Is your car an auto? If so, thats about the times you should be getting stock. These cars are not made for street racing/off the line acceleration. You should buy an old american V8 muscle car.
i have a 1989 535i and i recently installed the performance head from metric mechanic i do alot of street racing i i run against some fast cars and win by a few car lenghts but yesterday i took my car to new england dragway and i coulndn't get no better time then a 16.2 but the guys that i street race with where getting time of 14.8 i want to know y i wasen't no where near there time if my car is faster then thiers
Is your car an auto? If so, thats about the times you should be getting stock. These cars are not made for street racing/off the line acceleration. You should buy an old american V8 muscle car.
Lowered with blue h&r(?) springs, Bilsteins, tint, 19# design 3 injectors, Dual Magnaflow
southwest WA
Originally Posted by Alexlind123
no my car is a manual with a 3.91 diff
do a dyno run and see what your torque curve looks like, there could be something interfering with proper engine operation.
Originally Posted by BillionPa
what kind of things are we talking about that can be interfering i'm thinking of now putting in bigger injector and a adjustable fuel pressure regulator maybe this will help
Hmm........... You sound like a troll.....
Answer these questions for me and I'll be able to help:
1. what cam are you running?
2. what chip are you running?
3. what rpm are you shifting at?
4. why would you put in an adjustable reg on a stock motor (head doesn't count)?
5. what exhaust are you running?
6. what headers are you running?
7. why go for bigger injectors if all the manifolds are stock and you run the flap type AFM?
8. why wouldn't you turbo it?
Who fitted the new head? the valve timing could be off by a tooth.
"3.91" diff ratio HMMMMMM don't think so...... try 3.90.
Last edited by Ausmpower; 06-19-2006 at 02:44 AM.
BMW parts professional
Previous rides:
BMW
E12 M535i (go the dogleg!)
E28 M535i (MMM M88!)
E34 535i M
MAZDA:
RX7 S-IV T04 (440 hp ATW)
RX7 S-I 13b bridge port
RX4 13b peripheral port
i'm using a 272 cam with a jim c chip, i shift at the 6800 mark and i figure a adjustable reg to add more gas to compensate for the extra air from the ported head, the headers are stock can't find and a performance set, exhaust is stock, the manifold is also ported ,don't have enouggh money for turbo and i will check the timing cuz that could be an issue and what u mean not 3.91Originally Posted by Ausmpower
O.k you have a ported head (with a debatable flow increase) but it is still choked by the stock exhaust and AFM so your gain would be negligable.Originally Posted by dom85m30
If it IS flowing any more air than stock the AFM would compensate anyhow and the EGO would stop it going lean. I have yet to see an NA M30 go lean with bolt on mods if the fuel pump is healthy.
I'd be looking at getting the cam timing checked first, then fit a free flowing exhaust, MAF conversion (then dyno it to see you've only gained 20 hp).
Diff is 3.9 not 3.91 ratio unless it's not an E34 diff....
What "272" cam is it (brand)?
How much lift?
Hollow or Solid?
BMW parts professional
Previous rides:
BMW
E12 M535i (go the dogleg!)
E28 M535i (MMM M88!)
E34 535i M
MAZDA:
RX7 S-IV T04 (440 hp ATW)
RX7 S-I 13b bridge port
RX4 13b peripheral port
ok i understand that i need the exhaust done and a maf coversion i just don't understand why it is running slower then when it had the factory head and would u know of a place where i can get the headersOriginally Posted by Ausmpower
My advice: Stop street racing- stick to the dragstrip.
If the diff is a 3.9X, then it's a 3.91, not a 3.90- but it doesnt' really make a difference. Basically a 3.91 diff has 43 teeth on the ring gear and 11 teeth on the pinion, making it a 3.90909090909090909090909 ratio- if you want to get nitpicky. :P
Bret.