I finally ran the Chevelle with the 421. I ran a best of 11.82@114mph. 60 ft was 1.72(wish I had a bigger stall and a T brake) The car never left the 11's. I think I made about 6 or 7 passes, all while trying to race the Pro Bracket with the Camaro. I lost in round one, but it was a good race day because everything went fine on the Chevelle. Only thing is it's at 6500 Rpm in high gear by the 1000 ft mark. I guess 3.90's or 4.10's should be better. Peak horsepower is at 6000 rpm so no sense in making it turn too much more than that. Haven't touched the timing or adjusted the carb yet. But I don't expect much more without the gear change. I'll try and run the Chevelle in the 11.90 index tomorrow night. If the reaction is good, I have a real shot at winning. Gotta love the .500 Pro Tree. I'll update on Sunday. Thanks for all of the info and support. THis is the best forum on the planet. :D

Jay

With 4.10 I think your time might improve, just a novice opinion though.

Yeah get those gears figured out cause it sounds like you could surely use a little less. Theres a good possibility that after the gear swap, the issues you have with the current converter not stalling high enough will be amplified a bit cause you wont have as much gear to get you out of the hole. The again, if its a loose converter, less gear will load it harder and it may stall higher than it does now.....enough to be acceptable maybe. Either way, it all sounds nice and 11 seconds in a small block street car(even though its a big small block) is something to feel good about. Put some 355 stickers on the air cleaner and make all the locals feel dumb.

Just curious, whats the rest of your combo look like?

Thanks for the input.

Greg,
I do have a 3800 stall Continental converter lying around somewhere. I might try that with a 3.90 gear. Just sounds better than 4.10. Well I might be getting a ford 9" bolt in rear for the Chevelle, but don't know who to get it from. I think ford's gear would be a 3.89. With the 3800 stall, I ran a 11.98@111mph when I had my 406(BRE Racing Engines) with a .495 .510 lift 246 254 @ .050 hyd cam 112 LSA, 9.6 to 1 comp, sportsman 2 heads with 2.05 valves, fully ported, and port matched vic jr. Carb was a 750 HP holley out of the box.
New combo:
421 .583 .589 solid roller 250 and 260 @ .050 110 LSA, guessing at 10.25 to 1 comp(idiot crate engine builder grinded some solid dome JEs down to a flat top kinda)Maybe some cylinders have 10.5 to 1 and some get 9.8 to 1. Don't know as they used a die grinder and none of the pistons look the same. Pro topline iron heads 2.02 valves 64 cc?(don't know again, never checked but says 64 on my invoice) I believe it is a 220 cc runner fully ported, Pro Products(junk) hurricane intake portmatched. It's really tall. Horsepower ratings has 570@6000 and tq 550@4800.
406 was 523@5900 and tq 498@4800.
I was hoping for more but we'll see after the gear and converter swap. Converter is extremely tight. Then maybe a trans brake at the end of the year.

Jay

I got the Chevelle down to a 11.76@116 mph. I had a little tire spin. Next run was a 11.83@105(trying to slow for the 11.90) but the 60 and 1/8 mi times were better than the first run. I lost in the first round thanks to a horrible .632 reaction on a .500 pro tree. I did get a better 60 and 1/8 than the first 2 runs. I think that this 4.56 gear may be good after all. On these runs, I shifted early(5900 from first and 5300 from second to third) and had 14 psi of air in the M/T's. Shifting at 6000 and 10 psi(yesterday's runs) only got me a 11.82@114. Maybe not enough air. Didn't try to go all out on the shifting tonght because of running the 11.90 index.

Does anyone know if there is something between 4.11 and 4.56 for a ford nine inch or chevy 12 bolt?



Jay

Nice times :thumbsup:

The olds type 'o' axle has a 4.33 gear available...

Nice times :thumbsup:

The olds type 'o' axle has a 4.33 gear available...


O axle? Is that the BOP 10 bolts? I have one with a 3.90 gear but I thought it was too weak for this setup. Haven't broke it with the 406 but, was getting a little scared. The reason we ran this rear is because it don't have c clips. I was hoping for a nine inch with that kind of gear. Is there such a ratio? THanks


Jay

Richmond makes a 4.33 and Precision Gear makes a 4.30 for a 9 inch I'm sure there are others.

pretty good times for a new motor. what are your best 60', 330', and 660' times and what mph is the 1/8mi? i would think that it could 60' in the 1.50's if you had the right convertor, gear, and tire set up. how on earth does your car weigh 3900lbs?

Richmond makes a 4.33 and Precision Gear makes a 4.30 for a 9 inch I'm sure there are others.

Thank you Frank. That was my next option, to go with a 9 inch currie or moser.


Jay

pretty good times for a new motor. what are your best 60', 330', and 660' times and what mph is the 1/8mi? i would think that it could 60' in the 1.50's if you had the right convertor, gear, and tire set up. how on earth does your car weigh 3900lbs?

Best 60 was 1.708 but didn't get to make an all out pass as this was eliminations for 11.90 index. 330 was 4.839 1/8 was 7.525@92.01 and best 1000 ft was 9.830. Right now I am running a 2400 continental, actually it stalls at 2300, maybe less. TIres are M/T Et Drags 28x9x15 and 4.56 gears. I really want to see what the car will run with the 3.90's and a 3500 stall. But I figure the best gear would be a 4.30 or around there with the 3500 stall. It should run in the 11.40s, I hope. I am planning to make a short 3" exhaust system with some race mufflers like the dynomax or borla straight through design and maybe keep the tail pipes. I would also like to get the 275/60/15 M/T Drag radials. Hopefully 11.50's in street trim. We weighed the car with me in it at a certified scale station. It is all metal and nothing is missing besides the A/C compressor and the A/C lines. Well I am 250 lbs, so that will make it heavier than most. :D


Jay