Drag Racing a Vette
Thread Starter
Intermediate
Joined: Jan 2011
Posts: 33
Likes: 0
Drag Racing a Vette
Does anyone here drag race their 73'-76' Vette? I want to run a 9 x 28 slick and run low 13 to high 12 second 1/4 mile times. Would like to hear on shocks, traction devices, or problems you guys have run into.
Melting Slicks
Joined: May 2005
Posts: 2,209
Likes: 12
From: Montgomery Alabama
Cruise-In VII Veteran
St. Jude Donor '06
Get a set of old worn out shocks for the front or some nice 90/10 drag shocks. Take loose the sway bars.
Make sure you have solid u-joints on teh half shafts and drive shaft. Install drive shaft/half shaft loops and a scatter shield.
I have issues with traction in first gear with street tires so I start in second. I run low 13 second times, and wheelspin is sitll an issue with me.
I busted an axle a couple years ago and had 30 spline inner axles and 12 bolt guts put in the differential last year and put 31 spline outer axles and 3" half shafts in the car this year. I need to get my scatter shield and my half shaft loops installed before I will try the drag slicks or drag radials.
Right now, with the street tires, I don't feel too unsafe. Traction is my main issue (and my shifting).
Have fun!
The best and cheapest solution to drag racing a Vette is a 9" Ford rearend with a ladder bar set-up. For what I spent on the Vette differential parts alone, I could have a Ford diff that handles 1200 HP. My Vette diff is only good for about 500 HP.
Make sure you have solid u-joints on teh half shafts and drive shaft. Install drive shaft/half shaft loops and a scatter shield.
I have issues with traction in first gear with street tires so I start in second. I run low 13 second times, and wheelspin is sitll an issue with me.
I busted an axle a couple years ago and had 30 spline inner axles and 12 bolt guts put in the differential last year and put 31 spline outer axles and 3" half shafts in the car this year. I need to get my scatter shield and my half shaft loops installed before I will try the drag slicks or drag radials.
Right now, with the street tires, I don't feel too unsafe. Traction is my main issue (and my shifting).
Have fun!
The best and cheapest solution to drag racing a Vette is a 9" Ford rearend with a ladder bar set-up. For what I spent on the Vette differential parts alone, I could have a Ford diff that handles 1200 HP. My Vette diff is only good for about 500 HP.
Instructor
Joined: Feb 2007
Posts: 138
Likes: 2
From: Buies Creek NC
I used ladder bars in my '81 and had to remove the rear chassis cross bar to do so. I ended up doing a full 2x3 frame under it. I would 4-link it with the kit from Autofab and put in a 9" Ford rear. This kit retains all the stock frame. You'll have to modify the battery compartments to make room for the diff to travel.
Racer
Joined: Feb 2009
Posts: 273
Likes: 11
From: Algona, WA
Is this a manual or auto? Auto is much easier to keep together. Manuael will tear hell outta everthing. 1 peice at a time.
The tires you choose, whether bias or radials will depend on transmision type. Manuel trans-bias slicks. auto trans-drag radials. A lower H/P SBC will like a 26" tire, More H/P SBC or BBC a 28" tire works better.
I run the stock 3.08 rear in my car with auto. Still has the origianal 17 spline yokes, and have over a 100+ pass's with out breaking.... 700+H/P
runs high 9.s low 10.s on pump gas and street tires.
A stick car would be lucky to make 2 passes.
Soooh....Whatcha you running?
The tires you choose, whether bias or radials will depend on transmision type. Manuel trans-bias slicks. auto trans-drag radials. A lower H/P SBC will like a 26" tire, More H/P SBC or BBC a 28" tire works better.
I run the stock 3.08 rear in my car with auto. Still has the origianal 17 spline yokes, and have over a 100+ pass's with out breaking.... 700+H/P
runs high 9.s low 10.s on pump gas and street tires.
A stick car would be lucky to make 2 passes.
Soooh....Whatcha you running?
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
I used ladder bars in my '81 and had to remove the rear chassis cross bar to do so. I ended up doing a full 2x3 frame under it. I would 4-link it with the kit from Autofab and put in a 9" Ford rear. This kit retains all the stock frame. You'll have to modify the battery compartments to make room for the diff to travel.
Instructor
Joined: Feb 2007
Posts: 138
Likes: 2
From: Buies Creek NC
You're right. For what the OP is trying to do, good solid U-joints all the way is a good starting point. But we all know the itch for more speed. And on these cars, more speed = broken rears. Someone mentioned ladder bars and I was mearly telling of my experience with them. It is fairly easy to install a 4-link system in a C3 and retain the stock frame. My '81 has ladder bars and a Dana 60. It runs mid 8s in the 1/4 so I definately need good parts.
Drifting
Joined: Aug 2005
Posts: 1,682
Likes: 3
From: League City TX
You'll have all the traction you need with stock suspension.
