Yesterdays Dyno Test!
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Yesterdays Dyno Test!
I had my 68' dyno tested ad the "Dyno Day at Mike Norris Motorsports"!
I gained the horsepower back that I lost after fixing my gas pedal problem. For those who haven't read my previous posts - I had the car initially dynoed at 324.3 RWHP a couple of weeks back. After that dyno run - I found out that I was running only 70% throttle. I fixed the problem with the gas pedal linkage and had the car re-dynoed a couple of days later. The power dropped to 300 RWHP :eek: with full throttle!! Since then I changed my plug wires, plugs and gapping. I gained the lost power back. This time I dynoed at 325.3 RWHP with full throttle!. There was a lot of black smoke coming out at certain RPMs... Some MAJOR tuning and a carb change needs to be done and I'm sure that it will be possible to free up at least another 30 - 40 HP. I will also remove the inserts in my exhaust which should add another 5 - 10 HP... I hope that re-curving the distributor will make some change too!!!
Here is the dyno sheet:
:cheers:
Olivier
I gained the horsepower back that I lost after fixing my gas pedal problem. For those who haven't read my previous posts - I had the car initially dynoed at 324.3 RWHP a couple of weeks back. After that dyno run - I found out that I was running only 70% throttle. I fixed the problem with the gas pedal linkage and had the car re-dynoed a couple of days later. The power dropped to 300 RWHP :eek: with full throttle!! Since then I changed my plug wires, plugs and gapping. I gained the lost power back. This time I dynoed at 325.3 RWHP with full throttle!. There was a lot of black smoke coming out at certain RPMs... Some MAJOR tuning and a carb change needs to be done and I'm sure that it will be possible to free up at least another 30 - 40 HP. I will also remove the inserts in my exhaust which should add another 5 - 10 HP... I hope that re-curving the distributor will make some change too!!!
Here is the dyno sheet:
:cheers:
Olivier
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Yesterdays Dyno Test! (GrandSportC3)
I think I have a similar problem. I street raced a friend with a 15 second flat CRX (he pulled away from me...very embarrassing) and when I was backing down I found that when I pulled my foot slowly of the gas from WOT the car actually accelerated faster at what seemed to be about 90% throttle. I am guessing that it's the vacuum advance feed. backing off the throttle a bit could be adding more advance to the distributor. I'll need to check this with a vacuum gauge attached to the vacuum advance hose the next time I go out for some WOTs.
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Rockn-Roll)
I think I have a similar problem. I street raced a friend with a 15 second flat CRX (he pulled away from me...very embarrassing) and when I was backing down I found that when I pulled my foot slowly of the gas from WOT the car actually accelerated faster at what seemed to be about 90% throttle. I am guessing that it's the vacuum advance feed. backing off the throttle a bit could be adding more advance to the distributor. I'll need to check this with a vacuum gauge attached to the vacuum advance hose the next time I go out for some WOTs.
:cheers:
Olivier
[Modified by GrandSportC3, 1:54 PM 7/21/2002]
Melting Slicks
Joined: Aug 2000
Posts: 2,900
Likes: 2
From: Green Cove Springs FL
Re: Yesterdays Dyno Test! (GrandSportC3)
Thanks for taking me for a ride yesterday! Those sidepipes are awesome, but the burn on my leg isn't. :reddevil
Glad to see you made it back okay.
Glad to see you made it back okay.
Melting Slicks
Joined: Aug 1999
Posts: 3,123
Likes: 13
From: Hollywood, Florida
Re: Yesterdays Dyno Test! (GrandSportC3)
Oliver,
I'm glad to hear that you got back the 20 or so lost HP!!! I think once Lars recurves youd dist. you will find some more, along with the fuel system changes you want to try.
I hope he can find me some more HP when he is here and does my distributor :cheers:
I'm glad to hear that you got back the 20 or so lost HP!!! I think once Lars recurves youd dist. you will find some more, along with the fuel system changes you want to try.
I hope he can find me some more HP when he is here and does my distributor :cheers:
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Corey 68)
Olivier
I agree with you you still have some power tied up in that car. It's just a matter of fine tuning everything. :cheers:
I agree with you you still have some power tied up in that car. It's just a matter of fine tuning everything. :cheers:
:cheers:
Olivier
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (FroDaddy)
Thanks for taking me for a ride yesterday! Those sidepipes are awesome, but the burn on my leg isn't. :reddevil
Glad to see you made it back okay.
Glad to see you made it back okay.
