Im sure im gonna get flamed for this post... cause i usually do not like racing another fellow BMW owner...but since i have no road race (track) or exciting drag strip stories to tell you... i thought i contribute with this little story i have encountered awhile ago when i first got the turbo system on my 93 325is. Several years back i was in the bay area spectating an custom import show, afterwards when everybody got out of the show... there were all these acuras/hondas, toyotas, and so on cruising around the convention area. As i was turning out of the parking lot... i noticed a black E36 M3 following me out. As we stopped at the light... the guy in the M3 started to rev his motor and in the process i heard his blowoff valve go off. I thought "hmmmmm... this guy must have a turbo or a supercharger" and didnt think much of it after he burned out of the intersection and took off... but then he slowed down a bit to let me drive up next to him. At that moment, i had to shift and my blowoff went off (anybody who doesnt know how loud Blitz Blowoff valves are... they are equivalent to a semi truck's air brakes or whatever makes that "shhhwwwooooosh" sound) because of that... the passenger in the M3 rolled down his window and started to talk crap about how my car is a M3 "wanna-be" and all that. (i have an M3 front bumper, and mirrors - but i had to get the m3 bumper cause the AA intercooler wont fit on a stock 3 series front end..and as for the mirrors...i like the way they look.) Anyways... i just ignored him...and downshifted to 3rd and took off and slowed down again. Then the passenger yelled out asking if i wanted to run against the M3. I leaned out and agreed reluctantly to the duel. (i figured ... if i lose... i have an excuse...325's are meant to lose to M3's and plus i wanted to know how my car would hold up to a blown M3). He told me to follow him to a nearby remote area... where there was a long straight-away, nobody around except his other friends and my friends that followed to this area. Once there, we chatted a bit and found out that he had a RMS supercharger with 'this and that' bolt ons. I told him that i had only a AA stg1 turbo w/ stock motor and minor bolt ons as well. He grinned slightly and told me to line up where a one of his friend was flagging us down. Well... not to make this story longer... we both started from a dead stop and took off. Out of the hole... the M3 was pulling hard away from me... but as i shifted into 2nd... he wasnt pulling away from me anymore...i was starting to creep up...and then by the time i got into 3rd...i was already next to him...and at the end of 3rd gear...i was a good 1/2 car length ahead..and the rest was history. Afterwards, that pissed him off so badly...he got one of his friend's built twin turbo supra to go against me also... i got my ass spanked by the supra... but then again... i thought..."ehhh i only have a 325" ... at least i beat a cocky guy in a blown M3.
*now dont do this at home... street racing is illegal, so keep the racing on the tracks*

Nice goin! That guy in the M3 got what he deserved for talking to another bimmer owner like that.
We're all brothers here, why the hate?

:confused:

I always give plenty of respect to anyone with a roundel, whether it's brand new, old, or a POS.

funny how the PASSENGER was the one talking crap to u. I would have said get your own car and then we can talk. Its not cool how some people have no respect for thier own kind....m3 or not. Way to put him in his place.

Did you do an engine coversion?
2.8 litre?
325is has 2.5l...
I had a non-Vanos 92 325 is, and it was quick as hell.
I put a crazy 3:91 gear ratio with pulley/header/chip/intake in and I was killing lightly modified M3s from 35-120mph. After that they got me. But we rarely had to go there...
I can imagine that car with a turbo would have been serious trouble even to a blown M.(Which I have now)
You start doing 12s in the quarter, and lots of cars are going to lose to you.
:D
Enjoy
Nice story!
G

How do you get a blowoff valve sound from a supercharger?

Thanks for the support guys... like i said before...we are all BMW enthusiasts...and the last thing i wanted to do is be in a race against another fellow BMW enthusiast.

Anyhow to answer Vishal's question... I dont know if this is the same theory for blowers...(other than just sounding cool) but you can get a blowoff valve for your supercharger... the reasons why turbo motors get a bypass or a blowoff valve is to release this sudden rush of forced/compressed air from going back into the impeller of the turbo and it trys to force the impeller to go the opposite direction, when you lift off the throttle and the throttle body butterfly closes...if this forced air is not released...it may cause damage to the turbo... most turbo kits come with a bypass valve... and i know most of the Mustang supercharger kits came with one too..but did the Dinan kit come with one?

Greg... yes i just had a swap job done with a 2.8 liter engine recently...retaining the same OBD I system and 2.5 liter intake manifold. How did you like your 3:91? was it in a automatic or 5 speed?
Well anyways...again..thanks for the support guys.

Oh yeah another thing... i know for a fact that my car wasnt pulling more horsepower than that M3... when it comes to drag racing...everything plays a major factor than just pure horsepower... it could have been my shorter rear end gearing, driving characteristics, tire compound, weight distribution or anything. I admit that im not the greatest drag racer... but Im sure that if TampaTurboM3 was driving that guys blown M3... he could have probably spanked me badly...who knows... i just got the better edge for that particular race.

"Remember...when you think you have a fastest BMW... there will always be someone with a faster and more powerful car than you. (Unless you're TampaTurboM3...nothing can touch you~!)

Originally posted by TurboBMW3
Oh yeah another thing... i know for a fact that my car wasnt pulling more horsepower than that M3... when it comes to drag racing...everything plays a major factor than just pure horsepower... it could have been my shorter rear end gearing, driving characteristics, tire compound, weight distribution or anything. I admit that im not the greatest drag racer... but Im sure that if TampaTurboM3 was driving that guys blown M3... he could have probably spanked me badly...who knows... i just got the better edge for that particular race.

"Remember...when you think you have a fastest BMW... there will always be someone with a faster and more powerful car than you. (Unless you're TampaTurboM3...nothing can touch you~!)

You might have the same HP peak as the SC M3, but I bet your over all torque curve is higher. This will explain you pulling on him. I think a stage 2 Dinan SC puts about 245 rear wheel torque to the ground (310 at the crank) throughout the whole rpm band BUT i seem to remember that most of the stage 1 level AA turbo will put close to 300 rear wheel torque with the same HP. Their torque figures will drop at the higher RPM.

The 3:91 was just an experiment. Nothing I would reproduce or recommend unless your at a short race track or you autoX a lot. The top end in the 325 was 125 at full redline.
Cruising at 70 meant 4000+rpms! That was tedious. Even though Fifth gear felt more like fourth.
What made it fun was being in thrid, and having instant power like second gear even low in the revs.
If you really want different gearing, go with 3:38(or 3:36) which came in the automatic M3s. I have the standard 95 M3 3:15, but I still have 2 old diffs from the 325, so I will build a 70% lockup 2:23, just to have a mild increase in torque but not a scarifice in top end or cruising rates.
G