Help--headers glowing red in the daylight

[Type73LT]

Help--headers glowing red in the daylight

I changed the heads to alum and higher flo. I changer the rockers arms from 1.5 to 1.6.
I changed the intake to an RPM AIR GAP.

The hearders got so hot they caught a spark plug wire on fire.

I have procomp alum heads and have champion spark plugs no. 89.

It will not idle and only runs if I goose the throttle. If I wholed it in place it dies out.

Do I need a higher jet size. I have a Holley 670 street avenger carb stock jetting.

Please help!!!!!!

[MuscleRodz]

check your timing

[Ron.in.SoCal]

Are all of them getting red or just one or two? One time I saw a valve get stuck and do that. As soon as it got 'unstuck' the headers did not get as hot...

(Mike is prob right, though - unburned fuel can act like a cutting torch)

[SSMuscle]

check your timing


same thought

[My427stang]

same thought

X3

Advance your timing

[twosaturns]

sounds to me like its running too lean. but of course, check the timing.
what engine? how did you set initial timing?

[critter]

Sounds lean to me.

[MrQuick]

what kinda car are we talking about? have cats?

you got some major vac leaks or a bum carb.

[Type73LT]

It is a 350 sbc bored .060 over

Timing is fine. It runs smooth when running. I had a vacuum leak once and the engine bucked all over so I do not have a leak I believe.

The cam is .485 lift at 1.5 ratio so new lift would be .517.

Car is a 1973 Camaro. No cats. 2.5 inch exhaust. Carb ran fine before the upgrades. Could it be that lean for the upgrades?

Do you think I should try like 4 jet sizes?

[My427stang]

It is a 350 sbc bored .060 over

Timing is fine. It runs smooth when running. I had a vacuum leak once and the engine bucked all over so I do not have a leak I believe.

The cam is .485 lift at 1.5 ratio so new lift would be .517.

Car is a 1973 Camaro. No cats. 2.5 inch exhaust. Carb ran fine before the upgrades. Could it be that lean for the upgrades?

Do you think I should try like 4 jet sizes?

You say timing is fine, but what is the timing set at? and are you sure the balancer didn't move on you and the advance is working properly?

I would be AMAZED if it was jetting, especially if they are hot at idle

I'd triple check the firing order, check with a timing light, and verify TDC

Before you bathe it in fuel with a big jet change (which it shouldn't need) let us know exactly when the headers glow

[ZZ430]

Sounds lean to me too, but of course at idle the jetting has nothing to do with it.

As mentioned, advance the timing and adjust idle mixture screws with a vacuum gauge to get the highest reading.

[68Formula]

Most likely your higher flowing heads also have larger runner volumes. You switched to an AirGap from probably a Performer dual plane? Both changes (and to a small degree the rocker arm change) will probably have less of a vacuum signal at idle, part throttle, and low rpm full throttle operation.

Adjust your carb as stated earlier, adjust the curve so that you can increase your initial without changing your total, and confirm that your rocker arms are adjusted properly.

[Type73LT]

It will only idle for a few seconds and I have to goose the throttle to keep it going. If I hold the pedal steady at say 1500 rpm it again starts to die out and I have to goose the throttle again.

Timing is at 8 degrees with out vacuum hooked to the distributer. I have backed out the idle mixture screws another half turn and it may have help some but still dies idling.

I do not know if these spark plugs are close to what I need....Champion number 89. That is what the counter guy said to try. I asked The company I bought the heads from and procomp and neither would give me a recommended plug heat range to start with. I know I will have to change to shorty plugs because the boots are just to close to the headers. To get the right ones I need to know how close I am now with these 89 plugs.

Should I try a different carb? or just increase the jets first. I have a 780 vac sec card and a 650 dp. Both were set up for the old set up of the engine so if it a jet problem then they too would be wrong.

[My427stang]

Sounds like a possibility of a few things.

1st, how did you adjust your valves? Sounds like maybe you have a tight one or two

2nd - Advance your timing to 14 for now. You really will need to recurve later, but if its a timing issue or a slipped balancer, it'll start idling well and cool right down, then we can figure out whats happening.

