1982 1/4 Mile Time
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From: Northern Kentucky
1982 1/4 Mile Time
For those interested in the gains from headers and dual exhaust over stock. I ran my 82 last night just to get a base before I start making additional mods. My time was 15.45 at 88.21 mph. I believe straight stock with stock exhaust is listed at 16.10 for the quarter mile.
Last edited by Tslayer66; Aug 4, 2018 at 09:48 AM.
Melting Slicks
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For those interested in the gains from headers and dual exhaust over stock. I ran my 82 last night just to get a base before I start making additional mods. My time was 15.45 at 88.21 mph. I believe straight stock with stock exhaust is listed at 16.10 for the quarter mile.
I have been as much as 1 sec difference Spring vs fall (Stock L48 78 corvette) (15.7-16.7) so I use this to determine a better base time.
http://www.dragtimes.com/da-density-...calculator.php
hopefully your location is in the database. But I did the same as you are thinking find out the performance changes (real life) after each mod. Please report back after each change. This is great real world feed back.
Le Mans Master
Joined: May 2002
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From: Lebanon Township New Jersey
So you ran a 15.45 compared to published data 16.10. I believe 6 tenths reduction is possible with headers and full duals compared to manifolds, 2 into 1, a cat and stock mufflers. My car picked up 4 tenths switching from manifolds to headers and stock type mufflers (full duals) to Magnaflows.
You should record the DA (density altitude) because that can make 2 or 3 tenths difference itself in August compared to October - depending on where you are located.
Cargotzmann beat me to it.
You should record the DA (density altitude) because that can make 2 or 3 tenths difference itself in August compared to October - depending on where you are located.
Cargotzmann beat me to it.
Last edited by BKbroiler; Aug 4, 2018 at 10:19 AM.
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From: Northern Kentucky
I guess it depends on where in the world you are and the DA on the day you went to the drag strip.
I have been as much as 1 sec difference Spring vs fall (Stock L48 78 corvette) (15.7-16.7) so I use this to determine a better base time.
http://www.dragtimes.com/da-density-...calculator.php
hopefully your location is in the database. But I did the same as you are thinking find out the performance changes (real life) after each mod. Please report back after each change. This is great real world feed back.
I have been as much as 1 sec difference Spring vs fall (Stock L48 78 corvette) (15.7-16.7) so I use this to determine a better base time.
http://www.dragtimes.com/da-density-...calculator.php
hopefully your location is in the database. But I did the same as you are thinking find out the performance changes (real life) after each mod. Please report back after each change. This is great real world feed back.
Density Altitude: 2083 feet
Relative Density: 94.05 %
Melting Slicks
Joined: Jun 2011
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Stock and Mildly Modified Naturally Aspirated Engines
15.078 @ 90.438 MPH
Extensively Modified Naturally Aspirated Engines
15.217 @ 89.667 MPH
Extensively Modified Supercharged and Turbocharged Engines
15.317 @ 88.977 MPH
Also your track is in the database. On the left select USA-OH-Edgewater Sports Park. Select the date & time of the run. Click get weather data (if your time slip doesn't have a DA already on it)
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From: Northern Kentucky
Using the link I get these numbers
Stock and Mildly Modified Naturally Aspirated Engines
15.078 @ 90.438 MPH
Extensively Modified Naturally Aspirated Engines
15.217 @ 89.667 MPH
Extensively Modified Supercharged and Turbocharged Engines
15.317 @ 88.977 MPH
Also your track is in the database. On the left select USA-OH-Edgewater Sports Park. Select the date & time of the run. Click get weather data (if your time slip doesn't have a DA already on it)
Stock and Mildly Modified Naturally Aspirated Engines
15.078 @ 90.438 MPH
Extensively Modified Naturally Aspirated Engines
15.217 @ 89.667 MPH
Extensively Modified Supercharged and Turbocharged Engines
15.317 @ 88.977 MPH
Also your track is in the database. On the left select USA-OH-Edgewater Sports Park. Select the date & time of the run. Click get weather data (if your time slip doesn't have a DA already on it)
Le Mans Master
Joined: May 2002
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From: Lebanon Township New Jersey
The Data is saying that if the DA was zero, your ET would be 15.07. The DA can be well below zero which would result in even better ETs. I've seen DA as low as -1500.
