350 - No power, won't rev up

what's up hot rodders

my 350 chevy motor for some reason won't rev past 3500 rpm while on park, throttle response is not at its best. Does anyone know what could be the problem with it.

thanks


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Have you changed anything recently? What ignition and carb are you running? Points or HEI? Have you tried a tune up? What SBC, 350 or 305? Does it rev past 3,500 in gear?

Welcome to the board

We need much more information, year, intake, ignition, vehicle, etc.

I've seen loss of power from collapsed mufflers and cats, but without more info hard to tell with yours. Is this after you added something, did work on it?

You also need to title your threads correctly, something like "need help" or "engine problem" doesn't work well, read the guidelines. I'll change it here.

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X3 more info please.




Cole

I purchased the truck from a friend that purchased it from another friend. I don't know the history behind the engine and what was the issue, i just got basic information.

Motor is a 350 between 70-80, it has an MSD pro billet distributor, MSD blaster 2 coil, MSD 6AL box, Holley carb. I've recently did an oil change when i got the truck, i haven't yet did a tune-up on the engine.

I hope this is enough information to help find the issue.

Thanks

Check the MSD box to be sure there is not a rev limiter pellet in it to start with. After that I would look at the float levels.

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Chet

Ok, so I took a look at the ignition module it has an 8000 module. I've checked the carb it's a double pumper, but a performance carb, the vacuum seems fine and no leaks. Could it be a breathing problem coming from the top end or is it time for an engine rebuild.

Pull out the 8000 pill to see if it improves. You will now not have any rev limit- but w/an 8000 pill you really didn't, anyway.

to Cobalt: Valve float = rev limit?

What kind of exhaust system do you have? Id say disconnect everything from the mufflers back and see if that helps. Ive also seen some clunker MSD parts but they make zillions of em, there's bound to be a few clunkers.

What kind of oil pressure are you getting?
what kind of fuel system is on this?
Have you set the timing? Check the timing marks too, sometimes that ring can move and cause all kinds of hell although I doubt it

Does it sound good? no popping, pinging or back firing?

Motor run and idles fine, I've also notice that while slowly revving up towards 4000 rpm I hear a slight knock. Oil pressure will be up at 40 psi and then drops down to 15-20 psi and remains there. I removed the pill and still same thing. It has hook headers with dual flow masters, it runs on 87 octane pump gas. I will detach the exhaust system over the weekend and see if there is a change.

Stand fast,

Sounds to me like you're well on your way to spinning a bearing. This isn't going to be an easy fix, plan on pulling the engine and disassembling it to get to the root of the problems. I'd also avoid running it until you've at least pulled the pan and inspected the bearings and journals.

Sounds like I'm going to have to pull the motor out and rebuild the whole motor.