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-   -   What's it gonna run? (https://67-72chevytrucks.com/vboard/showthread.php?t=380258)

bigsnookmaster 01-09-2010 09:25 PM

What's it gonna run?
 
2 Attachment(s)
I'm in the finishing stages of my truck, and would like to get a little input from the pro's! It's a 68 short stepper, 406 sbc,studded bottom and top,splayed caps,10.7 to 1 comp. Victor jr heads and intake,Jesel shaft rockers,Comp mech roller w 4/7 firing swap,.571-.577, 242-248 @ .050,110 cl, Isky red zone e-z roll lifters,manton stage 5 pushrods,Pro Systems 832 built for the motor,Fluidamper, Msd pro billet w/6al, elec. water pump,fuel pump, and fans.Super comp coated headers and 3' mandrel bent exhaust with x-pipe. Turbo 400, 3100 converter, 9", 3:70 gear, all good internals, stock trailing arms with light rear spring with air-lift drag bags, 29-15.5-15 Mickeys. I'm guessing about 4000lbs. with me in it.I'm gonna show the truck, but I'm gonna race it first! All input would be appreciated. Here's a couple of pics:

nxtruck 01-10-2010 12:53 AM

Re: What's it gonna run?
 
VERY nice truck you have there! Nice job! I'm no pro, but here's my $.02 worth.
With the setup you have listed, I'm going to say that it should run in the 12.20 -12.40range and maybe run a 12.00 with some tuning and good weather and track conditions. If you get serious about racing it, I'd look into a looser converter and a little deeper gear for it. Those two changes would knock some more e.t. off of it.
Again, great job on a great-looking truck!!

bigsnookmaster 01-10-2010 10:51 AM

Re: What's it gonna run?
 
Thanks Chris, My old combo ran 7.90s in the 1/8th. I have a lot more motor and tires than I had with that combo. I'm hoping for 6.90-7.0s. I could be wrong though. I am going to mostly drive it on the street, with an occasional trip to the strip. It runs and idles in gear very well and is very responsive! I really think the 4/7 firing swap makes it run so well, it really has better harmonics, and runs smoother than any other engine I've ever run. Please keep the responses coming. Thanks, Greg

Marv D 01-10-2010 01:06 PM

Re: What's it gonna run?
 
Very VERY nice build. That truck is simply stunning.
Couple of things I have questions about.

Why so little lift??? The rocker setup could easly get 1.7 or 1.8:1 if necessary to get lift up where those VicJr heads come to life (up around .65). Myself I think that would sure wake things up. You appear to have the RollsRoyce of parts in there, just wondering why not a custom cam to compliment the rest of the package.

Second,, I'd pull that Fluidamper and put a good ATI dampner on there. It just never made sense to me.... spend good time and money for a 1/2 gram balance job then put a liquid-filled damper on the front of the crank that has to 'find' it's happy place with rpm's. But that's just my 2¢

I wouldn't make any guesses what it might run now. Especially not knowing what traction is going to be like. You said you have more motor and tire than before, but what was the 60' before and what is the difference in tire and what kind of tire you running now?

bigsnookmaster 01-10-2010 03:40 PM

Re: What's it gonna run?
 
Quote:

Originally Posted by Marv D (Post 3721970)
Very VERY nice build. That truck is simply stunning.
Couple of things I have questions about.

Why so little lift??? The rocker setup could easly get 1.7 or 1.8:1 if necessary to get lift up where those VicJr heads come to life (up around .65). Myself I think that would sure wake things up. You appear to have the RollsRoyce of parts in there, just wondering why not a custom cam to compliment the rest of the package.

Second,, I'd pull that Fluidamper and put a good ATI dampner on there. It just never made sense to me.... spend good time and money for a 1/2 gram balance job then put a liquid-filled damper on the front of the crank that has to 'find' it's happy place with rpm's. But that's just my 2¢

I wouldn't make any guesses what it might run now. Especially not knowing what traction is going to be like. You said you have more motor and tire than before, but what was the 60' before and what is the difference in tire and what kind of tire you running now?

Thanks Marv, This is the custom cam that comp recommended for the combo. I decided on the 4/7 swap, it just made sense to me. It does run much smoother. I am mainly going to street drive it, and it has a/c and power everything,that's why I didn't go bigger on the cam. It also runs on pump gas, I have coated pistons and combustion chambers also. Before with Dunlop 275-60-15 tires my best 60' was a 1.76 I'm going with Mickey Thompson Sportsman pro's this time I believe. 29.5x15.5-15 The old combo was a 406 with Sportsman II heads, .507-.510 hyd cam, perf. rpm intake, 750 holley and a 2-1/2" exhaust with crossover pipe, nothin special. It was a 3:73 rear with a 2600 converter also. Thanks,Greg

TwoFiftyShifter 01-10-2010 05:32 PM

Re: What's it gonna run?
 
12.2 @ 114

bigsnookmaster 01-10-2010 05:36 PM

Re: What's it gonna run?
 
Old combo went 13.12 at 103 with some traction problems.

nxtruck 01-10-2010 08:15 PM

Re: What's it gonna run?
 
