My first dyno== SAD =(
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
Re: My first dyno== SAD =( (jparr)
Where did your peak hp and torque occur ? You couldn't possibly be making your power up at 5500 rpm with that set-up.
You need to scrap your tpi intake manifold right away, but you have other problems too. Your set-up should probably be right around 300 rwhp with that stock tpi on it provided your heads flow 225+cfm.
good luck
Beach Bum
You need to scrap your tpi intake manifold right away, but you have other problems too. Your set-up should probably be right around 300 rwhp with that stock tpi on it provided your heads flow 225+cfm.
good luck
Beach Bum
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: My first dyno== SAD =( (jparr)
Don't panic yet. Since the torque goes straight down, it must be something pretty basic and pretty drastic. And hopefully, easy to find.
1. Check throttle to insure it is opening all the way. Have someone floor it and check throttle plates. Insure nothing is blocking anything from aircleaner to throttle blades.
2. Check that all cylinders are firing by quickly touching exhaust manifold or plugs after 1 minute warm up. Should all be about same temp.
3. Check ignition advance. Should be about 35 degrees total advance all in by 2500 to 3000 rpm.
4. Chech that cats or exhaust system is not plugged. Should not sound like loud hiss at fast idle.
5. Check that there are no codes.
1. Check throttle to insure it is opening all the way. Have someone floor it and check throttle plates. Insure nothing is blocking anything from aircleaner to throttle blades.
2. Check that all cylinders are firing by quickly touching exhaust manifold or plugs after 1 minute warm up. Should all be about same temp.
3. Check ignition advance. Should be about 35 degrees total advance all in by 2500 to 3000 rpm.
4. Chech that cats or exhaust system is not plugged. Should not sound like loud hiss at fast idle.
5. Check that there are no codes.
Melting Slicks
Joined: Sep 2000
Posts: 3,150
Likes: 1
From: Carlsbad, CA CA
Re: My first dyno== SAD =( (BBA)
Am I the only one that sees there is something wrong with this dyno graph? Your torque should be relatively flat, and it shouldn't drop off like that. It almost seems like you are letting off the gas! The Hp is climbing but it also looks a little shakey. I would trouble shoot either your ignition system or your fuel system. There is no way your torque should drop off that drastically in that early in the RPM range.
Drifting
Joined: Jun 1999
Posts: 1,874
Likes: 1
From: Garden Grove CA
Re: My first dyno== SAD =( (jparr)
There is a bottleneck in your engine - I too wonder about your cat conv. I'm also curious about your ignition and fuel curves, to me the dyno chart shows a fuel starved engine. I can't see the rest of the posts from this screen, but what size fuel injectors are you running (don't answer if it is listed in the other replies). You could just as easily be the victimn of a weak fuel pump.
Going to a dyno without computer logging data from your car's ecm is a general waste of time on an efi engine. Even better is a wide band air/fuel sensor plumbed in ahead of the cat conv.
Thomas
Going to a dyno without computer logging data from your car's ecm is a general waste of time on an efi engine. Even better is a wide band air/fuel sensor plumbed in ahead of the cat conv.
Thomas
Le Mans Master
Joined: Jan 2002
Posts: 7,460
Likes: 5
From: Burnet, TX
Re: My first dyno== SAD =( (zelement)
You need headers.
Make sure you have the correct Air/Fuel ratio also.
My '84 Crossfire Dyno'd 200RWHP. You should be well above 300 with your mods if you get headers and check your air/fuel.
Ignition may be another thing to check.
Make sure you have the correct Air/Fuel ratio also.
My '84 Crossfire Dyno'd 200RWHP. You should be well above 300 with your mods if you get headers and check your air/fuel.
Ignition may be another thing to check.
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Racer
Joined: May 2001
Posts: 320
Likes: 0
From: TX
Re: My first dyno== SAD =( (Red84CrossFire)
I may be crazy, but aren't HP and torque supposed to be the same at 5252 RPM? Something is screwy.
How is the sotp power? Does it feel stronger than the stock engine? Do you have any timeslips?
How is the sotp power? Does it feel stronger than the stock engine? Do you have any timeslips?
