Should I being going faster

Bonzo · Dec 24, 2006

This year I took my 67 Coupe to the track.
It is a 289 with C4 3 speed Auto with the following mods.

Petronix Ignition
Flame Throer Coil
Road Demon 625 cfm
K&N X Stream Air Filter
Intake Manifold Power Plus
Cam Chet Herbert Hydraulic Cam RPM Range 1200-6000 - Advertised Duration 275/285 - Duration @.050:215/225 - Lift .475/.500 - Lobe Center; 112c
Cloydes True Rollers (Rhoades Lifters)
New conrod Bearings
Main Bearings
Headers
Re Cored Radiator
Quick Shift
Traction Bars
Front Sway Bar 1 1/4"

My best time has been:-
Run8
Tree 0.400
Reaction 0.918
60 2.719
330 7.354
MPH1 67.06
660 11.033
990 14.095
MPH2 85.2
ET1320 16.825

Manual shifting the Auto around 5,000 rpm

Should I run faster on the 1/4 mile. Whilst I am a novice from the reading on the forum I feel I should go quicker than I have been.

It would be useful to know if the car is capable of more and I should practice my technique or add more go faster bits.

Any advise greatly received.

Tony

BullittStangV8 · Dec 24, 2006

I think you should be running faster then 16.8 in the 1/4..Your 60 foot time is pretty high. You want that down around 2.1 or faster on street tires. If you mention what your launch technique is, when/if your wheel spin occurs, gearing, trap speed is, it would be easier to guess whats going on.

classic boost · Dec 24, 2006

you didn't say what size tire you have, but you really need to work on your 60ft time.

Eyeless_Seven · Dec 24, 2006

Are you carrying alot of weight in the trunk? Spare, toolbox...?

rbohm · Dec 24, 2006

Bonzo said:
This year I took my 67 Coupe to the track.
It is a 289 with C4 3 speed Auto with the following mods.

Petronix Ignition
Flame Throer Coil
Road Demon 625 cfm
K&N X Stream Air Filter
Intake Manifold Power Plus
Cam Chet Herbert Hydraulic Cam RPM Range 1200-6000 - Advertised Duration 275/285 - Duration @.050:215/225 - Lift .475/.500 - Lobe Center; 112c
Cloydes True Rollers (Rhoades Lifters)
New conrod Bearings
Main Bearings
Headers
Re Cored Radiator
Quick Shift
Traction Bars
Front Sway Bar 1 1/4"

My best time has been:-
Run8
Tree 0.400
Reaction 0.918
60 2.719
330 7.354
MPH1 67.06
660 11.033
990 14.095
MPH2 85.2
ET1320 16.825

Manual shifting the Auto around 5,000 rpm

Should I run faster on the 1/4 mile. Whilst I am a novice from the reading on the forum I feel I should go quicker than I have been.

It would be useful to know if the car is capable of more and I should practice my technique or add more go faster bits.

Any advise greatly received.

Tony

this car should be running in the mid 13sec bracket imo. next time you go to the strip disconnect the front sway bar, remove one end link to do this as that is all you need to do. that should help your 60 times measurably. your 60ft times should be in the 1.9-2.0 range on street tires, and in the 1.8-1.9 range on drag tires.

second, STOP SLEEPING AT THE LIGHT!! with a .918 reaction time you should call yourself rip van winkle you need to be leaving on the last yellow rather than wait for the green light. your reaction times should be in the .401-.450 range by the way, though geiing into the low .500 range isnt bad.

you dont mention what stall speed converter you are running, but it should be in the 2500 rpm stall spped range.

also what gear are you running? swapping from something like a 2.80 gear to a 3.5 will shave about .3 secs off your et, and swapping to a 3.89 can make a .5 sec difference.

as for driving technique, you should be leaving the line with the engine rpm around 2000-2500 rpm, and shifting at around 5500-6000 rpm. shifting at 5000 leaves power on the table rather than actually using. by the way, dont be afraid to try shifting at 6500 either as you might find the car goes quicker, course it might not also. you want to leave hard enough to spin the tires for a few feet, about 5-10ft at most, and leave your foot planted on the floor as long as you have traction(ok blatantly obvious i know, but some people still dont get that).

brianj5600 · Dec 24, 2006

At only 85 mph it won't run 13s. There is something wrong the motor or you tune.

ForceFed70 · Dec 24, 2006

brianj5600 said:
At only 85 mph it won't run 13s. There is something wrong the motor or you tune.

Agreed!

