Thread: Problem with my Small block Chevy

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Hello all, I have a question for you Chevy people out there.
After searching and asking everyone that I know, I have not found even the slightest answer to my dilemma. I have an 81 Z28, 4 Speed, with a 69-70 sb 350, I have 64 cc 2.02/1.64 cast heads with screw in studs and 1.55 Crane gold roller rockers, Eldebrock Scorpion intake, 10.1 flat top pistons. I am running a #12-213-3 Comp 501/501, 292/292 duration cam, and a 625 Demon carb. I also have an MSD ignition running with a Mallory coil and distributor.
Now... my problem; At take off, the car is great, no problem. It takes off strong, but at about 2500 rpm it hits a dead spot, sort of a sputter. After passing that rpm range it is strong again.
This motor has less than 2000 miles on it, all rebuilt. New Ram clutch etc.
If anyone knows what could cause this, please... HEEELP!
Thanks

What kind of timing are you runing? That engine likes a lot.
Ed

Well, I am running a Mallory unilite. And Mallory coil. As for the timing setting, I am not sure what it is set at exactly. The MSD is the 6-A model.
I was wondering if possibly it could be the gap in RPM range between the intake and cam?
I don't know, and I am grasping at straws at this time!

Well...........?
Still havin' the problem... and I am still not sure what to do.. heh I am thinking of going to a solid lift cam... with a higher rpm range.. not sure yet....

I'm not familiar with Demon carbs, but your symptoms with any carb with metering rods or even a Holley-type power valve would suggest that it's not going to high-speed rich soon enough. It leans out for a few hundred RPM , then the metering system kicks in and it smooths out.

Well, I figured it out... heh heh
Bigger cam, went solid as mentioned before. That solved the whole problem. She runs great now!
An other mod, I replaced the 4 speed w/a turbo 350 *built* and a 3800 Stall.
The Sag.. 4 speed was getting more than tired, and becoming harder & harder to shift..
So, until I find a good 4 speed for her, she is auto. I did keep everything though, all linkage etc. I even left the clutch petal in. *goona' miss it*
But it is only temp... I already do not like the auto.. blah
but, what else was I goin to do? I am far from being made of money. And I am goin' to need quite a bit to buy a good 4 speed. Oh well...
Thanks for all your help!