If the valves are maladjusted, the explosion could be going straight into the exhaust.

So, you only have the hot cam, stock push rods & lifters, correct? What rockers are you using? Which springs?

 

The hot cam setup was with the 350ci. Now I have a solid roller 383 so no stock internal parts.

Here is some of the specs from my website

383 ci LT4 stroker with forged internals, 12:1 compression, Ported & polished LT4 heads, fully ported LT4 intake, custom solid roller cam 243/243 .572/.572, Pro Magnum 1.6 rockers, ATI aluminum underdrive crank balancer, Canton 7qt. oil pan, lHooker long tube headers, Custom dual 3" exhaust w/electric cutouts to bypass stock mufflers, Canton oil pan, 58 mm throttle body, Delphi/Lucas 42lbs injectors, Holly AFPR, Racetronix GSS340M Fuel Pump Kit,

 

I swapped injector 5 with 1 and the problem did not follow. It looks like the next thing is valve adjustment.

 

I did the valve adjustment and found no surprises. I also found a spreadsheet with the exhaust temperatures recorded using my temp gun and back with the 350 ci engine and it was showing #5 about 100 degrees hotter than the rest. Back then #4 and #6 was not as hot as they are now. I really don't see a point in doing a compression check to check for a bent valve. It idles pretty good considering.

To bad I have the most unique problem in the world that no one can figure out.

 

this is going to seem silly but it is possible that teh cam is a tooth off?

 

Did you pull some plugs and check piston position with regards to overlap while you were doing the lash?

 

No I did not. It seems like the problem is not mechanical because the problem appears to have existed with a totally different engine. I am think of getting a 95 PCM from a friend and try that.

 

I had a promlem like yours because my fuel pressure was to low so i just turned the fuel pressure up a couple notches, if a your running lean headers get hot a lot quicker.

 

Engine Compression Test

1 - 245 psi
3 - 235 psi
5 - 250 psi
7 - 245 psi

2 - 250 psi
4 - 260 psi
6 - 240 psi
8 - 240 psi

Leak down test next

 

I don't have the real equipment for the leak down test but what I did was pump up the compression tester and let it sit for a half an hour. I saw a 5 psi change on the 3 cylinders I tested. Two of which were the ones that were glowing at idle. I don't see a mechancal problem. Does anyone think there is a valve or ring problem now?

 

When I first built my 350 I noticed my headers got nice and pink.... didn't know why and I was running a carb with the stock distributor bottom... which had locked out timing so I didn't get any advace over the initial timing. As soon as I replaced the distributor with a mechanical one to give me my advance, problem was gone. I'm thinking you have a timing issue as well... not that I helped that much. lol Oh, and if you have run with the headers glowing for over 2hrs or so... kiss that ceramic coat goodbye...

 

Then you'd burn your lips!!! I thought ceramic compounds are good on most brand name headers, aren't they?

 

Looks like the "leak down" test proves nothing. I will have to find the real equipment and do the test.

 

I got the real leak down test equipment today.

LEAK DOWN TEST
According to the gauge
70-100% is high
40-70% is moderate
0-40% is low

Remember 4 and 6 were glowing
#2 indicated 15%
#4 indicated 17%
#6 indicated 22%

 

I did a better job this time finding the sweet spot for valve closure. Again interesting...

#2 indicated 10%, air escaping through oil filler cap
#4 indicated 12%, I hear bubbling from the radiator cap
#6 indicated 12%, air escaping through oil filler cap
#8 indicated 16%, air escaping through oil filler cap

I hope I don't have a cracked block because the head gaskets have about 1000 miles on them and the heads were resurfaced. I would not be surprised if the engine shop did not check for that.

 

eric,

sounds like a head gasket.. not a cracked block or you would be seriously pressureizing the coolant system at about all times.. head gaskets may not always leak when heated up, just may be at certain point of temperature or engine load. and it may not be blown at all, just not sealing 100%.

what is the LSA on that cam, it is a good sized cam and with a solid roller once the cam lobe gets past the soft opening it ramps very quickly creating a larger overlap which may very well be leading to your glowing header condition. too much and the raw fuel lights off in the primaries during overlap.

have you checked the lash on the cylinders that glow against the cylinders that don't? check it hot and cold and see what the variance is.

what ignition are you using? pure opti? ltcc? delteq?

what advance is ground into the camshaft? is it +4 or zero? and what timing set? meziere with double roller adjustable? or LT4 extreme duty?

it may not be a timing issue in the PCM but rather in the cam timing.. remember that ift he cam timing is off.....so is your ignition timing as it is based of cam location. are you still using the crank position sensor for the 96 or have you disabled it? answer these questions and lets see what we can figure out.. but if I had to guess.. your cam is off or perhaps the ground in advance or lack there of was not taken into consideration. remember with a distributor your ignition timing is set with a timing light in reference to crankshaft position.. on our cars.. it is all taken into consideration that the cam is in time with the crank.. if it isn't it is difficult to know if the timing advance you see in LT1 edit is actually the correct crank degree of timing.

Chris