M3 stock engine capacity

[50trimtsi]

hi guys. I just joined the forums. I have been reading through lots of threads lately, but havnt been able to find the right answers. I may have simply overlooked it and am sorry if this is the case, but ill ask anyway. Basically my friend just bought a 95 M3 and i instantly became addicted. So now im planning on getting one too. I like to do a lot of research before i go and spend that kind of money. I have found lots of helpful info but need the real basics. Im looking at getting a 95 or 96-99. Can anyone tell me the major differences between these cars and do either have a better modification base. Also my other major and hopefully fairly simple question, how much horsepower can one of these cars handle on a totally stock engine? not sure which type of FI system im gonna go with yet. I have found many threads on that luckily. Id base my choice on my needs and what a stock engine can handle as a daily driver for a long time. I dont want it to handle the HP for a year and than blow up either. Hopefully this is descriptive enough for a good estimation based on everyones experiences. Thanks alot. Matt

[dieselnuts]

the 95 has the obd1 diagnostics where the 96-99 has the obd2. the 95 responds to modifications a lot better than the later years. I dont have an m3....yet..... but near the end of this year, i hope to be purchasing one. because of the above statement, I will be getting a 95. About the HP question, I am curious about that myself. hope this helps.

[50trimtsi]

if 95's respond better to mods, then thats what I will probably shoot for. Thanks man and I hope somebody can help us out on the stock engine capacity and also the tranny, although ive heard they can hold a lot of power, but i could be wrong there. Thanks.

[bmxcm]

i've seen many people go in upwards of 400 rwhp even 500 on stock internals and tranny(clutch is an obvious needed upgrade)...also if u have the cash i would think that going w/a 97-99(3.2L) w/OBD1 conversion would be the best route for power.

[dieselnuts]

Originally Posted by bmxcm

i've seen many people go in upwards of 400 rwhp even 500 on stock internals and tranny(clutch is an obvious needed upgrade)...also if u have the cash i would think that going w/a 97-99(3.2L) w/OBD1 conversion would be the best route for power.

Ive heard that you have a lot of electrical problems with this conversion. Once again this is hearsay, but usually these types of conversions do have their problems.

[CarlsbadCroak]

Electronically, there are no problems with an OBD2 conversion, it's a plug-in swap of the OBD1 harness and computer, no hacking or cutting or splicing or soldering. You've got to adapt a few mechanical bits to make it work though nothing major there either.

The 95 had a 3.0 engine rated at 240hp and 225 ft/lbs torque that was better breathing in the upper RPM range, cast iron exhaust manifolds, rotorary dialed climate control, 17x7.5 inch wheels and 235/40/17 tires, a 3.15 limited slip rear differential, a quicker ratio steering rack, and better suspension geometry (better meaning more neutral handling). The 3.0 was easy to mod, responding well to intake and exhaust changes, and the tuning was made easy because you could just swap a chip.

The '96 added electronic climate controls, less aggressive suspension geometry along with staggered 17x7.5 front 17x8.5 rear (225/45/17 front, 245/40/17 rear), and the steering rack was the same found in all the other 3 series cars (less aggressive). It was the first year of the OBD2 3.2 engine, which made the same 240 HP as the old 3.0 engine, but 236 ft/lbs of torque, that ran out of breath past 6k RPM due to a more restrictive intake manifold, but was better suited for crusing around town thanks to higher low-end torque. Same basic transmission, but now with a 3.23 limited slip (with the increased rear tire size, it's about the same gearing as the 3.15). Along with the OBD2 electronics came revised exhaust manifolds in stainless steel, a different catalyst section, and a slightly different exhaust (internally). And it uses FOUR oxygen sensors instead of 1 on the OBD1 cars. From the outside, you'd have a hard time telling the '95 and '96 apart, except for wheels.

97-99 are mechanically the same as the '96, but there were a few incremental upgrades. In 97 the nose panel was changed slightly, with wider kidney grills, and the side marker blinkers were made smaller. Door airbags were introduced in '98, along with a new three spoke steering wheel. You could also buy a 4 door in '97 and '98.

The tuning/performance problems with the OBD2 cars can be gotten around, the most common is to swap the intake manifolds for an easy to find and cheap OBD1 manifold to gain some of the rev-happy nature and higher RPM HP of the 3.0, while still using the OBD2 electronics, and there are several companies that have figured out the OBD2 computer, so it's ALMOST as easy to upgrade as an OBD1 in terms of software.

