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Discussion Starter #1
Im trying to breakin my new 355 I built.

9.5:1 CR
World S/R torquers
262 VooDoo cam
750 Holley
Performer RPM intake

Anyway, I got it fired and was maintaining 2500 to 3000 rpm to break in the cam and only the left bank header began to glow so I shut it down after only 3min. The right bank seems fine. Timing was at 35 total, I tried advancing and got up to 38 degrees but header again started to glow after only 2 min. I rebuilt the Holley so I set my mixture screws 2 turns out to start out. I checked for vacuum leaks and found none. I just cant figure out why just the left bank is getting so hot.

Another question:
I know the new cam cant take much cranking so I tried to get everything right for start up but I ended up cranking it for about a total of 20 revolutions before I diagnosed a bad coil. Now it starts well and I have run it twice at 2500-3000 rpm for just a few minutes at a time like I talked about above. Do you think I have damaged my new cam already? or was the moly assembly lube on the lobes enough to protect it for those 20 revolutions?
 

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Im trying to breakin my new 355 I built.

9.5:1 CR
World S/R torquers
262 VooDoo cam
750 Holley
Performer RPM intake

Anyway, I got it fired and was maintaining 2500 to 3000 rpm to break in the cam and only the left bank header began to glow so I shut it down after only 3min. The right bank seems fine. Timing was at 35 total, I tried advancing and got up to 38 degrees but header again started to glow after only 2 min. I rebuilt the Holley so I set my mixture screws 2 turns out to start out. I checked for vacuum leaks and found none. I just cant figure out why just the left bank is getting so hot.

Another question:
I know the new cam cant take much cranking so I tried to get everything right for start up but I ended up cranking it for about a total of 20 revolutions before I diagnosed a bad coil. Now it starts well and I have run it twice at 2500-3000 rpm for just a few minutes at a time like I talked about above. Do you think I have damaged my new cam already? or was the moly assembly lube on the lobes enough to protect it for those 20 revolutions?
Give it as much initial as you can without going over the 38 total. I run around 20 initial and 18 mechanical. Retarded timing or a lean condition can cause the header glow. I have never had to put a fan on one, but you can put a shop fan by the radiator also to help it. I always had mine ready and cranked them and either high idled them or drove them.

Only time will tell you about the cam, but I wouldn't sweat it as it's already done either way. Oh the joys of a roller cam.:D

Good luck with it.
 

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Just going thru everything. How did you go about adjusting the valves? Have you noticed the squirters in the carb working properly? Assume you have the float levels set on carb?
 

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Discussion Starter #4
Just going thru everything. How did you go about adjusting the valves? Have you noticed the squirters in the carb working properly? Assume you have the float levels set on carb?
The squirters are working fine, I just put in a new accelerator pump. I adjusted the valves to zero lash (not mistaken for bottomed out lifer) + 1/2 turn. The floats are set now as the rebuild instructions stated with that little paper ruler. can I set the floats with it at 2000rpm during break in or does it have to be at idle?
 

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The squirters are working fine, I just put in a new accelerator pump. I adjusted the valves to zero lash (not mistaken for bottomed out lifer) + 1/2 turn. The floats are set now as the rebuild instructions stated with that little paper ruler. can I set the floats with it at 2000rpm during break in or does it have to be at idle?
Set the floats at idle. Squirters won't be the problem.
 

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You can idle it to set initial timing(have everything ready as in tools and light). Also do a quick float set if need be and then go back to the high idle, varying throttle so as to splash more oil on the lobes.

Where did the carb come from?
 

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Discussion Starter #9
You can idle it to set initial timing(have everything ready as in tools and light). Also do a quick float set if need be and then go back to the high idle, varying throttle so as to splash more oil on the lobes.

Where did the carb come from?
Ok Ill go give it a shot. The carb I got off a guy around 2005. I used to run it too on my 406. Ran good but it sat for a few years so I rebuilt it last week before sticking it on this engine.
 