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Thread Starter
Intermediate
Joined: Jan 2011
Posts: 33
Likes: 0
My car is a 74' with a 383 and TH 400 with a stock converter. The engine has an Eagle cast crank, SIR rods, and hyper flat top pistons. The heads are 487Xs I had laying around, put 2.05/1.60 valves in them along with screw-in-studs and guide plates. I'm running Scorpion roller rockers. Also bowl hogged them, narrowed guide bosses,and opened pushrod pinch area. Cam is a Comp 268XE flat hydraulic. Performer RPM manifold with 750 DP. The suspension is completely stock. What about rear shocks? Any recommendations? Find adjustables? Where do you find half shaft loops? And what exactly is this rearend if you can put 12-bolt parts in it? Sorry I've been working on Camaros too long. Anything help in the spring department. Thanks for your replies.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Along with your stock converter, you probably have 3.08 gears. Those are the 2 biggest problems you have in getting to near 13.00, with a fairly mild engine. You should make a few passes on a track the way the car is, on street tires. If you can run at least 102 / 103 mph, you should get the ET you're looking for, after you improve the launch. Something like 2,800 rpm stall and 3.73 gears would do it, even on street tires, but more consistently and quicker on drag radials.
Racer
Joined: Nov 2008
Posts: 491
Likes: 0
From: Myrtle Beach South Carolina
There's a whole section on Drag Racing in this forum:
http://forums.corvetteforum.com/drag-racing-90/
FYI...
http://forums.corvetteforum.com/drag-racing-90/
FYI...
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
3.08 rear - F41 Slalom suspension - M21 - 27" tall 285/40/18" Toyo tyres. Up front 489 cu in/528 hp/565 ft/lbs torque = easy best 13.06 @ 101 mph at first drag outing last year - strip was old WW2 concrete runway with very poor traction (theres better grip out there on the street!) 
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Stock suspension will work perfect for what you want to do..... You really need to spend $$ on the half shafts(or atleast solid u joints in all 3 shafts)....
You really don't even need anything other then stock shocks.....Only thing you MAY consider is if youre rear spring is wore out....if so, change it now. You want to try to somewhat limit your rear squat, if the spring is shot or the rear shocks are shot, thats gonna cause it to squat which in turn causes broken u joints/shafts/side yokes etc etc.....
FWIW I went 10.90s with a bone stock suspension other then cheap KYB gas adjust shocks all the way around and a 20 year old TRW 340lb rear spring..... Even had the front sway bar still hooked up....It went 1.57 60's like that.....This was on an original 148k mile IRS with 3.08 gears....I did have good half shafts and all solid u joints though...
Vettes with IRS hook up awesome....(on GOOD drag radials anyway...)
You really don't even need anything other then stock shocks.....Only thing you MAY consider is if youre rear spring is wore out....if so, change it now. You want to try to somewhat limit your rear squat, if the spring is shot or the rear shocks are shot, thats gonna cause it to squat which in turn causes broken u joints/shafts/side yokes etc etc.....
FWIW I went 10.90s with a bone stock suspension other then cheap KYB gas adjust shocks all the way around and a 20 year old TRW 340lb rear spring..... Even had the front sway bar still hooked up....It went 1.57 60's like that.....This was on an original 148k mile IRS with 3.08 gears....I did have good half shafts and all solid u joints though...
Vettes with IRS hook up awesome....(on GOOD drag radials anyway...)
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
Stock suspension will work perfect for what you want to do..... You really need to spend $$ on the half shafts(or atleast solid u joints in all 3 shafts)....
You really don't even need anything other then stock shocks.....Only thing you MAY consider is if youre rear spring is wore out....if so, change it now. You want to try to somewhat limit your rear squat, if the spring is shot or the rear shocks are shot, thats gonna cause it to squat which in turn causes broken u joints/shafts/side yokes etc etc.....
FWIW I went 10.90s with a bone stock suspension other then cheap KYB gas adjust shocks all the way around and a 20 year old TRW 340lb rear spring..... Even had the front sway bar still hooked up....It went 1.57 60's like that.....This was on an original 148k mile IRS with 3.08 gears....I did have good half shafts and all solid u joints though...
Vettes with IRS hook up awesome....(on GOOD drag radials anyway...)
You really don't even need anything other then stock shocks.....Only thing you MAY consider is if youre rear spring is wore out....if so, change it now. You want to try to somewhat limit your rear squat, if the spring is shot or the rear shocks are shot, thats gonna cause it to squat which in turn causes broken u joints/shafts/side yokes etc etc.....
FWIW I went 10.90s with a bone stock suspension other then cheap KYB gas adjust shocks all the way around and a 20 year old TRW 340lb rear spring..... Even had the front sway bar still hooked up....It went 1.57 60's like that.....This was on an original 148k mile IRS with 3.08 gears....I did have good half shafts and all solid u joints though...
Vettes with IRS hook up awesome....(on GOOD drag radials anyway...)
A good point that too many overlook!
F41 suspension/489cu in/M21/3.08/18" Toyo's/minimal rear end squat fair amount of front end lift (good weight transfer?)
At rest
'Feathering' off line
A bit 'further out'
Easy but slippery 13.08 @ 101 mph
Thread Starter
Intermediate
Joined: Jan 2011
Posts: 33
Likes: 0
Ok, now I'm starting to get the picture. Good shocks, stiffen the rear suspension to prevent squat. I'm going to take out the rear end to clean underneath the back of the car so that would be a good time to change all the u-joints.
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
If me wanting to stay GM, would go with an older 2500 lb Vega, nicely built small block and Currie 9" solid axle. Will show it's tail lights to a 3400 lb IRS car in the quarter all day long.
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
If you look at my photos you can see where the rear wheels were spinning in the upper speed range.