Help! The Truth - 4 Cyl Vs 6cyl 3 Series

[Merlin]

Hey guys... fantastic site you got going here...

I trying to clear something up....

Basically what i want to know is if there are any differences in the actual shell / chassis between the 4cyl (318is) and the 6 cyl (325/M3 etc.) .

The reason I am asking is I am looking at getting a 318, with intention of doing a conversion to a 6 cyl motor, but some people are telling me that you have to have a 6cyl beema to start off with as they have more room under the bonnet whilst somebody else says you can still fit 6cyls in.

So can you fit a 6 cyl motor in the 318is's or it just wont work ??

Any help/information/advice is GREATLY appreciated.....

[ganjacyde]

yes it will fit.

[93 325i]

This was brought up yesterday and someone said the mounting points are different. So to do it you'd have to relocate the engine mounts.. And you'd need several other parts than just the engine. It was said to be more cost effective to supercharge the 318

[Merlin]

hmmm... so it can be done... thats the main thing i wanted to know.. thankyou... was more so just a question of physical space..

surely it would b too hard to relocate the engine mounts??

what other stuff would be required... ?

[93 325i]

This was yesterday's convo about this..


QUOTE(SDHAMMER @ Oct 28 2004, 12:26 PM)
Ohhhh... Crap... at least i know that it wouldnt fit.. would a 325i engine fit.. if yes how much for cost?






Same problem. All the 6 cyl models including M3 have the same engine mounting points. So M3 engine would bolt right into a 325. Nothing fits in the 318. Modifying the engine mount locations isn't too difficult. But you would have to change the tranny, clutch, exhaust, differential, suspension, etc. You're looking at about $10,000. I'd rather spend that $3800 on a supercharger and live with less power. At least I wouldn't have to butcher up my car.

[bmw323inewbie]

Maybe buying a 6 cylinder is the answer, problem is putting higher performance engines means you have to replace other parts as well , due to strain etc
I've a 323i and have no mods as yet , had VW Corrado G60 before, supercharged version 1.8L , and reckon 323 is as fast

planning K&N air filter and a twin pipe back box to give it another 15-20 Bhp ( my estimate) bring it up to about 200bhp

[TMac325is]

remember with the added weight you will have to replace shocks, springs, etc to compensate the weight difference

[Brian325i]

Is the reason why you want to put a I6 engine in a 318 because of insurance?

[Furious]

there are a few good threads on what needs to be changed to make a 4cly e36 into any 6cyl.

do a search. use key words like "swap" and such

[steveo34]

I agree with just about everyone post. Its going to be a pretty big hassle. BMW's are not
Honda's. They are a balanced machine. Everything you change or swap will affect the car. Hopefully always for the best!. I would look into the shocks, Fuel lines, Engine mount points and If the 318 shell has the same connection points for the springs and such. I know the 318 has differentr springs/shocks. This would be a problem mounting the front shocks. I would just buy a 325 then do the swap. That way its all there.

Just my 2 cents.

-Steveo

[Autotechnica]

Originally posted by steveo34@Oct 30 2004, 01:48 AM
I agree with just about everyone post. Its going to be a pretty big hassle. BMW's are not
Honda's. They are a balanced machine. Everything you change or swap will affect the car. Hopefully always for the best!. I would look into the shocks, Fuel lines, Engine mount points and If the 318 shell has the same connection points for the springs and such. I know the 318 has differentr springs/shocks. This would be a problem mounting the front shocks. I would just buy a 325 then do the swap. That way its all there.

Just my 2 cents.

-Steveo

[snapback]221111[/snapback]

All E36 non ///M3's share the same rear shocks, the springs are also quite smiliar as the rear of the car the weight is usually the same on 6/4 cyl models. The front of the car uses the same struts for all models (4/6 cyl) 1993 and later. Only the M3 has beefier front and rear dampers. The springs for the front of the 6 cyl is obviously beefier to take the extra weight of the engine. Suspension will not be a huge issue when considering an M3 engine swap into a 318. Probably, you would just have to change the springs. You would definitely want to change the clutch, pressure plate and flywheel to the M3 one. The stock 318 clutch is probably good for about 190-200HP at most, and even that's pushing it.

Other things to change, differential, exhaust, transmission, engine mounting locations, computer, the overall engine, etc. It's not TOO much work. However, as mentioned before, having a 325 does make things easier and cheaper. After dropping in the engine you could easily run around with 325 tranny, diff and suspension parts with no problems at all. Either way, it's your project, so do as you wish. Mint condition E36's are difficult to find these days, so if you've got a good one, my advice is just spend the extra cash on it to do the conversion if you've got the 318.

Bry

[robbins6103]

don't supercharge a 4 cyl. The engine doesn't put out enough power, your best bet is to turbo it if anything....these engine are made to stay NA, so you might even want to consider getting an M3. For the money you're gonna dump into changing out engines you could have yourself a 240 hp M3, with all the suspension and brakes to go with it. Thats my 2 cents at least.

-DR

[bmwfanatice36]

i have a 4cyc, and am considering a supercahrger or turbo, ive heard that supercahrging our car in particular is better than turbo, due to the fact that its a 4cyc, i was told that a supercharger will give it more power

[sabbath130]

this may help.. alotta things talked about here...

http://www.bmw-forums.com/forum/index.php?...20&#entry224945