318 vs. 325

[ten2doyle102]

ok so i have 2 e30s that i would like to turn on into a auto cross car. Now i am sure that this has already been asked but i was wondering which one everyone thought would be a better choice for autocross.

Currently my 318 is in pretty good condition body wise but the engine power obviously just doesnt compare. I know that engine power doesnt mean anything when it comes to racing so that's why i was leaning towards the 318 since its a better balanced car. the only thing that i would really have to do would be to rebuild the motor cause its got 234,000 miles on it and a refresher may be in order. oh and it only has a 4.10 open diff too.

my 325, however, would pretty much be a complete redo. the motor ticks, the suspension is toast, and the exhaust is totally rotted out. Its got plenty of power however, much more than my 318.

i dont know, the 318 would be easier but the 325 might be more fun. this will be my first autocrosser so i am new to the scene. I have some suspension part that i have coming, they are as follows

Bilstein HD's all around
Eibach Pro kit Springs
Suspension Techiques sways
Stronger shock mounts
Carr Industies F & R strut bars

let me know what else i should possibly think about doing to the car

Thanks!!!

Matt

[kishg]

go with 325.

[ten2doyle102]

well that's.......a great reason why. I wanted to see if anyone could really tell why they would chose the 325 over the 318. if all you got is "it's got more power", i already know that.

[e30s52]

if it has an lsd in it then thier is your answer. 318 are really tame compared to its big brother if you know what im getting at

[Jean]

I like the nimbleness of the 318i, for autocross you don't need massive amount of power but my m10 of course lacks it. Are you thinking about doing this just for fun or looking to complete ? If you are talking about building a car up specifically for autocross you need to think about what specific class you want to compete in, and evaluate the bugdet / mods for it.

For example, a ST class is going to cost much less than SM or Prepared to be competitive in. Personally I would try both if you can and see which one you like the most. Suspension / tires / driver will be more important in autocross than only power. Since it sounds like your 318i is in better condition, maybe you can add the available superchager if you feel it needs more power and you want to more than just participate for fun :)

[gearheadE30]

I'd say use the M10 car. It is a lot lighter than the 325, and the diff problem is easy to fix ;). There are also a lot of mods around from the 2002 community, and the M10 is a very durable motor. If you want to go all-out, supercharge the m10 (no lag, which is very important) to get some torque.

[ten2doyle102]

i was planning on swapping out the open diff with the lsd down the road too since that's going to a big help.

As for what i wanted to do with it, i was really hoping to get a feel for racing.autocross first so i wanted to make more for fun then really all out competition. Down the road i would like to supercharge it as well for a boost in some power.

Also...i have the m42 motor, it is possible to put a DA supercharger on it correct??? i would just have to swap pulleys and stuff right

i think i am going to switch route and go with the 318 since it sounds a little better than the 325 for autocross.

[GoKart]

I'd say use the M10 car. It is a lot lighter than the 325, and the diff problem is easy to fix ;). There are also a lot of mods around from the 2002 community, and the M10 is a very durable motor. If you want to go all-out, supercharge the m10 (no lag, which is very important) to get some torque.

He has an M42, not an M10.

I say M42 all the way. You can rev it to 7k all day without having to worry about breaking rocker arms.

I have had both cars and will never go back to an M20.

[redhatpat]

Ha ha, this is too funny. The guys with 325s are saying go with the 325 and the 318 guys say go with the 318. :D

Just take out whichever car is in better shape, run a few events, get familiar with the classes, and then decide what you want to do. Both cars will be fun to autox, but one of them may be classed more competitively.










Oh yeah, go with the 325. 4 bangers suck. ;)

[VacMan]

I would highly recommend you send the Eibachs back and get something a lot stiffer. I own a car with Eibach springs and they are WAY too soft for normal spirited driving, much less autoX. Eibach makes a lot of great stuff, but their offering for the E30 is bad news unless you want a 1.5" drop with no better handling than stock.

On your question: I've only driven an E36 318is, but based on that experience I'd say build up your 325. 170hp isn't that much in this day and age, so every little bit helps IMO. I would think you could set up a 325 to handle 99% as well as a 318 and most of us could never tell the difference anyway.

Tim

[ten2doyle102]

I would highly recommend you send the Eibachs back and get something a lot stiffer. I own a car with Eibach springs and they are WAY too soft for normal spirited driving, much less autoX. Eibach makes a lot of great stuff, but their offering for the E30 is bad news unless you want a 1.5" drop with no better handling than stock.

On your question: I've only driven an E36 318is, but based on that experience I'd say build up your 325. 170hp isn't that much in this day and age, so every little bit helps IMO. I would think you could set up a 325 to handle 99% as well as a 318 and most of us could never tell the difference anyway.

Tim

the eibachs i have dealt seemed quite stiffin my opinion. I will have to see how it goes with it. Either i need to get some decent springs seeing as the ones i have now suck major balls! My 318 has H&R's in the rear and some unknown ones in the front. i can always change the springs out late if i dont like the feel.

[ten2doyle102]

Ha ha, this is too funny. The guys with 325s are saying go with the 325 and the 318 guys say go with the 318. :D

Just take out whichever car is in better shape, run a few events, get familiar with the classes, and then decide what you want to do. Both cars will be fun to autox, but one of them may be classed more competitively.










Oh yeah, go with the 325. 4 bangers suck. ;)

4 cyl's aren't that bad you know!!!! i think that i am going to stick with the 318 however. the car is just in much better condition over the 325 i have. it'll be better overall in i think. Personally i don't think that the 325's are going to be that much better.

what are some decent n/a engine mods people are doing to the M42. i planning on rebuilding the top end to the engine and i hear that is where most of the power loss come from. I already have it chipped, k&n, fan delete, ac and ps(soon) delete. so it's relatively quick. i was going to throw in a better clutch and some stiffer tranny and engine mount as well. But what can be done with the head to improve it???

[2002maniac]

I race my 318is in DSP and there my main competition is a guy with a 325is prepped to the exact same level as my car. We run almost exactly the same suspension with the exception of swaybars (he has IE adjustables mine are stock M3/cab). We run the same wheel/tire setup 225 Hoosiers on 15x8 rotas.

We are always extremely close. Sometimes he is faster, other times it's me.

The 318is' lower weight and better balance make up for the deficiency of power. I do take alot of pride in the fact that my "inferior car" is so competetive. Run whichever one seems to be in the best shape.

And I would not run the eibach kit. Those springs are too soft for anything other than a showcar.

[E30Driv3R]

I have a 318iS, and in STX i am usually about 1-1.25 seconds behind the 325 in my class. WE both have coilovers but he has Hawk HP+ and Koseis w/ Azenis. I have stock brakes and Traction T/A.

But now i am going to have to be in SM due to the S50 that will be going in...

[GoKart]

I race my 318is in DSP and there my main competition is a guy with a 325is prepped to the exact same level as my car. We run almost exactly the same suspension with the exception of swaybars (he has IE adjustables mine are stock M3/cab). We run the same wheel/tire setup 225 Hoosiers on 15x8 rotas.

We are always extremely close. Sometimes he is faster, other times it's me.

The 318is' lower weight and better balance make up for the deficiency of power. I do take alot of pride in the fact that my "inferior car" is so competetive. Run whichever one seems to be in the best shape.

And I would not run the eibach kit. Those springs are too soft for anything other than a showcar.

Can you give us a full rundown on the setup in your 318is?