If the valves are adjusted correctly, the idle problem then sounds like a bad vacuum leak, I'd pull the carb and look at the imprint on the base gasket, you may find its sucking air

DO NOT do the jets, I know you are itching to do it, but it wont do a thing. It is 100% positively not a jetting problem or a plug problem.

[My427stang]

Also, A Champion 89 is an RC12YC variant, one of the most common plugs for SBC, SBF, BBC, BBF, FE Ford aluminum heads, its a good start for what you are doing

[68Formula]

Pull the plugs and see if they are carbon fouled. Could be why your not able to get it to idle right now. Its going to at least need to idle on it's own so you can make adjustments.

Leave the jets alone for now. Won't do a thing to fix your idle issue. Also, does it look like fuel is coming from the boosters at idle? Blown power valve or throttle blades opening past the transition slot would add too much fuel at idle and make the idle screws useless. You can figure out if you're past the transition slot by hooking up a vacuum gage to the ported spot on the distributor and see if you get a reading.

What's your engine specs? (Compression ratio, displacement, cylinderheads, and camshaft)

Did you spray carb cleaner around the intake base and carburetor base to check for air leaks?

[Type73LT]

OK I found a vacuum leak...well not a leak but dummy me. I took off the power assist hose putting on the spark plug wires and forgot to put the hose back onto the intake. So I also took the idle bleed screws out 2 full turns. It idles smooth now...no goosing the pedal, the choke works fine. Timing is at 10 degrees without the vacuum hose hooked up. It sounds much stronger than it did before even out the exhaust.

BUT THE HEADERS STILL GLOW. Even at idle after 2 minutes they start orange-ing up. So i shut it off not wanting to do more damage then I may have already to the headers.

Again what I changed so far....
Went from 186 fuelie heads with 1.94 values to Procomp 190 heads with 2.02 values same 65cc.

From Weiland stealth intake to RPM Air Gap.

Kept the Holley street avernger 670 carb so far.

From stock 1.5 rockers to 1.6 on a was ,485 lift cam which should be a .517 lift now. and I kept the anti pump up lifters also.

I also switched headers from 30 year old Eagle headers to Summit ceramic coated. That is why I will be switching to shortie/header spark plugs. Just not much room at the bends.

When I adjusted the lifters I did it by the book. I by hand turned the nut until the new push rods stopped turning in my other fingers. turning the motor to keep them on the base circle. Then I went back and took them all 1/3 turn more. Which will have them a little on the loose side for more rpm.

Still need ideas why all the header tube start to glow. If I raise the rpm the glow faster. At idle they start at about 2 minutes.

[DynoDon]

You need a bunch more timing. You are not only putting unburned fuel through the exhaust that is igniting in the headers, you are also transferring much more heat to the cylinder walls because it is burning long after piston is heading back down.
Start at 14-16 degrees and see if that doesn't help.

[Nessumsar]

Your initial timing is still too low. Try what 427stang said and get it to 14*-16*. I have my 383 set at 18 initial, 36 mechanical, plus vacuum.

Maybe your coil is dying?

Although I don't believe this is all of your problem...

edit: Don posted as I was typing.

[Type73LT]

I will try more timing. I have a new distributor and 6al ready to put in but I want to make sure everything I have changed is working first. I do not want to make so many changes and something is not right with a list so long.

I did not pull the motor and only turned it over to adjust the rockers with no plugs in. I could have turned it free hand almost. I never touched the Rattler balancer other than the center bolt.

I have been using a Ignitor 2 pick up and a Mallory Voltmaster coil. I once had a GEO Metro. 3 clynder and a 5 speed. It started bucking on the way home. I did some testing and guessed the coil was going. I had a Accel yellow super stock coil from the camaro from before the Voltmaster and put it on the Metro. Never a problem again. I put over 300,000 miles on it and it still did not burn oil and would spin the tires thru 2 gear. I broke down and want AC so I traded it in.

[DynoDon]

That Mallory Voltmaster may have more resistance than we like to see with our Ignitor II as well, possibly creating a weak, late spark - depending on the model. The .75ohm would be fine.

[Gitter Dun]

You need a bunch more timing. You are not only putting unburned fuel through the exhaust that is igniting in the headers, you are also transferring much more heat to the cylinder walls because it is burning long after piston is heading back down.
Start at 14-16 degrees and see if that doesn't help.

