The Stovebolt Site Forums The Shop Area The HiPo Shop How to do the timing?

Got my new motor in and it seems sluggish. This is a 430hp, Gen 1, 350 built be The Engine Factory. Motor was supposed to be tuned from the factory, but I thought the truck seems sluggish. Have searched online, but figured I might get another opinion. According to them it should be set at 32 degrees at 3000rpm.

This motor is going into my 65 K10 with an SM420 manual transmission.

Does it have the power at the upper RPM range? Most hi-po engines have all of the power at the upper end because of cam design and wouldn't work to well behind a truck 4 speed,
Scott

Yes, so far most of the power is at the upper end 2000rpm and up.

If that turns out to be the case, and A different tranny is needed, what are your suggestions?

I would put an RV cam in it and bring the power band down,
Scott

Guess I need to do some research. Thanks guys.

32 degrees total is very little. I do perfromance tuning, and usually end up in the 36-38 degree range for total, all in by 3000 rpm, and 18-20 initial. More timing increases vacuum which makes it run much better. Use a vacuum advance as well, with 10-15 degrees of advance built in. You should be able to cruise under no load at 48-55 degrees of total advance.

A performance engine can run with a SM420 trans, but tuning is critical. The torque band needs to be widened as much as possible. You have the cubes to build the torque, so make the best of what you have.

Devin

Thanks 55 tractor, I figure it might be time to hand it over to a mechanic because with me being a "Rookie" mechanic, (and when I say rookie, I am being very kind to myself!), the possibility of tanking this engine after all the money and time I spent on it realllly scares me! I did all this so that I could learn by doing, but I was expecting to do all my learning while I was driving my truck with it's new engine, and rebuilding the old 350 that came out of it. As it is I'm just about out of my one year warranty on the new engine, and it's only got about 2.5 hours on it.

Are you running a regular HEI distributor, or someone's aftermarket design? Most stock distributors require some pretty radical work to the centrifugal advance system to get the right amount of initial advance without over-advancing the centrifugal. I usually reduce the centrifugal advance by about 10 degrees by shortening the length of the slots they move in, and adding the same amount to the initial advance. I like 12 degrees of initial, 24 degrees of centrifugal, maxing out at 2800-3000 RPM, and 10 degrees of vacuum for a total advance of 46 degrees at 3,000 RPM with no load.
Jerry

Thanks Lincoln, will have to run this by my "specialist" as soon as I can get him over.