Quickest E30 318is.. how to do it?

hello...it is the stupid questions time again... I've resolved all my oil leak issues...  now the car is just sweet... but i need to ask a question(s)..

is it possible to make a 318iS quick enough to give a standard E30 325i run for its money..? maybe not beat it, but make the guy think...hahaha I'm not talking about Motorway speeds.. more like 0-60 times...  I've seen a couple of 325i boys(racers) with big alloys and sh*te... and u can tell they've never seen a 318is... and they go up ur ass just cause it says 318 at the back and try and take u... but at the mo there is no point me racing yet... i know if we did race, the 325 would eat me up... 

so whats my options? preferably no turbo's... or nitrous... all normally aspirated upgrade details please... if it is possible....

I've had to race some 320i boys.. again with their BIG 17's -18's allows and sh*te.. but they had to be beaten... have to say though a 320i with fat exhaust sounds just as mean as a 325....

I have a standard 318iS.. with 14in BBS.. all original... 115000 on clock... I have to say the car flys... but how fast would it fly next to a 325i???

Edited by beema318is

that is true jonp... the car is bloody efficient... im still quiet surprised at that.... I'm getting some really good MPG...

 

 

 

 

have a look at our own B318isP's website
www.esatclear.ie/~bpurcell
This guy has done a number of mods to uprate the car (chip, panel filter, suspension, etc.)
(still slower than my e30 320i SE - but then again that was on an economy run )

Thanks for all the feedback... i know the 325 has about 35-40 bhp extra... but than it also weighs a bit more .. so its true if i lightened the car and do some mods on the engine it should be possible... I also read somewhere that the 4 pot E30 handle little easier/better than the 6 pots due to a lighter engine and better weight distrbution... so around twists and turns a 325(unmodified) should have quiet a challange against a 318is... do all 325's have m-tec suspension??  and sports seats etc.. ? o yeah and if someone has like 17/18's on a standard 325 that should drop there performance a little shouldnt it.. ?

personally i think the iS is perfectly balanced.. not talkin about performance but it is the best car ive ever driven...

Well the 325i gives up 70kg to the 318is so that's a start and they do say that the 4pot e30 is more balanced than the heavier 6 pot lump though I wouldn't necessarily agree with that where the touring is concerned as the weight distribution is better than the saloon (being a tourer owner I would say that eh? hmmm)  and they do have the heavier duty Mish suspension set up.

With 17"/18" wheels, their car would be slower accelerating if they don't use the correct profile tire to keep the rolling diameter of the wheel the same as stock and it ended up larger. They may have better handling than standard though (in dry anyway) with their larger wheels and rubber.

Only the 325iS had the full M-tech setup, I believe, though your 318is should have the stiffer M-tech springs and shocks 2, minus the thicker roll bars.

Hi sir,

is that what you call a moderator?

Don't really want to try to split hairs but with regards to the extra rotational inertia for bigger wheels, I thought that would be reliant on total unsprung weight? If the new, larger wheel and tyre weight is the same as stock, due to newer, lighter wheel materials used, and the same rolling diameters, then would the unsprung weight's inertia not balance out? i.e. would require the same energy input to move? There are variables though?

So really a 318is has a better suspension setup to a standard 325i?

Madrab I'm going to take your advice on some of the engine mods... ie.  free flow panel air filter/induction kit, free flow exhaust manifold and system and an ECU swap. And see how we go... Has anyone else already got a similar setup on a 318is?

And the tourer 325i probably is better balanced than a saloon.. for obvious reasons... but is it quicker than a saloon in a straight line?

Oh yes mini's with that sort of power are stupid! But are a giggle! You could get one as a second car..325? No problem!

Yep beema it sure does.

From the info I gathered the 318is was modelled on the 325is chassis with the better tuned chassis and slightly different suspension set up but was all M-Tech qualified spec.

The quoted figures I've got for a stock 325i is 136mph whereas the Tourer is 133mph. Mine isn't standard though and have had some fun with same type of 325i owners that I think you are talking about. I've had the speedo just over the 140mph mark though but haven't managed to get an accurate 1/4 mile yet to confirm what the top speed is. 0-60 time is approx 7sec.

Madrab, unsprung weight has nothing to do with acceleration. For a wheel, it has to be accelered in two dimensions - straight (like the rest of the car) and rotationally (around its axle). The rotational interia is based on a radiused squared formula - so the further out the weight is on the wheel then the more inertia it has - the flywheel effect (even if the overall weight can be kept the same).

Unless you spend silly money, modern alloys are not a lot lighter than wheels from a few years ago - actually some designs are extraordinarily heavy.

Unsprung weight affects how quickly the wheel moves in relation to changes in the road surfaces.

Edited by b318isp