Who is running a potent N/A set up?

[oxymoron]

let me know all about your na builds, i just got my first e30 and i am of course looking for more power already so tell me about the stuff your running, exhaust, chips, cams ? and if you have numbers?
i have an 88 325is so it/d be the b25 of course

[Chaz]

Sup g, im running that stock motor in it. But i got it lowered like 4 inches with 17's on that bish. its also got a huge spoiler and dope body kit. i bet with all that its got like 300whp. lemme no if u want any more tips dawgg

[bmwguy325is]

Well N/A means $$$. There are some awsome N/A builds out there.
What are you willing to spend?
The best way to make a noticeable difference is MAF kit conversion. There are a few out there I run the miller conversion with their WAR chip.
Also long tube headers are the only way to go. and then a single 2.5 exhaust.

[Sagaris]

Everyone will steer you a different direction. It is incredibly difficult to wade through all the crap and pick out solid information which will get your car running how you want it to. There are many different formulas for success, but you define what success is. For me, success is having a reliable engine which is perfectly tuned, has crisp response, awesome induction noise, which provides adequate thrust to keep me smiling. There is always a bigger badder twin engined stroker nitrous Veyron around the corner that can beat you in a drag race so try not to get caught up in just trying to go fast in a straight line because cars and driving should be so much more than an acceleration contest. If that matters a lot to you then I might suggest exiting the building now before proceeding further and finding something with forced induction or no less than 4.5 liters of displacement

1.) Don't expect to build an STi killer out of an old-tech 12 valve N/A 2.5L without the knowledge, or budget, of an F1 engineering team.

2.) Don't attempt to extract additional power out of the car without bringing it back to an original state of tune, this means spending a lot of money on fresh sensors, wires, timing belt, valve adjustment, making sure the car is running at full operating temperature and so forth. If more people had healthy M20's when they decided to swap for an M50/M52, they likely wouldn't have decided to swap.

3.) Don't forget that the performance of your car is equal to the sum of its parts. Wheel size and weight matters, vehicle weight matters, drivetrain losses matter (bearings, lubrication) etc..

With that said, here is my setup:

My list of "of the shelf mods" is simply a chip, 17.5# injectors, an intake setup. A handful of other things have been done to it which are small things that add up and in the grande scheme of being favorable in the eyes of the forum gods I will refrain from speaking of such things. As an automatic (currently undergoing 5spd swap) it was quite a bit faster than my 5spd 325i with 4.10 diff and rebuilt engine and has provoked such comments from passengers such as:

"This thing is only a 2.5?!?!?" -Dad
"That was not at all what I had expected" -LS1 Camaro owner
"F*** life!" -Driver of a K20 Civic Si who was stoked about his new hondata tune, intake, and exhaust setup until learning what the rear of an E30 looks like.

Megasquirt coming soon. Even after 2 years, I still have yet to figure out exactly how I want to build the bottom end of the engine. Many more calculations must be performed before I feel good about making a solid decision.


My point here is to focus on having a healthy M20 first, then when its time for upgrades, be skeptical, do tons of your own research, and try to get unbiased opinions. Don't forget that everything surrounding the engine is just as important for performance as the engine itself.

[Mr Two]

To be fair, the motor in an EP3 SI is hardly worthy of the K20 designation. They made 160bhp stock, less than an M20. It's a fuel econ motor.

[Sagaris]

True, but considering it had about 160,000 fewer miles than my engine, similar weight and was a manual trans (mine was still auto), one would not immediately place odds on my side of the table.

[Fernflex]

My car is @ 175whp with out tune with stock afm and rev limiter is 6,900 rpm. Yesterday I received the megasquirt and the last set I needed to install a home made itbs kit.

I can still give a more aggressive head job, more compression, bigger piston, 304 cam, heavy duty rocker arm, bigger injectors, better headers.

I totally agree with Sagaris the M20 has potential but it also limited unless your budget is huge. Doing an engine swap has benefits but also all parts are more expensive. The benefit of E30 m20 power to weight ratio helps you a lot.

[nando]

how much power do you want and how much money do you have? 200-220bhp is fairly easy and "cheap" to get to. beyond that, it gets really expensive.

[SpecM]

200-220bhp is fairly easy and "cheap" to get to.

any details or tips on this? I'm planning to build a street 2.8 (m52 crank) with a 272 cam soon... or should I go another way?

looking for 'best bang for buck'

[nando]

well when I say "cheap" I mean you still need a good $3-5k budget. It needs to be tuned, you don't want to use bargain-basement parts (used stock cranks and rods are fine), it needs good exhaust, etc.

best way to do it without overspending is to do a lot of research and planning. do it right the first time, or don't bother.

if you want power - all cams cost about the same. while you don't want to go *too* agressive on a street car, IMO something like a 272 is pretty well a waste of money. you could do a 284/272 or 288 for the same price and have more power potential from the head for about the same cost.

same with the bottom end - a 2.8 with custom pistons costs about the same as a 3.2. the price difference between my 2.8 with 86mm MM pistons and a 3.2 with the same pistons was only about $300. I should have built the 3.2 to begin with, but now I'm looking at starting over from scratch because I can't go any further with the 2.8.

[oxymoron]

well before this post i had the idea that doing a few motor mods would be a lot cheaper then going with aturbo set up, but if it is going to be the same price to get 220hp as it would be to get 300 wit ha turbo, i dont know how interested i am in an na build. thoughts?

[nando]

well, the N/A engine will be simpler and more reliable in the long run. Turbos definitely make more power but it's more difficult to set up properly, the engine has to be built stronger, the tune is even more important, and maintenance is going to be more work.

there are also big differences in power delivery. I prefer N/A. If you only drive it once in a while though, turbo can make sense.

[Wanganstyle]

well before this post i had the idea that doing a few motor mods would be a lot cheaper then going with aturbo set up, but if it is going to be the same price to get 220hp as it would be to get 300 wit ha turbo, i dont know how interested i am in an na build. thoughts?

both are expensive!

if you care about budget and want xyz power (220hp NA):

220hp NA is easiest done by installing a M30b35. It should be there with 230 torque + de-catted, chip mapped. dont even need to open the motor if its a known good working one. the one in my prior e32 735i was already attached to a G260 and would have fit right in.

re-configuring the internals of these I6's are not really any less than rebuilding an expensive modern powerplant.

a worked out all out NA high power crazy m20 could get into the S54B32 stock engine build up SPENDING range pretty easily.

to get a M20 NA into S54 power range....you'd need a deep TEAM BUDGET.

[digger]

a worked out all out NA high power crazy m20 could get into the S54B32 stock engine range pretty easily.

Lol

[acolella76]

both are expensive!

if you care about budget and want xyz power (220hp NA):

220hp NA is easiest done by installing a M30b35. It should be there with 230 torque + de-catted, chip mapped. dont even need to open the motor if its a known good working one. the one in my prior e32 735i was already attached to a G260 and would have fit right in.

re-configuring the internals of these I6's are not really any less than rebuilding an expensive modern powerplant.

a worked out all out NA high power crazy m20 could get into the S54B32 stock engine range pretty easily.

uh.. that's almost a 200hp increase in power.