Drag Radial Consistent 60ft Times
#1
Pro
Thread Starter
Drag Radial Consistent 60ft Times
How consistent are your 60ft times with drag radials.
I am chasing 60ft times on my 76 Vette with MT Drag Radials.
Here's how my day at the track usually goes:
1st pass 1.65 to 1.67 60ft
2nd pass 1.65 to 1.67 60 ft
3rd pass 1.71 to 1.73 60 ft
4th pass 1.68 to 1.71 60 ft
Last weekend my fifth pass was 1.601 60ft.
My setup:
468 BBC
520 hp at flywheel.
350 Turbo Auto Tranny
3:36 gears
3500 stall
16-psi Drag Radials
35-psi Front Tires
Front and Rear Swaybars still hooked up
Regular street shocks front and rear
I am trying to figure out if this is typical consistency for drag radials, or if I have other issues going on.
Here's my process at the line:
1. Drive through water box
2. Burnout - 1ft on brake and 1ft on gas, Start in 1st gear, at 5000 rpm shift into second, as tires heat up and I feel the car trying to move car forward I ease off the brake and shoot forward.
3. Idle up to the line and light the first bulb.
4. 1ft on brake and 1ft on gas, raise rpm to 2200. Ease off brake, move forward, light second light
5. When I get the green light (3rd Yellow Light) - WOT and release brake at the same time.
Tires never feel like they are slipping when I launch. Engine does not bog when I take off, it leaves crisp and feels strong.
Rambling on now, any tips, suggestions, ways to figure out if its my converter, tranny, differential, engine, etc.
Roger
I am chasing 60ft times on my 76 Vette with MT Drag Radials.
Here's how my day at the track usually goes:
1st pass 1.65 to 1.67 60ft
2nd pass 1.65 to 1.67 60 ft
3rd pass 1.71 to 1.73 60 ft
4th pass 1.68 to 1.71 60 ft
Last weekend my fifth pass was 1.601 60ft.
My setup:
468 BBC
520 hp at flywheel.
350 Turbo Auto Tranny
3:36 gears
3500 stall
16-psi Drag Radials
35-psi Front Tires
Front and Rear Swaybars still hooked up
Regular street shocks front and rear
I am trying to figure out if this is typical consistency for drag radials, or if I have other issues going on.
Here's my process at the line:
1. Drive through water box
2. Burnout - 1ft on brake and 1ft on gas, Start in 1st gear, at 5000 rpm shift into second, as tires heat up and I feel the car trying to move car forward I ease off the brake and shoot forward.
3. Idle up to the line and light the first bulb.
4. 1ft on brake and 1ft on gas, raise rpm to 2200. Ease off brake, move forward, light second light
5. When I get the green light (3rd Yellow Light) - WOT and release brake at the same time.
Tires never feel like they are slipping when I launch. Engine does not bog when I take off, it leaves crisp and feels strong.
Rambling on now, any tips, suggestions, ways to figure out if its my converter, tranny, differential, engine, etc.
Roger
#2
Here is something to think about. You need to stage the car exactly the same spot every time. East-West placement is just as important as North-South. Most track have a crown and rollout will change inside the grove vs outside.
I would also have you try stopping before turning on the pre-stage. Bring the car up to 2200 as stage as you do normally. This should insure that the supension is loading the same way each run.
I would also have you try stopping before turning on the pre-stage. Bring the car up to 2200 as stage as you do normally. This should insure that the supension is loading the same way each run.
Last edited by kazman; 05-09-2013 at 06:02 PM.
#3
Race Director
1st thing I can't understand is why you are only 60' in 1.65 ??
I have a 2005 with a few bolt on's 3.15 rear and an FTI 2800 converter, & with $hitty Nitto 305/35x18" Drag Radials I will 60 in 1.62 - 1.65 about 75% of the time... (I spin the other 25% because of the New 2800 converter... when I had the stock converter my 60' was 1.88 1.90 with the Nittos...
I just bought a set of MT (same size) and I think my 60' will STILL be 1.60 - 1.63 but it will do it ALL THE TIME on the MT...
As mentioned above be sure when you stage, ...light the TOP bulb.. and "creep" forward VERRRRRRY slowly until you light the bottom bulb.. just as soon as it starts to flicker STOP or go forward 1" more..
I "personally" would do this at an "idle" you have more control of the car.. THEN when you are staged bring up the RPM to 2200...
Give this a try...
I have a 2005 with a few bolt on's 3.15 rear and an FTI 2800 converter, & with $hitty Nitto 305/35x18" Drag Radials I will 60 in 1.62 - 1.65 about 75% of the time... (I spin the other 25% because of the New 2800 converter... when I had the stock converter my 60' was 1.88 1.90 with the Nittos...
I just bought a set of MT (same size) and I think my 60' will STILL be 1.60 - 1.63 but it will do it ALL THE TIME on the MT...
As mentioned above be sure when you stage, ...light the TOP bulb.. and "creep" forward VERRRRRRY slowly until you light the bottom bulb.. just as soon as it starts to flicker STOP or go forward 1" more..
I "personally" would do this at an "idle" you have more control of the car.. THEN when you are staged bring up the RPM to 2200...
Give this a try...
#4
Pro
Thread Starter
Kazman,
I do try and lineup in the "groove" east-west on track. I usually try and line up behind the guy at line, thinking he's in the right spot. Maybe he's not, he might be lost like me.
I'll try stopping before staging and see how that does. One more thing I can do for consistency, thanks.
Jpee,
Glad to hear your MT's drag radials are consistent. Just one more thing I can cross off my list of reasons for inconsistency.
I believe my 60fts are slow because of the 990 rectangular port heads I am using. They are bone stock (no porting or polishing). They have the reputation of not working well at low rpms. Down the road I plan to get better heads but for now that's what I have to work with.
I do have one 60ft at 1.601 and my best ever happened a couple weekends ago 1.599.
I'll try bringing up the rpms after staging and report back.
Thanks,
Roger
I do try and lineup in the "groove" east-west on track. I usually try and line up behind the guy at line, thinking he's in the right spot. Maybe he's not, he might be lost like me.
I'll try stopping before staging and see how that does. One more thing I can do for consistency, thanks.
Jpee,
Glad to hear your MT's drag radials are consistent. Just one more thing I can cross off my list of reasons for inconsistency.
I believe my 60fts are slow because of the 990 rectangular port heads I am using. They are bone stock (no porting or polishing). They have the reputation of not working well at low rpms. Down the road I plan to get better heads but for now that's what I have to work with.
I do have one 60ft at 1.601 and my best ever happened a couple weekends ago 1.599.
I'll try bringing up the rpms after staging and report back.
Thanks,
Roger
#5
Le Mans Master
My 60s are in the 1.5s on drag radials and they are usually very consistent. Usually within a couple of hundredths throughout the day. When my 60s vary more its usually because I screw up staging.
#6
#8
Race Director