Went to the track last night. Not totally disappointed but would like to know if my combo will get me into the 12's. Ran a 13.50 with a 2.20 60 ft on street tires (yuck!!), 103 MPH. My combo: 415 SBC (480 HP/490 ft-lb's TQ), XE274 hydraulic flat tappet cam, 10.1-1 SRP flat top pistons, 215 cc Dart Iron Eagle heads, RPM Air Gap intake, 750 Speed Demon carb, Pertronix HEI w/MSD 6AL, 8.8 MSD ignition wires, TH-350 w/ B&M Hole Shot convertor, 2400 stall, 4:11 posi rear with SSM lift bars and boxed upper contol arms. Thanks!!

I'd guess you need some tuning, or you arent' making 480hp...

I run 13.5 @ 103-104 w/ 2.2 60's as well. And I would say that on paper your combo is much better than mine....so I think you're losing something somewhere.

FWIW, I have a 355, with 8.5:1 compression and 76cc factory iron 2.02 heads, totally untouched. (yikes) XE284, 1.6 full rollers, RPM airgap, 650dp, MSD 6AL, 1 5/8 hooker comps, and flowmaster's 2 1/2 exhaust. I also have a close ratio 4-speed, and a 4.66 gear. I KNOW the 4 speed is causing me slower times for my mph. Full race weight is 3750....

I'd think that with your better heads, more cubes, more compression, and more appropriate drag race transmission, that you'd clean up the floor with my car. I'd bet that you have a couple more MPH in your combo, and even with 103, you should be really close to the high 12's.

Hope you find the missing power! smile.gif

chris

2.20 60 ft There's your answer, right there.

it isnt making 480hp... maybe 120hp less???

Wish I was making 480 HP when I go my 13.0@107

My 454 71-velle made 250RWHP and 290 engine Hp.

Bone stock 4 door th400 stoick stall. 3.19 gears. 235/60/15 cooper.

12.94/173 with 2.00 sixtie.

Its all about a good combo. Not HP numbers.

You can have a mid 13sec car or a high 11 sec car with minor mod.s

Dave,sounds like a good combo
Get rid on the street tires,#1
#2 What are your shifting at?
#3 I notice you are in Hawaii,aren't you guys in a funky elevation? What was the weather condtions?
I certainly think your combo can go 12's with traction and tuning

i agree, i would think it should go low 12's, but not with that mph or 60ft. you're definately losing some power from the dyno to the pavement. 480hp should be putting you into the low 12's if not high 11's, depending on some other factors.

A month ago I ran 12.8 on a 2.20 60 ft. at 108mph
with my 406 and 3.36 gears. No slicks , was running 0n 255/60/15 BFG TA radials. You should be faster even on the street tires. Is it maybe leaning out on the top end? Are you shifting it too high, maybe out of its powerband?
With slicks or drag radials you should be able to at least drop a few 10ths but I think there might be some tuning issues too maybe. Enough rambling, Yes you car will run 12's just get some sticky tires and get the motor dialed in.
Maybe try jetting up a couple sizes next time and see if you gain any mph on the top end

Thanks for all the replies. The 480/490 numbers are from the dyno sheet provided by the engine builder. I definately think it's leaning out at the top end. It doesn't pull as hard in third gear. My shift light is set for 5800 RPM so it shifts around 6000 RPM. Should I jet up or change carbs??

Carb should be good enough when its dialed in.
What jets do you have in it now?
Also maybe try shifting at 5500 rpm and see if it makes any dif.

Turbo, what cam/heads/stall are you running?

Thanks, I'm looking to build a stroker or 400sb, and your is running through a TH350/3.36, same as I want to do. Although I just want to run 13s.

.030 400 block, 10:1 compression(est), crane hyd. cam 480" lift 284 deg. dur., AFR 195 heads,
Rpm air gap, proform modified holley 750 vac sec.
I just run a 12" tci sat. night special coverter
but I want to go to a better one this year.
The car ran 13.99 with the old world products S/R
heads(1.94"int/1.5" exhaust valves) and an open diff. I did not get in the 12's till I put the locker and afr's on. Never got to run it with just the locker because I did the head swap also before I went back to the drags, but I think it would have went 13.6 or so with the old heads and the locker. Cam specs are here
http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1972&Engine_Size=262-400%20C.I.&partNumber=100072&partType=camshaft

Sorry to hi-jack your thread DJK.

Have any idea what the race-weight is, Turbo? That seems really good for a 3.36geared car with a 112LSA cam. graemlins/thumbsup.gif

Enrique, I have no idea what it weighs, I wanted to put it on the scales last time I went to the track but forgot. I am amazed that cam pulls that hard also, it just must be a good combination of parts that work well together
Its a 68' 300 deluxe with a pin on fiberglass hood, aluminum headed small block, alum. wheels and a 16 gal. poly fuel cell instead of stock tank, full fact interior. I would say between 3600 and 3800 pds??????? Any guesses??? I should add that I weigh around 200 pds and usally run with about 6-8 gallons in the cell.