318i mods - United Bimmer Community

**3seriesnut** · 03-14-2009, 05:13 PM

im looking to get a little more out of my old 91 318i. ive allready changed the coils to a hot wound set from bav autosport. im totaly out my element with a gas motor,diesels are more my thing.

a few ideas i had was dumping the stock air box for a tuned alumunium tube ,injectors & rail,pump and regulator. what do you think and what do you recomend?

thanks,mike.

Big Evil · 03-15-2009, 08:16 PM

More flow equals more power. However if you do all that (good mods too) you'll also need to have the heads ported, valves enlarged, and the exhaust modded to support the front half of the engine. Your biggest restriction to flow will always be the curtain area of the valves, be prepared to spend some time to get it right otherwise you end up with more air than the engine can handle (front end) and you actually lose power instead of build it. Same holds true for the exhaust, to much flow equals no backpressure to properly scavenge the cylinders during the overlap period. Lots to consider and calculate to do that stuff right and have it work. Most straight out of the box "bolt ons" really don't quite work unless you do all the stuff the manufacturer did to get their results. Even then, the words "results may vary" is a catch all if you dyno test and lose 20 horse instead of gain it (like no restriction exhaust often does).

**3seriesnut** · 03-15-2009, 08:29 PM

thanks bigevil,i build and tune high performance diesels for a living(pulling trucks and tractors). ive got a spare head for that motor on my parts car. i guess i could tear that head down and do the port and polish and a valve job,put new valves and springs and maybe a new set of cams in and see what i come up with. my exhaust guy is gonna build me a header for it,but that will come after the head work is done. gotta keep the cat here in maryland because damned emmisions testing. what muffler would you recomend? on my 2door 318i ive got a injen muffler on it and it performs ok but the sound is shitty. i was thinking ansa for the muffler or remus? my exhaust guy is good,he builds the tuned headers for my diesels and for a few guys that race gassers at summit point raceway in wva.

this is just a car i picked up for $900 at a auction last week,runs good,got a fresh set of D series stock rims and new tires.

**e30Vichoz28** · 03-19-2009, 04:39 PM

Hey 3seriesnut, i'm from MD too, and i have a 325i; Who is doing the header for u..?? The after market ones r insanely expensive...
Thanks.

**3seriesnut** · 03-19-2009, 05:35 PM

a buddy of mine that does custom exhaust work on the side.

Big Evil · 03-19-2009, 08:44 PM

Flowmaster sounds awesome, but not always the best flow to be perfectly honest. I have gotten good results and noise with just your standard cherry bomb style glass pack. OR just the cats with straight pipes and a hollow muffler case which I know from personal exp is awesome and not even that loud....but you didn't hear that from me :-). Good luck with it though, it sounds like you have what it takers to seriously beef one up, post a vid or something when its up and running

**3seriesnut** · 03-19-2009, 08:58 PM

evil,i use cherrybombs inplace of the resonators to get rid of that "ricey" sound. i picked up a cherrybomb today that looks like a flowmaster 2 chamber. im gonna give it a try. valves will be here tomorow and ill have the head back together saturday and see how it goes. ive got a set of 30lb injectors for it too.

Big Evil · 03-19-2009, 10:04 PM

SWEET, sounds cool

**Birdawg** · 03-19-2009, 11:03 PM

Quote:

Originally Posted by 3seriesnut

evil,i use cherrybombs inplace of the resonators to get rid of that "ricey" sound. i picked up a cherrybomb today that looks like a flowmaster 2 chamber. im gonna give it a try. valves will be here tomorow and ill have the head back together saturday and see how it goes. ive got a set of 30lb injectors for it too.

Let me know how it sounds with the cherry bomb. I have a 318is w/a turbo , straight 3 in. exhaust, and it sound pretty bad. Mine kinda sounds like a Honda

**e30Vichoz28** · 03-20-2009, 02:54 PM

How much does he want for a header...???

**3seriesnut** · 03-20-2009, 05:15 PM

to be totaly honest if my stock header didnt have a warpped flange i wouldnt have changed it. the m42 header is about as good as it gets unless you go long tube but then you lose the flange for your cats,since this car is tagged in wva i dont gotta go thru emmsisions so i went for a longtube stainless header and dropped the cats. long tube stainless or black powdercoated header is $250.00 my price.

**3seriesnut** · 03-20-2009, 05:17 PM

bigdawg,the sound is nice,not ricey and no droning at highspeed. i picked mine up at a local speed shop but you can order one from jegs for like $65.00