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Discussion Starter · #1 ·
I have a 1967 c10 tubbed race truck. I have had it about 8 months and had little success so far due to chasing many issues with it. The truck weighs 3150 with me and a full tank of 112 octane. I have a Chrysler 8 3/4 full spool and 4.87 gear with disc brakes. The tires are 32x14.5 hoosier slicks. I've tried a powerglide trans 1.76 with a 10in 4000 stall and went [email protected] then tried a turbo 350 with a 4600 9in stall and ran [email protected] I switched to a 5000 8in stall and went [email protected] I decided to switch back to the powerglide now I'm looking for the perfect converter for my setup. I currently have an 8inch Hughes "5200" stall. The motor is a 350 .60 over gm crank, hbeam rods, speedpro 12.5 forged pistons, world sportsman 2 heads 58cc around 13.1 compression with a lot of port and valve work they are 2.08 not sure on flow specs. 12-908-9 comp cam..630 solid roller .306 duration @.50. Victor Jr intake port matched. Apd 750 carb and 2inch Apd billet spacer. The motor made [email protected] and [email protected] any suggestions would be appreciated I'm also looking for more power I want to run low 10s I know I could have run low 11s but I only had 1/8 mile passes on my last setup. Any other questions on things I left out just ask
 

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I have a 1967 c10 tubbed race truck. I have had it about 8 months and had little success so far due to chasing many issues with it. The truck weighs 3150 with me and a full tank of 112 octane. I have a Chrysler 8 3/4 full spool and 4.87 gear with disc brakes. The tires are 32x14.5 hoosier slicks. I've tried a powerglide trans 1.76 with a 10in 4000 stall and went [email protected] then tried a turbo 350 with a 4600 9in stall and ran [email protected] I switched to a 5000 8in stall and went [email protected] I decided to switch back to the powerglide now I'm looking for the perfect converter for my setup. I currently have an 8inch Hughes "5200" stall. The motor is a 350 .60 over gm crank, hbeam rods, speedpro 12.5 forged pistons, world sportsman 2 heads 58cc around 13.1 compression with a lot of port and valve work they are 2.08 not sure on flow specs. 12-908-9 comp cam..630 solid roller .306 duration @.50. Victor Jr intake port matched. Apd 750 carb and 2inch Apd billet spacer. The motor made [email protected] and [email protected] any suggestions would be appreciated I'm also looking for more power I want to run low 10s I know I could have run low 11s but I only had 1/8 mile passes on my last setup. Any other questions on things I left out just ask
There are many people on this forum that would know a lot more about this than I do but, I take it that your [email protected] was your 1/8th mile time and the 12's and 11's are 1/4 mile times. Your running a 4.87 rear gear and only picking up 13 MPH in the last 1/8th mile and it takes you 4 to 5 seconds to get that 13 MPH...do you think you might have to much gear and the converter is OK. Maybe try a 4.10 or so rear gear..Just thinking?

Ray
 

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Discussion Starter · #3 ·
The 1/8 mile time was a different setup converter wise... I'm assuming just by how the truck responded I would have been around 115-118 mph I've been told to go with a higher gear to try 5.13-5.38 but I'd rather not even change that part..
 

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Like I mentioned, many people would know more than I would but, what RPM are you going through the traps at on the 12.60 and 11.71 runs?

I had a Firebird years ago, 400, with a 4.88 rear gear, similar horsepower and torque but at a lower RPM and more weight. I was running consistent 12.3's @ 109, went to a 4.11 and ran high 11's @ 117 MPH. I ran out of motor before I ran out of track with the 4.88 rear gear, now that might be the the RPM difference, your running peak at 7,000 and I was at just under 6,500. I did notice that I wasn't coming out of the hole as quick but sure made it up at the big end.

If you don't want to change the rear gear, I don't know if a converter is going to do it for you, but let's see what the guys say that really know what their talking about...because I don't profess to be the ultimate expert on this stuff.

Ray
 

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Discussion Starter · #5 ·
I'm at 6800 at the lights. The 12.60-11.71 et difference was based on a bad converter.. I run 1.52 60ft spinning a little I know the truck should run 10.50s just haven't had time to fine tune... I'm running alky next season
 

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If your hitting the traps at 6,800 wouldn't a 5.13 or 5.37 rear gear be a bit much? At what RPM do you make your peak torque and horsepower on the power curve? If your spinning out of the hole and running a 1.52, 60 foot, is there anything you can do suspension wise to cure getting a bit loose at launch? What are you doing for rear suspension?
 

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Discussion Starter · #7 ·
I thought going to a higher gear would be to much also that's why I don't wanna change that part.. I run ladder bars with adjustable coil overs I've changed a little bit but not sure what to do
 

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The stall speed should be as close to the torque peak of the engine as you can get.

I think you're a little too heavy for a PG, but it might be more consistent if that is important.

Ever consider a TH-type input so you could try all the converters you have for them?

It seems the trap speed is not showing the amount of HP that would be happening so high in the rev range. Because of this I tend to believe you need less rear gear, too.
 

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Discussion Starter · #13 ·
The highest gear set I've found for an 8 3/4 is a 5.38. What about switching to a set of brodix 23 degree spreadport -11x heads cnc ported would that be to big of a head for it?
 

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hello
I'm guess'n your 67 is a short box.. but how are you at 3100 lbs with fuel and you??

my 71 is 3987 ish 350/350th 2wd tho. mine is a long box.. I can't see a 1000lbs difference..
you have a r/bar
sorry can't help with the stall.. good luck
 

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Discussion Starter · #17 ·
Na not much money in my setup... Sounds like I gotta swap the gear didn't want to change it cause I just put it in there.... I was just hoping for another answer.. always looking for advice and new ideas. I don't like power adders much at all but if I did it would probly be nitrous. I think I have 6,000 in my complete setup turnkey from motor to axle wheels tires everything. I'm very low budget I do what I can with what I have. Hint, I run cheap stock replacement sportsman2 heads its all about work not $$.
 
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