Why is my car slow?

**RealLiveMD** · 03-09-2008, 06:18 PM

I have an 02 WS6 Pat stg II heads, cheater cam, jet hot headers, ls7 clutch, upgraded t-56 with stock 3.42's. 394rwhp, 386 tq. I can't whip a stock 03 Z06, I even switched cars. Also, I tested myself against a firehawk vert. and only pulled him by a car. I'm thinking traction may be one of my issues given when I drove the vert and punched from 3grand, the car digs and pulls, My car wheel hops and roast the tires at 3, 5, and 6k. I actually have the better tires. The car just doesn't seem to pull hard inspite of the dyno torque numbers being above stock everywhere. What can be the problem. I need to fix it quick. The ZO6 raped me on the highway. I used to run with Z06's when I was stock. .

**Y2KPewterSS** · 03-09-2008, 06:21 PM

Who did your tuning?

394 RWHP isn't very good for your mods.

**RealLiveMD** · 03-09-2008, 06:25 PM

Originally Posted by Y2KPewterSS

Who did your tuning?

394 RWHP isn't very good for your mods.

local company called xtreme auto accessories, but, I have the dyno sheet and I even had another company dyno the car because I didn't believe it had 390's given the way it feels.

**Y2KPewterSS** · 03-09-2008, 06:32 PM

Lot of reasons why your car might be slow. How is your rearend? It could be going out causing you to be slow. What intake are you running, LS6 intake? Do you know what your air/fuel ratio is? Maybe your tranny isn't healthy, even though you had it upgraded. A heads/cam M6 LS1 should be putting down 420 RWHP range.

**310stanger** · 03-09-2008, 06:34 PM

That car should be well over 400rwhp with those kind of mods, 390 sounds pretty weak. I would take it to a good shop and have them check everything over and then redyno. Something is wrong dude.

**GTP231** · 03-09-2008, 06:37 PM

Start with getting rid of that stock 10 bolt and get something stronger and 4.10s. Second get a new tuner

**Nhra Firebird** · 03-09-2008, 06:37 PM

friend of mine has the same cam and heads you have... I think he is putting down around 430's

**310stanger** · 03-09-2008, 06:41 PM

His rear could be shot, but this isnt why he is about 50 horses short at the wheels lol I wonder if his engine is completely healthy and whether or not his a/f is correct.

**Y2KPewterSS** · 03-09-2008, 06:42 PM

Originally Posted by 310stanger

His rear could be shot, but this isnt why he is about 50 horses short at the wheels lol I wonder if his engine is completely healthy and whether or not his a/f is correct.

Pretty much what I am thinking

**RealLiveMD** · 03-09-2008, 06:42 PM

the tranny was stock, then I sent it to T56 rebuilds. No improvement. The rearend is roaring or anything. I know that if I removed my cats and went with a FAST over an ls6 then I should get at least into the 410-415 range. However, even with 390, I should be able to run a 360 hp Z06 shouldn't I?

**Y2KPewterSS** · 03-09-2008, 06:43 PM

Originally Posted by RealLiveMD

the tranny was stock, then I sent it to T56 rebuilds. No improvement. The rearend is roaring or anything. I know that if I removed my cats and went with a FAST over an ls6 then I should get at least into the 410-415 range. However, even with 390, I should be able to run a 360 hp Z06 shouldn't I?

Not necessarily, Z06s weigh considerably less than fbods.

**RealLiveMD** · 03-09-2008, 06:43 PM

I'll look for the dyno sheet and try to post it, However, the local mustang shop Dynospeed said the af could be slightly improved but was pretty good.

**Tyler_LS1** · 03-09-2008, 06:44 PM

What kind of suspension mods do you have?

**Y2KPewterSS** · 03-09-2008, 06:44 PM

Originally Posted by RealLiveMD

I'll look for the dyno sheet and try to post it, However, the local mustang shop Dynospeed said the af could be slightly improved but was pretty good.

Just look at your dyno sheet, it should be in the 11, 12, 13 range and just tell us where its at.

**310stanger** · 03-09-2008, 06:45 PM

Originally Posted by RealLiveMD

the tranny was stock, then I sent it to T56 rebuilds. No improvement. The rearend is roaring or anything. I know that if I removed my cats and went with a FAST over an ls6 then I should get at least into the 410-415 range. However, even with 390, I should be able to run a 360 hp Z06 shouldn't I?

with 390, the gearing, aerodynamics, and WEIGHT of a c5z06 is hard to overcome. The main issue is that a car with stage 2 patriots should dyno way higher then that.

**Y2KPewterSS** · 03-09-2008, 06:47 PM

Originally Posted by 310stanger

with 390, the gearing, aerodynamics, and WEIGHT of a c5z06 is hard to overcome. The main issue is that a car with stage 2 patriots should dyno way higher then that.

Lots of guys with M6, LS1s, stock heads and huge cams dyno in the 390, low 400 range. That should put into perspective just how low your dyno #s are with stage 2 heads.

**310stanger** · 03-09-2008, 06:48 PM

Originally Posted by Y2KPewterSS

Lots of guys with M6, LS1s, stock heads and huge cams dyno in the 390, low 400 range. That should put into perspective just how low your dyno #s are with stage 2 heads.

rev it up dynoed 400rwhp with jus a big cam and bolt ons.

**2MuchFun** · 03-09-2008, 07:16 PM

you say it was a mustang dyno?

**RealLiveMD** · 03-09-2008, 07:41 PM

Originally Posted by 2MuchFun

you say it was a mustang dyno?

no both dyno's were dynojet. It's just the second dyno was done by Dynospeed, a company known for doing mustang work. I guess I have to drive to thunder racing. I called but they are about 2 months out on open slots and 6 hours away.

**310stanger** · 03-09-2008, 07:43 PM

Originally Posted by RealLiveMD

no both dyno's were dynojet. It's just the second dyno was done by Dynospeed, a company known for doing mustang work. I guess I have to drive to thunder racing. I called but they are about 2 months out on open slots and 6 hours away.

a company that is known for working on mustangs is used to low dyno numbers obviously.