Bee Jay: I was thinking of a little less throttle off the line till you hook.
I believe you were spinning too much off the line? The ultra low gear is working against you. Just a hair less, then mash it!
Since you are so close, it shouldn't take much to make 12s.
You have better heads and I have TFS w/218/224 HR w/1.6s.
280 rwhp & 315 rwtq.
I want to join the 12 sec 20 mpg club. Looks like you're there!
I can't wait for headers and new ex.

R

 

OK, so I should lean on the converter with the brakes locked, and not mash it to the floor so quickly when I release the brakes. I'll give it a try.
Bee Jay

 

Bee Jay...

You need to get to a track so we can see your 60Ft time. If you are cutting 2.0 or higher that is what is hurting your E.T.

If your G-tech is even close you should be mid to low 12s

And yes... lean on your Converter for a better launch but not to the point you roast your tires down the road.

My last time with my 346 so 12.00 @115 with a 1.72 60ft

Of course I am running a 275/60R15 Mickey Drag Radial... 3000 stall... and 3.36 gear

My new motor has a 3,500 stall !!

Good Luck !!

 

What stall speed is your torque converter? Stall speed and traction are what will maximize your ET. You should also get to a drag strip to get more data, like 60 ft times and more accurate data. With a lot less power, I've run 12.66 with a 1.75 time for 60 ft. Thats with drag radials and a 3,000 stall converter. I have run 12.9 with BFG radial TA tires, so you should do that easily. My MPH lately is 105.

 

i run a police package 700r4 convert on my 327. stalls around 22 to 2300. also it has the lock up to. sorry beejay, i don't know where i got the bfg tire thing from. if you are spinning the hell out of the rear tires on launch you are wasting time. leave as hard as you ca without spinning and you will be well into the 12's. that is a high mph speed.

 

Gosh darnit. I'm so close I can taste it. I did five passes this morning, the last and best pass was a 13.04 @ 114.8 seconds. I leaned on the converter and launched at 2500 rpm, and the rearend went up, giving me an almost 14 second pass. I tried at 2000 rpm and it worked much better. My 13.04 pass, I launched at 2000rpm and the car actually bogged for a moment. I almost terminated that run. The secret is to find a good clean spot to launch. I bet a sticky drag strip would be good, but the nearest strip is almost 100 miles away in Bakersfield. Maybe I should have tried a sixth run, but I didn't want to push my luck. This weekend, I'm pulling the cam and intake. The hydraulic roller LT4 Hot Cam and the Edelbrock Performer RPM Air Gap are going in. I want a 12 second pass.
Bee Jay

 

Did you lower those tire pressures any further on this last test? Also on street tires you should do a very short brakestand just to clean the rubber off....very very short...were with ya cheering ya on

 

BJ,

Get yourself a pair of 15x8 rims and use a set of MT Street ET (drag) Radials - 275-50-15s work fine.

Go to a track which will have a prepared launch area - it will be stickier than a public road.

Do a nice burnout (crowd pleaser!)

Run in low 12s or high 11s!


__________________
1978 Corvette
406 SBC AFR heads Lunati roller Quadrajet TH-350 3.08
11.59 sec / 118.9 mph 1/4 mile

 

Dang dude, you run 11s with a Small Block, Turbo 350 and Quadrajet? Where do I go to learn more about your car? After I finish this cam and manifold install, I want to build a 396 small block.
Bee Jay

 

Although more cubes is nice, you've got the HP to get down to the low 12s or better - just make it hook! Oh, BTW, AFR heads help too!

As a rule of thumb, if you multiply the first gear ratio times the rear end ratio and it is greater than 10, you'll have problems. If the torque converter has higher stall and greater torque multiplication, the problem becomes worse - that's why my tight 10 inch Continental converter (2,800 brake stall) works so well with 3.08s to get me a 1.75 sec short time.
__________________
1978 Corvette
406 SBC AFR heads Lunati roller Quadrajet TH-350 3.08
11.59 sec / 118.9 mph 1/4 mile

 

Larry, were you having traction issues with your passes on your 1.75 short time runs? I am just curious because it seems like your motor makes great power, I would have thought you would have be low 1.6 60's, if not high 1.50s.... You think the 3.08s are killing it?

I am curious because I will soon be testing mine out and I will also be attempting to run 3.08s. I would like to keep the 3.08s for freeway driving but I want it to ET well also...Don't see too many others trying to drag with 3.08s. I am hoping the converter will make it up. On my last old street/strip car, I would 60' 1.62s with only 3.42 gears but it was with a pretty loose converter and 406" BB Pontiac torque. I am hoping to get those 60's at least with my vette and 3.08s.




BEEJAY, sorry for the thread jack....you really need to get that car to a drag strip and see what its REALLY doing before you tear into the motor. I drive 65 miles 1 way to the drag strip about 3 Fridays a month to race my bikes, another 40 miles would be worth it to get some real numbers on a sticky surface. Those G-Tech things are WAY off in speed. We tested one of the early ones at the drag strip a few years ago...it was actually only about 2 tenths off in ET(G-tech was slow) but it was like 8 mph fast compared to the real trap speeds.

That being said, I still think your car will go 12.80s on a real drag strip in decent air if the DA is under 2000' AND the car half way hooks up. Make a trip to the strip and you will be hooked.

 

No criticism of larrywalk intended here because he's going alot quicker than I am, but at almost 119mph, that car could be going 11.20. I think that 3.08 hurts rather than helps. I run 1.75 short times at only 104/105mph, with a 3.73 gear.

 

Everything is a compromise... When I ran RE gearing variations on Quarter Jr., for every 10% lower, i.e., 3.36, 3.70, 4.11, I went a tenth quicker, but the speed only increased by 1.5 mph for 3.36 or lower. Also, I would be worried about the upcoming breakage barrier and I didn't want to go that far. Finally, I'd be giving up mileage!
__________________
1978 Corvette
406 SBC AFR heads Lunati roller Quadrajet TH-350 3.08
11.59 sec / 118.9 mph 1/4 mile

 

Yeah I hear ya....I would definetly give up 2-3 tenths in ET to be able to drive it 70-75mph on the highway as opposed to 60....

But then again, if I am running 11.0s-11.10s I will be kicking myself for not having 3.55s or 3.70s...to squeek into the 10s with...

 

The 700R4 conversion catches some flack here, but that was on of the best, top three for sure along with the AFR heads and C5 wheels and tires, the best mod I've ever done to my car. The car is fun as hell in the first three gears, and when I get up to highway speeds, I put it in fourth overdrive. Once I get up to my ultra legal cruising speed, I switch on the lockup. I drove this car for years with just the 3.55 and the turbo 350. No OD and no lockup. You have no idea what that OD does for you. Every once in a while I leave it in third to remind me of what my top gear used to be. When I do the 1/4 mile, I go thru the traps in third at about 114mph not even close to redline. Redline is about 140mph.
Bee Jay