in between. But everyone loves to look at turbo stuff :p-

321 stainless steel header

twinscroll manifold sch10 piping and cnc machined 304ss 1/2" flanges

Another turbo build using a gt30r with Tial V-Band Hotside

[e30nub]

Wow, amazing work. I think you've seen my buddies murdered out FXT around Roseville before. It's lowered with turbo back. He said he's seen your STi before.

[covertperformance]

My sti is usually torn down getting a bigger turbo, or for mock-up building someone a turbo setup. But Im almost done with all my prototyping of parts and jig building. So the sti will turn into the daily driver while my project gets attention.

Ive been doing tons of reading the past few days and still can decide on building the m20 or the m50. How much power can a built m20 (forged rods/pistons) handle? Id like to start scrounging for deals on blocks/heads and then order the other parts through my distributors so that by the time Im rdy to build the motor I have all my parts with as little money spent as possible

[Spaz]

Impressive looking welds/fabrication. I look forward to seeing what you'll do with the e30.

[e30esque]

Ive been doing tons of reading the past few days and still can decide on building the m20 or the m50. How much power can a built m20 (forged rods/pistons) handle? Id like to start scrounging for deals on blocks/heads and then order the other parts through my distributors so that by the time Im rdy to build the motor I have all my parts with as little money spent as possible

If you look at what PPF is doing in Scandinavia, they can build an m20 that will make upwards of 700. However, you are talking extensive headwork, rediculous cam, etc to do so. If you want to make a lot more streetable power at high levels, start with the iron block m50 or m52. They have been proven to make a ridiculous amount of power on a basically stock block.

[Ral]

depending on how much money you want to spend, look at the s50/s52's as well. They're the engines that came in e36 M3's. (95-99, if you're unfamiliar.)

If you look at what PPF is doing in Scandinavia, they can build an m20 that will make upwards of 700. However, you are talking extensive headwork, rediculous cam, etc to do so. If you want to make a lot more streetable power at high levels, start with the iron block m50 or m52. They have been proven to make a ridiculous amount of power on a basically stock block.

[covertperformance]

I know nothing about bmws, and their engines/trans and what works and what doesnt. Im trying to read as much info as possible. i'd like to run around 500whp or so on e85. So basically running a gt35r sized turbo is whats going to get me there. Will most likely run a twinscroll setup as well, for the best spool and transient response.

It looks like I could get that from the m20 with forged pistons, but it looks like the m50 does it safely. More robust block, the rods seem to be able to hold the power, but def need to upgrade to forged pistons instead of the cast pistons. The subys i deal with can hold up to some decent power but those cast pistons always seem to fail.

[rThor432]

depending on how much money you want to spend, look at the s50/s52's as well.

That's what I did to my 325eS. Great motor for the chassis. It would be perfect with snail power though..

[lennon]

Awesome work dude.

If choosing between the m20 and 24v for boost, I would choose the 24v motor over the m20 for sure. The m20 is great also, but if youre going for 500whp you might as well start with 24v. Im sure some will argue with that. Whether you choose m50, m52, s50, s52 is up to you/your budget. It doesnt seem like your budget is very tight, so youll probably want to start with the 3 or 3.2 liter motor. As you probably know, the only difference between all of those motors is displacement and camshafts. Castings are the same so you could make a 2.5 a 3.2 by transplanting parts. Several possible combos of OEM BMW cranks/rods/pistons. Not that you want to do just letting you know. You can get a set of custom wiseco or JE or other forged pistons for ~$1k or less in whatever compression and size etc you want.

There are tons of turbo 24v build threads on bimmerforums you should check out. Im definitely interested to see this project.

[covertperformance]

I'm def on a budget...the only reason I can do this is because I do all my own fab work. have my own tube bender for cage work and chassis work, etc..... I also have good vendors I've worked with for cnc flanges, sheetmetal laser/bending work.

The expensive part will come from the stuff I cant make, which will be the last things I do. because right now I dont much money, but metal is cheap and my time is free.

[RickSloan]

is you want 500hp on a low budget go m30b34 and a turbo end of story. You can make 400 on about stock internals and the m30 is no heavier then the m50x s5x motors and way way cheaper

[covertperformance]

If i put forged pistons in the m20 and did some head work and installed a cam. Realistically would I be alright? Id be happy with 400-500whp. I just want something thats not grenade in 5k miles.

I cant seem to find the limits on the m20 motor and its reliability with "big' hp builds.

[covertperformance]

I think I may keep things simple and just rebuild the m20 and put some forged goodies inside and do some head work. Id like to start producing parts for this setup. I'd like to build a full basic turbo setup and produce. Manifold and dump tube, full 3" tbe setup. Maybe even a intercooler setup as well. So its basically plug and play.

Run that setup for awhile and then swap in another motor and play with that for awhile.

[SamE30e]

M20's are proven to make 350hp with the 2.7i setup (325e bottom end 325i top end) But M50's and M30's can make more power for the same or less work.. Someone around me is making 350whp on pump gas in an M50 with ARP studs and a MLS gasket.

Looks like you do nice work though, good luck.

[covertperformance]

What kind of turbo is he running 30r?

I have so much to learn, seems like theres so many ways to swap parts between engines.