:cheers:
Olivier
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Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (shoptek)
Oliver,
I'm glad to hear that you got back the 20 or so lost HP!!! I think once Lars recurves youd dist. you will find some more, along with the fuel system changes you want to try.
I hope he can find me some more HP when he is here and does my distributor :cheers:
I'm glad to hear that you got back the 20 or so lost HP!!! I think once Lars recurves youd dist. you will find some more, along with the fuel system changes you want to try.
I hope he can find me some more HP when he is here and does my distributor :cheers:
:cheers:
Olivier
Burning Brakes
Joined: Jul 1999
Posts: 1,013
Likes: 0
From: Austin TX
Re: Yesterdays Dyno Test! (GrandSportC3)
Glad to hear you got your power back, I feel you have more in there once the carb in tuned right, check your plugs again b4 you go in case they get fouled out.
Race Director
Joined: Oct 2000
Posts: 15,120
Likes: 79
From: central FL, near the beach.
Re: Yesterdays Dyno Test! (GrandSportC3)
if total timing is good now, the recurve will not change peak power, just bring in more power at lower rpm.
funny how one earlier test showed too lean, now you complain of black smoke. My cars have o2 sensors to sort this stuff out.
funny how one earlier test showed too lean, now you complain of black smoke. My cars have o2 sensors to sort this stuff out.
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (StingrayRacing)
Glad to hear you got your power back, I feel you have more in there once the carb in tuned right, check your plugs again b4 you go in case they get fouled out.
:cheers:
Olivier
Thread Starter
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Joined: Jul 2001
Posts: 182,997
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Matt Gruber)
if total timing is good now, the recurve will not change peak power, just bring in more power at lower rpm.
funny how one earlier test showed too lean, now you complain of black smoke. My cars have o2 sensors to sort this stuff out.
funny how one earlier test showed too lean, now you complain of black smoke. My cars have o2 sensors to sort this stuff out.
I would like to install a o2 sensor but I don't want to drill a hole in my pipes to mount it... After changing the carb - I'm thinking in having the car dyno-tuned... I want to get a A/F of 12.9 - 13.0 on the dyno. One of the dyno guys told me that on the track you usually run leaner because of the increased air flow...
:cheers:
Olivier
[Modified by GrandSportC3, 11:17 AM 7/22/2002]
Race Director
Joined: Oct 2000
Posts: 15,120
Likes: 79
From: central FL, near the beach.
Re: Yesterdays Dyno Test! (GrandSportC3)
i picked up a used set of headers for $35 and drilled 8 holes for the sensors. it is not that big of a deal.
after tuning(on the street, not the dyno), put the pretty set back on.
No need to change carbs if you do this, just dial in the one you have..
Othewise it is expensive guessing; dyno $$ for every combo.
good luck :cheers:
[Modified by Matt Gruber, 1:42 PM 7/22/2002]
after tuning(on the street, not the dyno), put the pretty set back on.
No need to change carbs if you do this, just dial in the one you have..
Othewise it is expensive guessing; dyno $$ for every combo.
good luck :cheers:
[Modified by Matt Gruber, 1:42 PM 7/22/2002]
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Matt Gruber)
i picked up a used set of headers for $35 and drilled 8 holes for the sensors. it is not that big of a deal.
after tuning(on the street, not the dyno), put the pretty set back on.
No need to change carbs if you do this, just dial in the one you have..
Othewise it is expensive guessing; dyno $$ for every combo.
good luck :cheers:
after tuning(on the street, not the dyno), put the pretty set back on.
No need to change carbs if you do this, just dial in the one you have..
Othewise it is expensive guessing; dyno $$ for every combo.
good luck :cheers:
:cheers:
Olivier
Drifting
Joined: Dec 1999
Posts: 1,462
Likes: 1
From: Reno nevada
Re: Yesterdays Dyno Test! (GrandSportC3)
What kind of a cam and heads do you have? I was wondering about why your profile lists 383/465 hp and the dyno runs indicate @ 400 at the crank.
I can see advantages to vacuum seconds. I have always had a double pumper on mine and I don't believe that it's any faster than an equivolent CFM Vac. carb because I tried a Edelbrock 750 for a short period of time. Both carbs were setup nearly the best posible. gkull had the Edel. sitting around so we installed it.
I can see advantages to vacuum seconds. I have always had a double pumper on mine and I don't believe that it's any faster than an equivolent CFM Vac. carb because I tried a Edelbrock 750 for a short period of time. Both carbs were setup nearly the best posible. gkull had the Edel. sitting around so we installed it.