Thread Starter
Drifting
Joined: May 2001
Posts: 1,392
Likes: 0
From: Wabash,IN
CI 7-8-9-10 Veteran
St. Jude Donor '08
Re: My first dyno== SAD =( (jparr)
i have never had this car to a track yet!!! yes this car has more ***** then the old motor i have street raced a v8 forumla and a lt1 camaro these cars didnt have a chance at low end but on the top end they would walk me !!!
i know i need heads and headers and a good exh system and maybe do away with the tpi set up and go sr or mini but this is my first dyno like it says my car should (i feel) at least 300 325 hp i even did it on desktop dyno adn thats what i cam up with its weird to me JAY
i know i need heads and headers and a good exh system and maybe do away with the tpi set up and go sr or mini but this is my first dyno like it says my car should (i feel) at least 300 325 hp i even did it on desktop dyno adn thats what i cam up with its weird to me JAY
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: My first dyno== SAD =( (The Green Rocket)
I agree. Something is drasticly wrong. Its acting like you are only opening the throttle half way, or you are getting half the fuel, or no timing advance.
I would not look at the horsepower numbers right now. Remember, HP is just a formula which is: (RPM x TORQUE)/ 5252. Just look at the torque curve. I would expect to see even a mild cam 383 torque to increase from 2500 thru 3500 with at least 350 ft lbs. Your engine's torque drops ---dramatically. More tests are necessary to find out if the problem is air or fuel. If you are not getting enough fuel, it should show up on the dyno's AFR graph. I hope you can have that tested. If the AFR is 12.5 - 13.0 its OK. Then it has to be an airflow problem somewhere or lack of timing advance.
Best best is to have someone that knows what they are doing at the dyno shop look at it and tell you if its air or fuel problem.
I would not look at the horsepower numbers right now. Remember, HP is just a formula which is: (RPM x TORQUE)/ 5252. Just look at the torque curve. I would expect to see even a mild cam 383 torque to increase from 2500 thru 3500 with at least 350 ft lbs. Your engine's torque drops ---dramatically. More tests are necessary to find out if the problem is air or fuel. If you are not getting enough fuel, it should show up on the dyno's AFR graph. I hope you can have that tested. If the AFR is 12.5 - 13.0 its OK. Then it has to be an airflow problem somewhere or lack of timing advance.
Best best is to have someone that knows what they are doing at the dyno shop look at it and tell you if its air or fuel problem.
Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: My first dyno== SAD =( (The Green Rocket)
Am I the only one that sees there is something wrong with this dyno graph? Your torque should be relatively flat, and it shouldn't drop off like that. It almost seems like you are letting off the gas!
There is a bottleneck in your engine - I too wonder about your cat conv.
You could just as easily be the victimn of a weak fuel pump.
Burning Brakes
Joined: Sep 2000
Posts: 1,199
Likes: 1
From: NewCastle IN. USA
Re: My first dyno== SAD =( (BBA)
somethings really weird here.
the HP and TQ both have a hickup at 4000rpm, while that isn't overly strange, what happens after it is strange.
notice how both HP and TQ are noticeably higher than before (as in the lines don't match up with the general direction before 4000rpm). something happened and all the sudden its making more power.
the hickup and waviness are most likely Ignition related (bad plug/wire, timing off or worn distributor gear?).
as far as the power or lack thereof, your going to have to hook up a scan tool and see what the air fuel ratio is doing.
oh hey, didn't I read somewhere just recently about the double wall tubing collapsing in the exhaust sometimes and restricting the inside while the outside looks normal????
the HP and TQ both have a hickup at 4000rpm, while that isn't overly strange, what happens after it is strange.
notice how both HP and TQ are noticeably higher than before (as in the lines don't match up with the general direction before 4000rpm). something happened and all the sudden its making more power.
the hickup and waviness are most likely Ignition related (bad plug/wire, timing off or worn distributor gear?).
as far as the power or lack thereof, your going to have to hook up a scan tool and see what the air fuel ratio is doing.
oh hey, didn't I read somewhere just recently about the double wall tubing collapsing in the exhaust sometimes and restricting the inside while the outside looks normal????