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Discussion Starter #10 (Edited)
Well I tried to idle it to set the floats and it wont idle. If i bring the rpm down to around 1500 it dies and makes a little poof through the carb. Crank it back up and it runs for a few seconds and dies. Even for the few seconds that it runs that left bank header starts to smoke. I sprayed the intake on that side to check for leaks and no raise in rpm. I wonder if the intake weren't meeting the heads on the bottom of the port it could have a vac leak, but in the valley where I couldnt detect it. But I checked the plugs and they have a nice color not like they would be if it were too lean. Also I hear a ticking noise, sounds like an exhaust leak but I couldnt find one maybe I should go through my valve adjustment again.

All this cranking, I might as well go ahead and order a new cam. geez.:beer: Im goin to the store.
 

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Is there anyway you can borrow another carb to try out? Also your certain the cam is in correctly, (my did just had his in 180 off and it ran) but got extremely hot fast. I would recheck valves and go thru carb or switch it.
 

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Remove the float bowls and turn them upside down. Float should be approximately centered in the bowl. This should be plenty close enough to get you started. Glowing headers would indicate a lean condition, so as long as the floats are on the high side they won't cause it to be lean. What oil are you using? Does it contain zinc or did you use an additive? If you have zinc in the oil your cam is more than likely fine.
 

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When you invert the fuel bowl the float should be parallel to the top of the bowl which is now the bottom because it's inverted. The float will be closer to the top of the bowl.
 

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Ive read this post before, but Im pretty sure my timing plenty advanced, Ive got 38* total and I would think timing would effect both banks. I still cant figure out why only the left bank glows.
I am with you as timing(retarded) should cause both sides. A lean condition can cause one side.

While it's running hold your hand over the carb as to not quiet choke it completely. This will cut off the air flow and richen it up. Keep your hand there and watch the exhaust and it should quit glowing. If and when it does then you know for sure it was lean.
 

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If its a dual plane intake and it has a plenum divider cast into it that runs all the way to the top of the carb mounting base, would it be possible that one side of the carb is running lean? Not sure what carb youre using, but assuming its a holley try setting the idle screws at 1 1/2 turns out to start. Also if im correct in my thinking, in a dual plane the right side feeds the left bank and vise versa.

just throwing ideas out there...
 

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If its a dual plane intake and it has a plenum divider cast into it that runs all the way to the top of the carb mounting base, would it be possible that one side of the carb is running lean? Not sure what carb youre using, but assuming its a holley try setting the idle screws at 1 1/2 turns out to start. Also if im correct in my thinking, in a dual plane the right side feeds the left bank and vise versa.

just throwing ideas out there...
Dual plane or single plane can run lean on one side. Could be the main jet or passage is partially clogged. By choking it down the header will stop glowing if it indeed is a lean condition which it seems to be.
 

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Discussion Starter #19
If its a dual plane intake and it has a plenum divider cast into it that runs all the way to the top of the carb mounting base, would it be possible that one side of the carb is running lean? Not sure what carb youre using, but assuming its a holley try setting the idle screws at 1 1/2 turns out to start. Also if im correct in my thinking, in a dual plane the right side feeds the left bank and vise versa.

just throwing ideas out there...
I thought about an intake leak but my intake is dual plane so it does have a divider but one side feeds the inner 4 cyls (4,6,3,5) and the other side feeds the outers (2,8,1,7) so I dont think thats it either. My carb is a Holley 4160 and I did start out at 1 1/2 turns, so far I have taken it to 2 1/4 turns out and it does not seem to help.

sbc1320, I will try that I know my floats are not set correctly yet so it still could be a lean condition. I was in the process of setting floats yesterday and while I had the plug out it stalled and backfired and caught on fire:eek: so I called it a day. I try it again soon and let you know how it goes. I was also going to remove the carb and blow out the jets and passages again.

Ive been researching and I have read some guys taking total timing all the way to 50* during a break in. Seems like alot to me, but maybe.
 
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