OK Fellas what gives!!
Thread Starter
Racer
Joined: Oct 2003
Posts: 304
Likes: 0
From: Marlboro NY
OK Fellas what gives!!
This is the chart it was Dynoed before the Accel DFI (speed density) and exhuast upgrade (3 Inch true duals with bullet cats and x pipe).
Hp numbers are way lower than expected...
some major tuning issues I am sure,
What I suspect is really bad wiring.
http://www.ttperformance.net/dyno/larry.jpg
Keep in mind this is with an unlocked converter.
Any ideas why its so low on torque and why the car seem too fall flat on its face at 5500? Check signature for mods. only about 800 rpms of clean dyno.
Hp numbers are way lower than expected...
some major tuning issues I am sure,
What I suspect is really bad wiring.
http://www.ttperformance.net/dyno/larry.jpg
Keep in mind this is with an unlocked converter.
Any ideas why its so low on torque and why the car seem too fall flat on its face at 5500? Check signature for mods. only about 800 rpms of clean dyno.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Well, it's hard to say. One thing I did notice though was that your AFR seems a bit lean, at almost 14:1, then suddenly goes rich to about 12:1. I'd be shooting for about 12:9, who did the programming?
Thread Starter
Racer
Joined: Oct 2003
Posts: 304
Likes: 0
From: Marlboro NY
I am not sure what the deal is with the programming and thats the reason why I am switching to the accel dfi gen VII standalone.
It is a TPIS level 6 chip.
my question is: why does the motor seem to break up or lose power when it started to run rich.
This motor has pulled accidentally to 7900 rpm quickly in second gear (on playback tach) I cant imagine it doing that with the torque falling off at the rate that it does on that dyno sheet. My stock wiring is junk and the dfi should cure that.
shouldn't this motor peak hp about 6200 - 6400 rpm?
It is a TPIS level 6 chip.
my question is: why does the motor seem to break up or lose power when it started to run rich.
This motor has pulled accidentally to 7900 rpm quickly in second gear (on playback tach) I cant imagine it doing that with the torque falling off at the rate that it does on that dyno sheet. My stock wiring is junk and the dfi should cure that.
shouldn't this motor peak hp about 6200 - 6400 rpm?
Thread Starter
Racer
Joined: Oct 2003
Posts: 304
Likes: 0
From: Marlboro NY
420 cube 11.28:1 compression
AFR 210 cc heads
4340 Eagle Stroker assembly assembly with 6" H beam rods
JE Custom Pistons
Cam is a TPIS 700-701 w/ 1.6 rockers
248, 248 @ .050
.659, .661 lift
110 LSA
The exhuast is TPIS 1 3/4 primarys into TPIS front Y then to Random Tech Cat , and dynomax ultraflow rear Y and Flowmasters (the whole system is 12 years old).
The cam should peak higher than 5500 with a port matched and cleaned up miniram right?
Why is it falling flat on the dyno when it pulls like crazy well past 7500 rpms.
If it is running rich then it isnt a fuel delievery problem.
Also wouldn't you think the torque would be a little higher than 340 at its peak?
AFR 210 cc heads
4340 Eagle Stroker assembly assembly with 6" H beam rods
JE Custom Pistons
Cam is a TPIS 700-701 w/ 1.6 rockers
248, 248 @ .050
.659, .661 lift
110 LSA
The exhuast is TPIS 1 3/4 primarys into TPIS front Y then to Random Tech Cat , and dynomax ultraflow rear Y and Flowmasters (the whole system is 12 years old).
The cam should peak higher than 5500 with a port matched and cleaned up miniram right?
Why is it falling flat on the dyno when it pulls like crazy well past 7500 rpms.
If it is running rich then it isnt a fuel delievery problem.
Also wouldn't you think the torque would be a little higher than 340 at its peak?
Safety Car
Joined: Sep 2001
Posts: 4,160
Likes: 554
From: Glenbeulah Wi
Originally Posted by Gold1986Vette420
420 cube 11.28:1 compression
AFR 210 cc heads
4340 Eagle Stroker assembly assembly with 6" H beam rods
JE Custom Pistons
Cam is a TPIS 700-701 w/ 1.6 rockers
248, 248 @ .050
.659, .661 lift
110 LSA
The exhuast is TPIS 1 3/4 primarys into TPIS front Y then to Random Tech Cat , and dynomax ultraflow rear Y and Flowmasters (the whole system is 12 years old).