The OBD2 engine has more POTENTIAL for HP due to more displacement, and always makes more torque. As far as the suspenion geometry, if you're really concerned about handling you can retrofit all the '95 parts.

The downside is emissions regulations. It's easier to get around or pass inspections with the OBD1 car, and it's ILLEGAL to convert an OBD2 car to OBD1. For some that's no big deal, and for others, it's more of a concern.

[nondescript]

Don't forget about the rear swaybar change for 99...

[50trimtsi]

First off I would just like to thank you guys for being soo helpful on this subject. I got the exact answers i was looking for as well as very decriptive detailed responces. I really appreciate that. Overall and economically it looks like the 95 M3 might be the best bet for me. Throw a nice free flowing exhaust,and one of the supercharger kits ive been seeing for 6grand that should get me 350 and 290 at the wheels. Personally that sounds pretty quick and nothing to look down on. No it isnt like a lot of guys on here, but seems respectable to me. Plus it sounds like that would still be reliable on the car as a daily driver and shouldnt kill my engine or drivetrain, minus clutch. Does this sound about right to you guys or am i not thinking correctly on the subject? Thanks again for all the help. I really do appreciate it a lot.

[CarlsbadCroak]

I ran the base Dinan kit on my 3.0 for about 3 months and the car was plenty quick, I was able to do low 13's in the 1/4 on street tires and crappy 60 foot times. But power is addictive so I increased boost, added aftercooler, larger injectors, etc. See my sig for details on my current power level.

That said, the car is my daily driver (it's my ONLY driver at the moment), and has been very reliable, no boost related issues at all, unless you count the clutch. I've ran it 20k miles, and ran it hard, with the supercharger and she's still taking it.

I just replaced the clutch last week, the old OEM one had 24k miles on it, almost all of that under boost, and it wasn't shot or even slipping, but it didn't have long left. I can't blame that totally on the SC, I have a lead foot, a lightweight flywheel, 3.38 rear diff, sticky tires, and slip the clutch a lot in daily stop and go driving, not to mention the fact that the car spent some time on the dragstrip and more than a few 4k RPM launches on the street as well. 2 years/24k miles is not bad if you take all that into account, and I went ahead and put another OEM clutch back in this time rather than a more expensive performance clutch.

[BeeEmDubAU]

I've heard that they've pretty much gotten around the OBD1 vs. OBD2 issues, and that there is no real difference in how they respond to mods now. Is this true, or is it just misinformation?

[CarlsbadCroak]

It's still a bit more expensive to mod an OBD2 in some cases.

[bmxcm]

i have the conversion on my car and the only issue i have is w/emissions!! its done b/c of the ability to get more hp out of mods and i've heard its easier to tweak...maybe different now. also obd2 has the adaptive mapping or whatever its called so if u dont romp on it often you get inconsistant performance.

[50trimtsi]

guys thanks so much for your help on this subject. Really nice to know you guys are this helpful to a newbie on his first thread. Thanks again for all the help. It will difinately be taken into acount in picking and modding my m3.!! Ill be selling my TSI this week!!

[///3oris]

Originally Posted by 50trimtsi

hi guys. I just joined the forums. I have been reading through lots of threads lately, but havnt been able to find the right answers. I may have simply overlooked it and am sorry if this is the case, but ill ask anyway. Basically my friend just bought a 95 M3 and i instantly became addicted. So now im planning on getting one too. I like to do a lot of research before i go and spend that kind of money. I have found lots of helpful info but need the real basics. Im looking at getting a 95 or 96-99. Can anyone tell me the major differences between these cars and do either have a better modification base. Also my other major and hopefully fairly simple question, how much horsepower can one of these cars handle on a totally stock engine? not sure which type of FI system im gonna go with yet. I have found many threads on that luckily. Id base my choice on my needs and what a stock engine can handle as a daily driver for a long time. I dont want it to handle the HP for a year and than blow up either. Hopefully this is descriptive enough for a good estimation based on everyones experiences. Thanks alot. Matt

If you can afford it get the latest year M3. If I could do it all over again, I'd get the '99. There are tons of little bodily and mechanic updates that are very nice. The 3.2 can also support more power. Even in stock form you can add the OBD-I manifold to the 3.2 and gain some good power.

OBD-II also gives you very useful information via an OBD-II scanner if you decide to go FI (so you're not blind)

My vote is definitely for the latest possible...

Boris