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Lt1er)
What kind of a cam and heads do you have? I was wondering about why your profile lists 383/465 hp and the dyno runs indicate @ 400 at the crank.
I can see advantages to vacuum seconds. I have always had a double pumper on mine and I don't believe that it's any faster than an equivolent CFM Vac. carb because I tried a Edelbrock 750 for a short period of time. Both carbs were setup nearly the best posible. gkull had the Edel. sitting around so we installed it.
I can see advantages to vacuum seconds. I have always had a double pumper on mine and I don't believe that it's any faster than an equivolent CFM Vac. carb because I tried a Edelbrock 750 for a short period of time. Both carbs were setup nearly the best posible. gkull had the Edel. sitting around so we installed it.
238/248 degrees @ .050, .525/.540 lift
The heads are DART IRON EAGLE with 215 cc intake runners - ported (probably only stage 1 porting). The heads have bronze guides, 1.480 COMP dual springs, LUNATI Roller Rockers.... BTW- The engine is a 383 with steel crank, 9.8:1 CR. I had somebody input the specs of the engine in a desktop dyno and it came up with 477 HP.... Somthing is wrong....
I have heared that mech. secondaries carbs are better for single plane intakes but I don't know.
:cheers:
Olivier
[Modified by GrandSportC3, 2:38 PM 7/22/2002]
Drifting
Joined: Dec 1999
Posts: 1,462
Likes: 1
From: Reno nevada
Re: Yesterdays Dyno Test! (GrandSportC3)
We both have about the same type of cam. I have 1.6 CC roller tips and you have more cubes and better heads. Heres my cam. With Crane cams you need to match the compression to the cam so I have about 10.5 with very ported 186 casting 2.02/1.6
1. PowerMax Mechanical Lifter Camshafts for Non-Emissions Controlled Vehicles
Application Series & Grind Number
Fair idle, moderate performance usage, good mid-range HP, bracket racing, 3400-3800 cruise RPM, 10.0 to 11.5 compression ratio advised. Basic RPM 3000-6500 PowerMax F-278-2
replacing:
CC-278-2
Cam Specifications
Degrees Duration 238/248 @ .050 Int./Exh. Degrees Advertised Duration 278/288 Int./Exh. 114 Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. .480/.500 Gross Lift Int./Exh. with 1.5 lifters
Cam events
10 48
63 5
1. PowerMax Mechanical Lifter Camshafts for Non-Emissions Controlled Vehicles
Application Series & Grind Number
Fair idle, moderate performance usage, good mid-range HP, bracket racing, 3400-3800 cruise RPM, 10.0 to 11.5 compression ratio advised. Basic RPM 3000-6500 PowerMax F-278-2
replacing:
CC-278-2
Cam Specifications
Degrees Duration 238/248 @ .050 Int./Exh. Degrees Advertised Duration 278/288 Int./Exh. 114 Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. .480/.500 Gross Lift Int./Exh. with 1.5 lifters
Cam events
10 48
63 5
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Yesterdays Dyno Test! (Lt1er)
We both have about the same type of cam. I have 1.6 CC roller tips and you have more cubes and better heads. Heres my cam. With Crane cams you need to match the compression to the cam so I have about 10.5 with very ported 186 casting 2.02/1.6
1. PowerMax Mechanical Lifter Camshafts for Non-Emissions Controlled Vehicles
Application Series & Grind Number
Fair idle, moderate performance usage, good mid-range HP, bracket racing, 3400-3800 cruise RPM, 10.0 to 11.5 compression ratio advised. Basic RPM 3000-6500 PowerMax F-278-2
replacing:
CC-278-2
Cam Specifications
Degrees Duration 238/248 @ .050 Int./Exh. Degrees Advertised Duration 278/288 Int./Exh. 114 Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. .480/.500 Gross Lift Int./Exh. with 1.5 lifters
Cam events
10 48
63 5
1. PowerMax Mechanical Lifter Camshafts for Non-Emissions Controlled Vehicles
Application Series & Grind Number
Fair idle, moderate performance usage, good mid-range HP, bracket racing, 3400-3800 cruise RPM, 10.0 to 11.5 compression ratio advised. Basic RPM 3000-6500 PowerMax F-278-2
replacing:
CC-278-2
Cam Specifications
Degrees Duration 238/248 @ .050 Int./Exh. Degrees Advertised Duration 278/288 Int./Exh. 114 Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. .480/.500 Gross Lift Int./Exh. with 1.5 lifters
Cam events
10 48
63 5
:cheers:
Olivier