Greg,
Looks like a pretty drivable combo to me. If your truck will spend more time on the street than at the track, I think you'll be happy with it. You could always raise the compression ratio and put a bigger cam in it, but then you're looking at running race fuel in it and wearing out valvetrain components faster. I've been down that road with my last motor ( a 14:1 421 sbc ) and I'm a lot happier with the 10.6:1 434 that I have now. The truck runs within .15 of what it did with the higher compression motor in it and doesn't break valvesprings or require race gas to operate.
If you find yourself looking for more, you could always spray it. With the gear and converter you have right now, it should respond pretty well to nitrous.
Good luck with it!

bigsnookmaster 01-10-2010 08:26 PM

Re: What's it gonna run?
 
Quote:

Originally Posted by nxtruck (Post 3722677)
Greg,
Looks like a pretty drivable combo to me. If your truck will spend more time on the street than at the track, I think you'll be happy with it. You could always raise the compression ratio and put a bigger cam in it, but then you're looking at running race fuel in it and wearing out valvetrain components faster. I've been down that road with my last motor ( a 14:1 421 sbc ) and I'm a lot happier with the 10.6:1 434 that I have now. The truck runs within .15 of what it did with the higher compression motor in it and doesn't break valvesprings or require race gas to operate.
If you find yourself looking for more, you could always spray it. With the gear and converter you have right now, it should respond pretty well to nitrous.
Good luck with it!

Yeah, that's kinda what I was thinkin, I do have a another intake already plumbed with a Pro-Shot fogger system. Thanks, Greg

limitedstreetoutlaw 01-11-2010 03:25 PM

Re: What's it gonna run?
 
WOW sweet truck man i love that color. just a guess on times i would say 12.40 to 12.00 maybe with good traction

bigsnookmaster 01-11-2010 07:23 PM

Re: What's it gonna run?
 
Quote:

Originally Posted by limitedstreetoutlaw (Post 3724213)
WOW sweet truck man i love that color. just a guess on times i would say 12.40 to 12.00 maybe with good traction

Nice truck also, Brandon I'm really anxious to get it to the strip. Our local track is 1/8th mile, so that's what times I will be posting. Thanks for all the responses, keep em coming! Greg

Alex1 01-11-2010 08:01 PM

Re: What's it gonna run?
 
I say 11.90's

djracer 01-11-2010 09:29 PM

Re: What's it gonna run?
 
beautiful truck I would say it needs a little spray. Your combo looks to me like its begging for it. I would say upper 6's in the eighth with a little spray.

Hart_Rod 01-12-2010 11:17 PM

Re: What's it gonna run?
 
I'm not sure how fast it will run, but it sure looks awesome!

bigsnookmaster 01-13-2010 08:38 AM

Re: What's it gonna run?
 
Thanks for all the replies and nice comments. I will post times as soon as I run it, probably within a month or so. Thanks again, Greg

bigsnookmaster 04-06-2010 08:37 AM

Re: What's it gonna run?
 
Went to the track Wednesday night, ran 7.86 at 85.95. Slower than what I was thinkin, but I'm still impressed the way this thing drives. It's got more in it with some tuning and traction. Went to a local car show Thursday and got Best of show, and Best GM on Friday Nite at a different show. I'd like to go faster, but I don't really want to make a race truck out of it. I still have the fogger setup if I really want to go faster.

nxtruck 04-06-2010 12:56 PM

Re: What's it gonna run?
 
Well, keep tuning on it, both engine and suspension-wise and you may get some more out of it. If you really get the urge to run quicker, spray it! But, most importantly, enjoy the fact that the truck looks as good as it does and that you can drive it!!

Marv D 04-06-2010 08:05 PM

Re: What's it gonna run?
 
If this means anything,,,,,,, The formula I use to convert 1/8th to 1/4 is (1/8th ET +.022) /.655

That's almost a 11 second driver,, I wouldn't be too disappointed!!!!

bigsnookmaster 04-06-2010 10:58 PM

Re: What's it gonna run?
 
Thanks for the comments!

Shon 04-07-2010 08:37 AM

Re: What's it gonna run?
 
Just asking the question, not questioning the formula b/c I had a formula for the F-bodies I owned and it was very consistant and it was slightly different.

Why are you adding the .022 to the 1/8th ET?

With my 94 Z28 I used 1/8th / .64x, this was after taking it to the 1/4 mile tracks and getting a ratio for that car and it worked.

Never saw the addition of a factor and it may make sense with the 'areodynamic' trucks. Just wondering b/c I want to figure out what my truck does in the 1/4 without going....

Quote:

Originally Posted by Marv D (Post 3904886)
If this means anything,,,,,,, The formula I use to convert 1/8th to 1/4 is (1/8th ET +.022) /.655

That's almost a 11 second driver,, I wouldn't be too disappointed!!!!


71chevytruckguy 04-07-2010 09:58 AM

Re: What's it gonna run?
 
Slick looking truck man. Nice motor. Seems like it should go a god bit quicker than that no prob. What's your 60'? Chris.

bigsnookmaster 04-07-2010 11:35 AM

Re: What's it gonna run?
 
Quote:

Originally Posted by 71chevytruckguy (Post 3905964)
Slick looking truck man. Nice motor. Seems like it should go a god bit quicker than that no prob. What's your 60'? Chris.

1.73 - 1.75 I think with a little work it will go better.


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