350SB Not All There???

[DaBeast81]

Here it is i bought this 81 short bed a few days ago, the motor is a rebuilt 350 with hooker headers, edelbrock intake, MSD ignition, and a mild cam... But the truck runs like crap, i mean its a great motor, but i can tell its just not all there, i belive it the 2BBL carb on the 4BBL intake? Correct me if im wrong...

Like i said it runs great but i can tell the motor is just running at half potential, any thoughts?

Also when i stomp it to the floor, it bogs at this one point all the time, like 3/4 to the floor any thoughts on that would be great to thanks


81 Chevy K10 Short Bed
350SB TH400
6" Skyjacker
35" BF KO's

[roundedline]

Are you saying it has a 2bbl carb on a 4bbl intake?

I haven't ever had a 2bbl carb bog.

Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
Project Su
Jimmy 2WD Project

[Lt.Del]

Just a stab at it, but are you sure your exhaust is clear of obstructions?  Bogging down could be the result of too much carbon in your muffler or cat. converter.  

Just a possibility.

SgtDel  

[DaBeast81]

Well my engine has a 4BBl Edelbrock intake, and the guy who had it before me, put a 2BBl on it with no adapter. i put a 4BBl from a 350 marine engine on it today and its running great, my only problem now is when the motor is warm and i crank it, it knocks just as it starts up (deisels) other then that it runs great...
Being that it is a marine carb. it has no vacum ports, my power brakes and trans vacum lines are into the port on the intake, but ive got no place to but my vacum advance... so im running without it, and sug.?

[mike357]

if you have the stock GM HEI distributor you can make it mechanically advance only. take the distributor completely apart. the distributor body is aluminum. on the body beside the pickup coil there is a little boss cast into the body. drill a .159 diameter hole in the center of this little boss, then tap it with a #10-32 tap. you'll need to find a small spacer or washer about .210 thick then make the hole in the little tab sticking out of the pick up coil big enough to let the #10-32 bolt go thru. center the pickup coil so the distributor shaft will turn freely and the star on the shaft wont hit the pick up coil. then tighten the 10-32 bolt to hold it in place. reassemble distibutor minus the vacuum aparatus and seal the hole where it went into the distibutor. make sure your weights and springs move freely and operate they way they should and your all set to reinstall the distributor in the motor.
repost if you have any questions and i'll try to explain this better. i have done this before and it works good.

i have even taken the same V8 HEI's and remachined the bodies and reworked the pickup coils and installed them on aircooled VW motors and even an old 50ish model 4 cylinder tractor.

[roundedline]

I wouldn't recommend making it mechanical advance only.  Drivability will suffer, the truck would run hotter at idle, idle quality won't be as good, fuel economy would go down and throttle response would be poor.

If you were talking about a race car that runs wide open for 15 seconds, sure.  But not something you plan to drive at varying speeds.

Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
Project Su
Jimmy 2WD Project

[ChevyGuy]

I have a Mallory Comp 9000 with the mechanical advance and its built in. It seemed to help with startup, milage, and throttle response is great. I tried the mechanical HEI trick and it didnt work at all. I dunno what other people think about actual mechanical advance but ive never had a problem with the distributor I have now and a HEI with vacuum advance.

[mike357]

i never have noticed the overheat thing, but as i think about it, i dont think i have ever ran one that long. it was always for other people. i know the mechanical HEI in a VW really does make a heck of a difference.
chris, what if a guy put some heavier springs on the advance weights. this would keep it from advancing so soon. maybe this would prevent the running hot issue. i dont know just thinking. i have a guy wanting me to do one for his daily driver, but if this is a problem then i wont do it.