Safety Car
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Like mentioned above, the DA has a HUGE amount to do with your motor performance on any given day. The lower the DA the better your motor will run and the lower your ET should be given the same amount of traction. Test it again this fall and see the difference. Good luck with your 82 CFI. 
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Yes, i wont say that it throws me back in my seat but its definitely an incremental improvement. The car launches much better than stock. Now i want to continue on this path. My next part of the project is a performance CAM, aluminum heads and the renegade manifold. From investigating on the forum it seems its best to do all three of these at once?I definitely will need some suggestions on parts so I can start pricing this out. My long term goal is to get into the low 14s. or even high 13s would be nice for a street C3. Not sure this is possible with the CFI but sure others on here will let me know.
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St. Jude Donor '05
A set of AFR 180s, Trick Flow TFS 175s, a 256-264 type cam, Renegade intake and maybe a small converter ought to get you your goal whi9le make the CFI system happy without a lot of hassle.Always liked the way the Isky Mega cams ran...good torque but not such a stupid ramp you worry about it going flat.
Learned my lesson the hard way a few times with steep ramp FT cams. Its not worth the few lbs of torque
The 256 will have a smooth idle (but throaty) the 264 will have a slight lope to it. Nothing big but youll know it has a cam, CFI should be Ok with it.
Sure theres plenty of others but those work real well with mild 350s.
Unless you have one hell of a tall gear you may break into the 13s.
Learned my lesson the hard way a few times with steep ramp FT cams. Its not worth the few lbs of torque
The 256 will have a smooth idle (but throaty) the 264 will have a slight lope to it. Nothing big but youll know it has a cam, CFI should be Ok with it.
Sure theres plenty of others but those work real well with mild 350s.
Unless you have one hell of a tall gear you may break into the 13s.
Last edited by cv67; Aug 6, 2018 at 09:51 AM.
Le Mans Master
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From: columbia city in
I would not go too big on the heads ,180 cc and I would call crane on what cam plays well with the crossfire.i would also think about roller rockers. find some that will work under your valve covers or then you will need tall covers..doing everything at one time saves time and money.have fun and keep us posted on your progress.
Burning Brakes
Joined: Mar 2016
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Yes, i wont say that it throws me back in my seat but its definitely an incremental improvement. The car launches much better than stock. Now i want to continue on this path. My next part of the project is a performance CAM, aluminum heads and the renegade manifold. From investigating on the forum it seems its best to do all three of these at once?I definitely will need some suggestions on parts so I can start pricing this out. My long term goal is to get into the low 14s. or even high 13s would be nice for a street C3. Not sure this is possible with the CFI but sure others on here will let me know.
Example:
Pro-Filer 195cc heads (Jegs re-branded ones are $1,000 pair, probably can't find better flowing heads for the price).
Lunati 60103 (268) flat tappet cam
Renegade manifold (and whatever else you need on the induction side to support the heads and cam. I don't know much about the fuel injected C3's, but plenty on here do.)
That setup coupled with a .015 shim head gasket would give you roughly 9.5:1 compression ratio, still good enough idle vacuum to operate your headlights, power brakes, etc... and a solid 350+ hp, which should be enough to get you into the 13's (assuming you have an appropriate sized stall converter).
Definitely do it all at once! Sucks to pay for the same gaskets twice and do the same work twice!
If you have a bit more budget, go for a Howard's retro-roller cam to free up a bit more power and not have the hassle of a FT cam. If you have a smaller budget, stick with the FT cam and look for some Vortec heads (assuming they play nice with the Renegade manifold, search on here and see)
Last edited by mobird; Aug 6, 2018 at 12:27 PM.