Even with a good 60ft and RT, this is still a 15sec car. From the mods you've listed, I would expect low 14s.

Max Power · Dec 24, 2006

13s is a major stretch with stock heads. Also, if I am not mistaken, even though you are sleeping at the light, the timer does not start until you trip the light, correct? Somebody correct me if I am wrong.

You are running slow, but don't expect 13, and 14s will be difficult with a car set up in street trim.

ga289stocker · Dec 24, 2006

Yeah your combo is for sure good for 14's. I have a similar combo and last year my first pass was a 16.7 @88mph. I forgot to disconnected my vaccum advance and air down my tires some. I ended that night w/ a15.45 @91+ on a 2.6 60" time on street radials. From there the only engine mod I made was making sure my carb was getting WOT which it wasn't. I put in adjustable rear shocks, spring clamps and a electic fan the next time out and went 14.56 @96+ w/ a 2.3 60". I had bad wheelhop don't know if that's a issue for you but a good set up supsension can do wonders. I still have the stock heads on my car now and the motor won't turn past 5400 rpm but it runs high 13's last time to track in Nov. w/ some ram air , battery relocate and some drag radials...which brings up tires. They will make or break you. I do think something may be amiss w/ your 85mph trap speed though. It really should be in the mid 90's range i would think w/ the parts you have listed. Keep at it though it's great seeing your hard work pay off w/ lower et's....

57fairlane · Dec 25, 2006

Like it has been stated, the 60ft is killing you. 2.0-2.1 60ft on street tires is entirely plausible. I pulled a 2.16 on 235/60/15 radial t/as.

Just through the 1/8 . . . the mph is there to run 10.1-10.2s which is in the 15s.
But you do need to get the car tuned. Untuned my car made 230rwhp with a c4, 3500 stall, 3.55s, ported windsor jr. alums, custom jay allen cam, 670 sa on a pp air-gap knockoff.

It went 9.2s at 75. So I would imagine the car is making around 190rwhp or so.

FYI, it ended up being the timing was locked out on my car. Cut off a rib under the rotor and the next pull it put down 250rwhp. It eventually made 268rwhp . . . trapped 87 in the 1/8.

67Dylan · Dec 25, 2006

Max Power said:
13s is a major stretch with stock heads. Also, if I am not mistaken, even though you are sleeping at the light, the timer does not start until you trip the light, correct? Somebody correct me if I am wrong.

You are running slow, but don't expect 13, and 14s will be difficult with a car set up in street trim.

You are correct sir; RT has no effect on ET, only when racing the driver in the next lane does it come into play.

IMO, sticky tires, gear change (assuming you have stock gears which is hindering you), and getting all your current power to the ground in the most profecient manner will drop your ET's considerably. Have fun at the track and work on your technique to improve your 60' as much as possible

Z06killinSBF · Dec 25, 2006

Since it seems like your running stock gears, (most likely 2.80's) it sounds like your cam is WAY too big. Bring it down to a smaller cam or put in some gears. That thing is way outta wack. Also like stated above: gears, converter, tires, unhook sway bar, check timing, shift kit, raise your shift points. Keep at it though. Sounds like your having more fun than me

67Dylan · Dec 26, 2006

I forgot to mention frame connectors... keeps the body straight and will improve the feel of the car as it 'feels more solid'. I couldn't believe the difference felt when I installed my first set. Something I recmnd to help w/the suspension.

And I agree w/Z06 Killer; tranny parts. Upgrade the convertor and a shift kit will help it off the line if it feels sluggish. Are you foot braking it?

Bonzo · Dec 27, 2006

Thanks for the replies.
It has stock heads and standard gears and converter( As far as I know).

I hold the car on the line with the foot brake (Auto Box) and build up to 1500 rpm and go.

My plan when next at the track is to give it a service tune the carb and look at the timing. ( can anyone point me to a idiots guide or recomend a setting)

On the line try and build the revs to 2000 rpm leave on the yellow and keep my foot to the floor. Manual change gear at 5000 rpm.

Hopefully times will improve.

Thanks again.

rbohm · Dec 27, 2006

Bonzo said:
On the line try and build the revs to 2000 rpm leave on the yellow and keep my foot to the floor. Manual change gear at 5500 rpm.

Hopefully times will improve.

Thanks again.

fixt

brianj5600 · Dec 27, 2006

The cam and intake should make power to 6000rpm's at least. Timing should be around 36* total. Be sure to disconect the vacuum advance when setting the timing.

Should I being going faster

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