# CHEVY 350 POPPING THREW MY CARB



## 64 CRAWLING

I GOT A CHEVY 350 WITH EDELBROCK INTAKE HOLLY CARB,, WEN I PUSH ON GAS TO A HIGHER RPM THEN IT STARTS TO DO THE POPPING SOUND THREW MY CARB, IS THIS CAUSED BY 1 OF MY LOBES WORN OUT ON MY CAM SHAFT??


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## CoupeDTS

> _Originally posted by 64 CRAWLING_@Feb 5 2009, 11:28 AM~12914254
> *I GOT A CHEVY 350 WITH EDELBROCK INTAKE HOLLY CARB,, WEN I PUSH ON GAS TO A HIGHER RPM THEN IT STARTS TO DO THE POPPING SOUND THREW MY CARB, IS THIS CAUSED BY 1 OF MY LOBES WORN OUT ON MY CAM SHAFT??
> *


depends
Could be timing but if you havent messed with it in a while and it runs fine otherwise then probably not

Could be worn out valve springs allowing the valves to float at higher RPM, in other words theyre not shutting all the way. Or a valve is bent or heavy deposits of gunk causing it not to close all the way. 

Ive seen lobes get wore down to nearly nothing and still work ok. Just no performance


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## Ragtop Ted

If its missing, maybe the distributor is worn.


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## 64 CRAWLING

ima fuck with the distributer and see wat i come up with, good info guys let me see wats up


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## CoupeDTS

> _Originally posted by 64 CRAWLING_@Feb 6 2009, 11:12 AM~12924906
> *ima fuck with the distributer and see wat i come up with, good info guys let me see wats up
> *


yea check out all the points and such. If it just started happening you know something isnt wore down its more likely something broke. Like a broke valve spring or plug or wire or whatever.


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## 64_EC_STYLE

> _Originally posted by CoupeDevilleDTS_@Feb 5 2009, 02:09 PM~12914634
> *depends
> Could be timing but if you havent messed with it in a while and it runs fine otherwise then probably not
> 
> Could be worn out valve springs allowing the valves to float at higher RPM, in other words theyre not shutting all the way.  Or a valve is bent or heavy deposits of gunk causing it not to close all the way.
> 
> Ive seen lobes get wore down to nearly nothing and still work ok.  Just no performance
> *


co-sign

but need a little more info, have you done anything to the engine lately, 

did you change the cam and not the springs? I've done it and that is sounds like exactly what happened, worn valve springs.

Bad vacuum advance? 

distr. 180 out?

so it runs fine at lower RPM until you step on the gas?? 

I think coupe de ville hit it right


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## 925rider

i lost a few teeth on a timming chain before, pull the dist cap off and see if the rotor is going aroung smooth or if its jumping around. i guess alot of the early 70s 350s lower timming gear was aliminum with nylon teeth. i changed the timming chain and found a few bent valves so i ended up putting heads on it.


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## kandylac

LOOKS LIKE WE ALL AGREE IT'S TIMING RELATED.


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## CoupeDTS

> _Originally posted by kandylac_@Feb 6 2009, 09:11 PM~12930611
> *LOOKS LIKE WE ALL AGREE IT'S TIMING RELATED.
> *


We all agree to rebuild also


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## 64 CRAWLING

> _Originally posted by 64_EC_STYLE_@Feb 6 2009, 09:30 PM~12929980
> *co-sign
> 
> but need a little  more info, have you done anything to the engine lately,
> 
> did you change the cam and not the springs?  I've done it and that is sounds like exactly what happened, worn valve springs.
> 
> Bad vacuum advance?
> 
> distr.  180 out?
> 
> so it runs fine at lower RPM until you step on the gas??
> 
> I think coupe de ville hit it right
> *


yea wen i drive low rpm its good but higher rpm it do the popping threw the carb, i got the bottom half of the motor done, but even before that is was doing it


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## 64_EC_STYLE

> _Originally posted by 64 CRAWLING_@Feb 7 2009, 06:08 PM~12935811
> *yea wen i drive low rpm its good but higher rpm it  do the popping threw the carb, i got the bottom half of the motor done, but even before that is was doing it
> *




assuming that when you say the bottom half was done there is a new cam w/ timing chain and gear set, which leaves the timing(in which we all agree)

I would start with vacuum advance, just for GP, and then change out those valve springs.

In the case that the cam set hasn't been changed out, I would invest in a cam kit with cam, lifters, valve springs and seal for around $300(assuming you do your own work because this would be expensive at a shop for an easy fix)


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## 64 CRAWLING

new timing chain, rear main seal and crank shaft, the cam and lifters still the same


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## 64 CRAWLING

> _Originally posted by 64_EC_STYLE_@Feb 8 2009, 12:46 AM~12938356
> *[/size]
> 
> assuming that when you say the bottom half was done there is a new cam w/ timing chain and gear set, which leaves the timing(in which we all agree)
> 
> I would start with vacuum advance, just for GP, and then change out those valve springs.
> 
> In the case that the cam set hasn't been changed out, I would invest in a cam kit with cam, lifters, valve springs and seal for around $300(assuming you do your own work because this would be expensive at a shop for an easy fix)
> *


yea i guess i have to buy the set and hope that works


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## 64 CRAWLING

yea pulled my valve covers and the left side on the 4th rocker it aint moving at all


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## danp68

> _Originally posted by 64 CRAWLING_@Feb 8 2009, 12:34 PM~12940896
> *new timing chain, rear main seal and crank shaft, the cam and lifters still the same
> *


did you over tighten your rockers? that will do it too(learned that the fist time i rebuilt a small block),other than that it sounds like your timing gears arent lined up right-you can try the distributor but sounds like timing is off via timing chain gears-if you get those off it will open an intake valve during comprssion stroke therefore blowing thru your intake and carb


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## danp68

> _Originally posted by 64 CRAWLING_@Jun 12 2009, 10:22 AM~14169744
> *yea pulled my valve covers and the left side on the 4th rocker it aint moving at all
> *


that is a bad lifter or too short of a lifter rod,that should just make it run like shit(7 cylinders working right) shouldnt cause blow back


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## 64 CRAWLING

yeah it dont feel like it got alote of power but still drives gud though, i struggle to go up a hill though lol


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## cfbtx

> _Originally posted by 64 CRAWLING_@Jun 12 2009, 11:33 AM~14171687
> *yeah it dont feel like it got alote of power but still drives gud though, i struggle to go up a hill though lol
> *


Same problem that I am having with my ht4100


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## 64 CRAWLING

THATS YOUR PROBLEM ITS A HT41OO


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## CADILLACJON

> _Originally posted by 64 CRAWLING_@Jun 14 2009, 02:00 PM~14186078
> *THATS YOUR PROBLEM ITS A HT41OO
> *


lol :roflmao:


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## cfbtx

> _Originally posted by 64 CRAWLING_@Jun 14 2009, 11:00 AM~14186078
> *THATS YOUR PROBLEM ITS A HT41OO
> *


very true but soon to be a 5.7 350 :0
:biggrin:


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## 64 CRAWLING

that will solve the problem then lol :biggrin:


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## NY-BOSSMAN

i know this is an old topic but ive had this problem and it turned out to be the float level in the carb


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## wingnut

probley timming


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## [email protected]

x2


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## 64 CRAWLING

if i turm my distribiter where pose to be at it dont run right so it turned way out of place to run right since 1 of my rockers are dead so it runs like its a 7 or 6 cylinder


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