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From: altered state
St. Jude Donor '05
Good point mentioning Crane, didnt they have a line that was specifically for those early EFI cars? 2032 or something like that? Less overlap keeps the CFI happy. Believe Crower made some also
Keep stock rockers if you can theres 0 advantage going with a roller rocker with those sized cams, keeping short valve covers are a plus.
Keep stock rockers if you can theres 0 advantage going with a roller rocker with those sized cams, keeping short valve covers are a plus.
Last edited by cv67; Aug 6, 2018 at 12:41 PM.
Burning Brakes
Joined: Mar 2016
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Good point mentioning Crane, didnt they have a line that was specifically for those early EFI cars? 2032 or something like that? Less overlap keeps the CFI happy. Believe Crower made some also
Keep stock rockers if you can theres 0 advantage going with a roller rocker with those sized cams, keeping short valve covers are a plus.
Keep stock rockers if you can theres 0 advantage going with a roller rocker with those sized cams, keeping short valve covers are a plus.
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From: Clymer PA
Tslayer66:
It's fun isn't it? That's over half a second faster. I think my '76 went like 15.90s at like 89MPH when I had the original motor in it. I think it's a blast to race it, make adjustments/modifications, race it again and try to beat your best time. Great work, now let's see if you can shave another .10 or so off of there.
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Tslayer66:
It's fun isn't it? That's over half a second faster. I think my '76 went like 15.90s at like 89MPH when I had the original motor in it. I think it's a blast to race it, make adjustments/modifications, race it again and try to beat your best time. Great work, now let's see if you can shave another .10 or so off of there.
A set of AFR 180s, Trick Flow TFS 175s, a 256-264 type cam, Renegade intake and maybe a small converter ought to get you your goal whi9le make the CFI system happy without a lot of hassle.Always liked the way the Isky Mega cams ran...good torque but not such a stupid ramp you worry about it going flat.
Learned my lesson the hard way a few times with steep ramp FT cams. Its not worth the few lbs of torque
The 256 will have a smooth idle (but throaty) the 264 will have a slight lope to it. Nothing big but youll know it has a cam, CFI should be Ok with it.
Sure theres plenty of others but those work real well with mild 350s.
Unless you have one hell of a tall gear you may break into the 13s.
Learned my lesson the hard way a few times with steep ramp FT cams. Its not worth the few lbs of torque
The 256 will have a smooth idle (but throaty) the 264 will have a slight lope to it. Nothing big but youll know it has a cam, CFI should be Ok with it.
Sure theres plenty of others but those work real well with mild 350s.
Unless you have one hell of a tall gear you may break into the 13s.
- Trick Flow DHC 175 Heads - https://www.summitracing.com/search/...ibanner=SREPD5
- Comp Cams Camshaft - https://www.summitracing.com/parts/cca-12-206-2
- Renegade Manifold - https://www.summitracing.com/parts/ems-msren-100
Let me know your ideas and I also hope to run it by Buccaneer as I know he has helped me in the past as well.
Keep in mind that I want to keep this street use first and race track second in priority. So being conservative is ok with me.
Appreciate your comments
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From: Clymer PA
That's why the track is awesome, modifications that don't give you the "seat of the pants feel" like you had imagined are proven to not have been a waste of time and money. Improvements in .10 of a second increments, without a run at the track/dyno, make you feel like you wasted your time. The time slips show you that it was a success (however great or small), a bunch of small things slowly become a big one. Keep up the good work!
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From: Northern Kentucky
terry82:
That's why the track is awesome, modifications that don't give you the "seat of the pants feel" like you had imagined are proven to not have been a waste of time and money. Improvements in .10 of a second increments, without a run at the track/dyno, make you feel like you wasted your time. The time slips show you that it was a success (however great or small), a bunch of small things slowly become a big one. Keep up the good work!
That's why the track is awesome, modifications that don't give you the "seat of the pants feel" like you had imagined are proven to not have been a waste of time and money. Improvements in .10 of a second increments, without a run at the track/dyno, make you feel like you wasted your time. The time slips show you that it was a success (however great or small), a bunch of small things slowly become a big one. Keep up the good work!