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Discussion Starter · #1 ·
...for the first time in over a year! I'm pretty excited, it's been too long. I must admit I was a little nervous because of all the problems I had the last time it ran. But it cranked right up and idled all by itself on high idle.

As it warmed up it the idle got a little rougher and it died about three times, choke might be coming off a little fast. A little turn of the idle screw helped.

I probably need to get the timing dialed in a little better. I'm sure the vac advance is active at idle and probably needs to be, but I don't know how to make it better. Ideas? Should I post in "engine" or "performance"?

The year in review:
A screwed up electric choke fouled the plugs and the fuel filter was leaking.
So it got:
New plugs (have to drop one header).
An auxiliary fuse box to solve the wire issues.
Moved the temp sender to cure header tainting.
New fuel filter (TC gave me the ideas for this one - thanks guys).
New fuel lines between pump and carb.
Coolant bottle, just for kicks.
Switched oil to Rotella T 15-40
 

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Tell me a little about your build? large cam? initial and total timing. You will want to adjust curb idle with timing, as most people think the primary butterfly (idle screw) is used to adjust stationary idle which is incorrect. You must open just beyond exposing the transfer slot (this is very tempermental with certain carbs) and unless you've got a vast amount of experience with this, it must be performed while the carb is off the block. Finally get correct fuel air with the appropriate mixture screws. If you come off of the idle circuit, you risk having your mechanicals come in to soon, and this will throw off your timing curve. A fresh rebuild will really benefit from being a little fat (rich).
 

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Discussion Starter · #4 ·
Tell me a little about your build? large cam? initial and total timing.
It's Edlebrock RPM Cam, Intake, Heads and 750 carb, Mallory Unilite. 327 CID. I was going to check the timing but my Mac dial back light was not working. I haven't messed with the timing in a couple of years, but I do know that I limited the mechanical advance to allow more base timing.

Thanks for the comments, they are confidence inspiring. I'll be on vacation for a week, but I'll dig into this when I return and post again.
 

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Discussion Starter · #5 ·
Okay, back from vacation and tinkering with it again. I yanked the distributor tonight, an Mallory Unilite, to check the amount of mechanical advance. It was limited to 18 degrees. This would allow me as much as 18 initial, which I'm pretty sure I didn't have before I yanked it out.

This seems like a lot, but maybe not as I'm learning from TC that with a performance cam a lot of initial timing. I would add some vac advance on top of this.

I don't know where the advance starts to come it. It's a YL advance, and Mallory didn't have this curve on their website. Would anyone happen to know?
 

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My opinion is you may want to use a smaller carb........ It will run better. Just one guys opinion though and it is worth what you paid for it! :)
 

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Discussion Starter · #7 ·
The 750 is the Edelbrock carb spec'd for this set-up, except for 4% leaner on the power circuit than their recommended tune-up I would generally agree with your opinion on carb size and if I were running a Holley, it would probably be a 600 CFM 1850. But I still have to get the timing right -- you can tell as the RPM starts to drop that the advance is coming out of the distributor, which only causes RPM to drop further until you goose the throttle or it dies.
 
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