I need anyone's advice, please HELP...

[corey]

My brother-in-law has a 1980 Chevy truck with a 305 small-block and a TH350 tranny in it. He wanted a little more power so these are the things we did...

1> installed a Edelbrock performer cam
2> installed a double roller timing chain with the keyway set at 0
3> installed a set of Edelbrock sure-seat valve springs and new valve seals
4> installed a Edelbrock performer intake
5> installed a Holley 600 carb with vacuum secondaries
6> installed a curve kit in the HEI distributor (we used the lightest springs)
7> installed new plugs, wires, cap and rotor

The truck has true dual exhaust with stock manifolds and mufflers. Also, everything else is stock like the heads and bottom end of the motor.

Here is the problem, the truck idles smooth and has awesome midrange and top end power, but no bottom end power. I mean if you punch it from a stop it will not break the tires loose. When you punch it from a stop it does not cough or stumble it just acts like it has no tourqe.

So we called Jeg's techline and he said it sounded to him like a carb issue and gave us Holley's techline #. We called Holley and the tech told us how to determine which power valve we needed and change it and we did. This did not change a thing so, we still have the problem...

I am dumbfounded and don't know where to go from here is there anyone that can help me?

Thank you for your time, Corey

[06slobolt]

Sounds to me like a cam issue. you should find out what the cam you put in is built for. If the cam you put in was not built for low end tourqe then thats probibly your problem. make sure your intake is dyno matched for the cam you put in as well.

[MadJack]

Is your vacum advance hooked up? If so is it hooked to a ported vacum source or a maniflod vacum source?(Should be a ported source) At what rpm is all your advance in? The mechanical advance should start at approximately 1500rpm and be all the way advanced by approximately 3000rpm.

Are you still running the stock torque converter? If so the stall speed might be too low. Since your dealing with JEG'S, look at their 555-60402 TC 2000-2300rpm stall, the TCI Saturday Night Special, The Hughs Street rod or the B&M holeshot2000 or Torque Master 2000. These TCs will allow your motor to get up into the power band beforethe truck starts to move under WOT acceleration. You will generate more heat, which is the killer of transmissions, so get an auxillary tranny cooler to keep the temps in check.

As far as the parts are concerned, that is a good combination, they match eachother perfectly.

[ricefed]

Find the cam specs. You may need more to support the cam range. For example my cam requires a 2400 or higher stall converter, headers, rear gear, intake and lots of tuning to work correctly. The cam may be set for more torque than hp. Was the truck used for towing? Regardless a higher stall and a higher gear ratio should help out alot.

[MadJack]

Specs on the Edelbrock Performer cam: 204/214 @ .050, 112 LSA .420"/.442" w 1.5 rockers. A 2000-2200 stall TC and a gearing in the low 3's would work great with this combo. He may have the 2.84:1 gears, which an upgrade would be called for. Switching from 27"(stock dia) tires to 25" would also give an equivalent of 3.06:1 gears. The shorter tires might look a little funny though.

[ricefed]

That cam can't be much larger than stock. Maybe like one size up. Smaller tires would look funny. If anything a larger rim with a lower profile tire would break free easy. Another thing to check would be the timing. If it's off by a little you loose power down low.

[Danmuzicman]

yeah sounds like you have a cam/ carb set up that is making high end toruqe and no low end. try rejetting. and if you can find out what your cam is supposed to do. i once got shipped a wrong cam. we put it in my friends Z28 and it did the same thing.