The cam should peak higher than 5500 with a port matched and cleaned up miniram right?
Why is it falling flat on the dyno when it pulls like crazy well past 7500 rpms.
If it is running rich then it isnt a fuel delievery problem.
Also wouldn't you think the torque would be a little higher than 340 at its peak?
AFR 210 cc heads
4340 Eagle Stroker assembly assembly with 6" H beam rods
JE Custom Pistons
Cam is a TPIS 700-701 w/ 1.6 rockers
248, 248 @ .050
.659, .661 lift
110 LSA
The exhuast is TPIS 1 3/4 primarys into TPIS front Y then to Random Tech Cat , and dynomax ultraflow rear Y and Flowmasters (the whole system is 12 years old).
The cam should peak higher than 5500 with a port matched and cleaned up miniram right?
Why is it falling flat on the dyno when it pulls like crazy well past 7500 rpms.
If it is running rich then it isnt a fuel delievery problem.
Also wouldn't you think the torque would be a little higher than 340 at its peak?
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I picked up close to 25 rwhp and 40 rwtq going from a single 3" pipe with a gutted car to a single 4" pipe. I had to add 6-7% more fuel everywhere after the 4" exhaust.
Thread Starter
Racer
Joined: Oct 2003
Posts: 304
Likes: 0
From: Marlboro NY
I should be getting my car back from TTP in New Jersey on sat the 13th. I am hoping to have a new Dyno sheet to post at that time.
They are changing my exhaust over to a dual 3" with bullet cats and a x pipe.
They are also installing a full manual valve body in my trans so I am hoping for a more complete dyno sheet next time around.
I also brought them a Accel Gen 7 dfi to install but they changed their mind about installing it as they said they are too busy to get into a "project" at that time. (they primarily tune LSx motors). And they don't normally deal with 20 year old cars.
Will keep you guys posted.
Thanks again for the info.
Larry
They are changing my exhaust over to a dual 3" with bullet cats and a x pipe.
They are also installing a full manual valve body in my trans so I am hoping for a more complete dyno sheet next time around.
I also brought them a Accel Gen 7 dfi to install but they changed their mind about installing it as they said they are too busy to get into a "project" at that time. (they primarily tune LSx motors). And they don't normally deal with 20 year old cars.
Will keep you guys posted.
Thanks again for the info.
Larry
Thread Starter
Racer
Joined: Oct 2003
Posts: 304
Likes: 0
From: Marlboro NY
Update And Questions
Sorry for pulling this dead thread from the archives fellas.
UPDATE:
I finally got the Car back from the shop on the 15th of JULY and it still doesn't have a good exhaust on it. All they did in 3 months was a TCI full manual Valve Body.
I had them put the exhaust back to what I drove there with due to 3 month wait.
Should I go all out with the exhaust or leave it minus the CAT and add dumps?
What kind of mufflers flow the best with the least amount of noise?
I am thinking 3" mufflers and an xpipe duals. Does anyone know the CFM Flow and Decibel level of 3" Corvette mufflers?
I am in search of that magical 400 RWHP unlocked on a Dynojet.
It still has the stock MAF (minus screens).
Tuning is a mile off.
What should I expect from Tuning and Less Restrictions both intake and exhaust?
I have been tempted to run it in the 1/4 but the car runs a bit rough at the moment with the 20 year old computer running this beast.
UPDATE:
I finally got the Car back from the shop on the 15th of JULY and it still doesn't have a good exhaust on it. All they did in 3 months was a TCI full manual Valve Body.
I had them put the exhaust back to what I drove there with due to 3 month wait.
Should I go all out with the exhaust or leave it minus the CAT and add dumps?
What kind of mufflers flow the best with the least amount of noise?
I am thinking 3" mufflers and an xpipe duals. Does anyone know the CFM Flow and Decibel level of 3" Corvette mufflers?
I am in search of that magical 400 RWHP unlocked on a Dynojet.
It still has the stock MAF (minus screens).
Tuning is a mile off.
What should I expect from Tuning and Less Restrictions both intake and exhaust?
I have been tempted to run it in the 1/4 but the car runs a bit rough at the moment with the 20 year old computer running this beast.
Last edited by Gold1986Vette420; Aug 3, 2006 at 12:22 PM.