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View Full Version : whys my car sooo slow



socalfandabodys
10-01-2004, 08:41 PM
My car seems to have no balls until it gets to the 3000 rpm range. The problem is I have a overdrive trans so it never gets there but when I get close to 3000 rpms it seems to. It is a chevelle with 3.31 eaton posi rear end. It has a bowtie overdrive stage two trans with a tci saturday night special torque converter with a 1800 stall. It also has a bbc 396 with keith black 9.5:1 compression,bored .30 over,polished crank and rods,mild comp cam,edelbrock performer heads,edelbrock air gap manifold,headers,and a speed demon 850 cfm carb. It has a B and M pro ratchet shifter. whats a safe rpm to take this car to in 1st, 2nd, 3rd. what are the ideal shift points. The car makes awesome torque on desktop dyno 400 @2000 rpm but only about 165 horse @2000. with a max of about 440 horse @5000 rpm and 470 torque @5000 rpm. Whats the problem am I doing something wrong.

dennis68
10-01-2004, 09:15 PM
Please post ALL specifics so we can determine if this is tuning, improper part selection, or something maybe went wrong. Sounds like fuel/timing concern. Maybe no advance, or too much/not enough fuel during transition. Is the Demon a double squirt? I would hope not on a mild cam, automatic, geraed for cruising car.

socalfandabodys
10-01-2004, 09:59 PM
dennis thanks for the reply. I think its a single squirt carb but it feels like it may be even something in the tranny. By the way it has 1.75 ratio roller rockers. I will get the head and cam specs later tonight.

ProdigyCustoms
10-02-2004, 04:54 AM
As Denny aluded to, timing, or the timing curve, could be a big issue. What distributor is in it? Have you checked timing at various RPMs to see what the timing is at different RPMs? Most aftermarket distributors are set up factory with 20 degrees advance, and are usually all in by 2800-3000 or so, so you need about 14 initial to get 34. Curve kits can be purchased to bring it in faster? Or bring in more? A dvance light light would tell the story.
The 3.31 gear in a 3900LB car with a tight converter and a short stroke motor is helping things either. Add an inefficient tranny, some tall tires and miss the une up a little, and we have a stone.
Get those detail Denny asked for, everything you can think of.

MrQuick
10-02-2004, 06:54 AM
Sounds like a combination problem to me too. You car is no where near its power range at take off, whats your flash RPM at launch... around 2000 prm then catches up? Your engine would probably performe better with a 3000-3200 stall converter and more timing.