X 2, I had nearly same set up and initial timing was 14 degrees.

[Pro Stock]

Timing not advanced enough at Idle can be one cause and to rich of an idle due to something like a blown power valve or other carb problem not related to manifold signal. An engine that is way to fat at idle and part throttle can give you the impression that it is lean (i.e. red hot headers) the headers can glow red hot when the engine is super rich because all of the fuel isn't burned during the combustion prosess and continues to burn in the pipe causing them to glow red. We have done this intentially for magazine shoots on the dyno for the dramatic effect, that alone can be your problem but combine it with not enough timing and watch out!

Dale

[kochevy67]

Lean is mean, check the fuel.

[Charley Lillard]

LOL...Don't post again until you can tell us you have 15 degrees advance...

[Type73LT]

Well I advanced the timing to the end of the tab. I am down to 2 tubes glowing at idle. 3 and 6. In the am I will try turning the idle screws in because I have them out 2 full turns now and see what that does. Then try the engine at a higher rpm. Still have not had it run long enough for the thermostat to open.

Maybe just a little more timing?

[John Wright]

Well I advanced the timing to the end of the tab. I am down to 2 tubes glowing at idle. 3 and 6. Sounds like you are gaining on it.....keep after it.

[twosaturns]

leave em glowing, it looks cool, lol...

[406 Q-ship]

leave em glowing, it looks cool, lol...

The ceramic caoting might have something to say about that!

You did nothing with the Cam other than the rocker arms? I am wondering about cam timing.

[68Formula]

Hhhmmm, 3 and 6 are consecutive in the firing sequence. Wonder if that means anything. Like something causing those two cylinders to be lean.

So, did you check your firing order? I remember one time, long story short I had double-checked everything, then a helper disconnected two to do something else, and then mixed them up. Drove me nuts for a bit because I "knew" the order was correct since I had already done the double check.

Also, try hooking the timing light up to #6. Since the firing is 180° out you should see the same value on #6 as #1 on the balancer. If not something is wrong like the timing is bouncing around.

[Type73LT]

OK. I have the stock timing chain cover so it does not go high enough. It seems fine now as far as the glowing goes. Timing is 1/2 inch off the scale and it seems to like it.

A side note anyone working on the water pump at least on a sbc put sealer on the 4 bolts that hold on the water pump. Since it was finally able to run and heat the engine up I guess the pressure was enough that I found a small leak from one of the bolt holes. I will fix that up and put in the new distributor and 6 AL.
I will also get a timing tape to put on the balancer so I can be more accurate on the timing.

Thanks for all the ideas people.

[claytonisbob]

You can probably do a little math on the balancer using a tape measure and make some timing marks with a white marker to give you an idea of where you may be.

[John Wright]

Have you checked the mechanical advance weights in the dizzy to make sure they are returning after advancing?....I've seen them stick and they will give you a fit trying to get the timing straightened out.

[John Wright]

You can probably do a little math on the balancer using a tape measure and make some timing marks with a white marker to give you an idea of where you may be.

Wrap a tapeline around the balancer....take that measurement and divide by 360, that will give you a measurement for each degree. I took a hack saw and made a cut similar to the TDC mark at 36° and painted it with a metallic silver paint, so that it shows up nice with the timing light. I use an adjustable timing light and place the timing light on 36° and adjuct the dizzy so that the 36° mark sits on zero on the timing tab.

[rrunner68]

Get a good timing gun that is adjustable.

[John Wright]

an example:
8" balancer should measure approximately (8" x 3.14) = 25.12" roughly 25 1/8"

Take 25.12 and divide by 360° to get .06978" per degree.

Take that measurement and multiply by 36° and you will have a measurement to mark on your balancer for 36°(2.512") from the zero mark.

[osdmike]

OK I found a vacuum leak...well not a leak but dummy me. I took off the power assist hose putting on the spark plug wires and forgot to put the hose back onto the intake. So I also took the idle bleed screws out 2 full turns. It idles smooth now...no goosing the pedal, the choke works fine...........


Do You still have the bleed screws out 2 full turns?
If it runs to lean,You may try to step up the primary jets 1 or 2 steps and then readjust the bleed screws.

------------