I need some advise with reading The photo below shows bluing on the first few threads Should I be ok or am I supper lean Thanks Sent from my iPhone using The H.A.M.B. mobile app
Not sure what you mean by over heating. My temp gauge reads constant 160 degrees. Sometimes my electric fan doesn't come on. I would like to know what you think is causing the heat. I'm running autolites 764 coppers. Should. I go to a colder plug? Sent from my iPhone using The H.A.M.B. mobile app
Plug reading is tricky. It takes a lot of experience to know what you're looking at. It's not anything like what people popularly think it is, the porcelein color is just one thing, and modern fuels don't react the way they used to. The stock heat range plug is usually perfect or near enough, for most uses. Extended interstate cruising in the summer, a cooler plug is probably indicated. But a grossly mistuned carburetor, with oily fouled plugs, is not a reason to switch heat ranges. This is very common. Wideband o2 sensors aren't being given away yet, but they are worth every cent for carburetor tuning. Still need to look at plugs, but the widebands take a LOT of the guess and by golly out, especially for people who didn't grow up reading plugs. Make sure your ignition and ignition timing & distributor advance is all squared away. A strong, hot spark is required. THEN tune the carburetor, get it dialed in, the idle and cruise circuits, power, transition circuits, etc, are all different and will be evident in a different part of the plug. For example, wide open throttle mixture is observed way down inside the plug, where the plug shell transitions to the porcelein. Need a strong light and magnifier. The ground strap shows heat range, and believe it or not, ignition timing and advance. This takes experience. Going too lean under load will nuke pistons, so getting this right is important.
the plug is too long and in the chamber , check the head number and see what the proper plug reach it should have , if it was too lean it would be ash white with no brown color , and this includes the strap .
Heads 90's explore GT40 Stock autolite 764 for those heads. Sent from my iPhone using The H.A.M.B. mobile app
That is correct plug for GT40P head that you have . I still say lean , your using injected plug on carbed engine, cool it down a heat range and try it , also richer up the carb a bit
The porcelain on the OP's photo would indicate that the heat range of the plug is acceptable. Colder plug AND richer mix will darken the porcelain quite a bit.
I'm running 3 Stromberg 48s on a early 302 with a tunnel ram. Uncle Max suggested open the Jets up a .001. I took all 3 carbs off and got them ready to go back on tomorrow. Max is the man I don't question any of his opinions. I'll see what happens over the weekend and I'll let you guys know how I made out. I can't believe this site it's full of instant knowledge there is no other place like it. Thanks I threw a couple picture on of my truck. Sent from my iPhone using The H.A.M.B. mobile app
Cool truck - interesting manifold choice to run with those carbs - from a site "The Hot Rod Garage" :heads changed in early '97 - talk about using Autolite 104 instead of 764 w/ .054" gap there is a difference in length of plug - also, NGK TR55 as alternative - the '93-'95 Cobra/explorer GT40 heads were milled to bring it's larger combustion chamber down to size of E7 heads to keep compression up - others say bluing of plug is due to plug itself overheating
I agree 100% even though ur running what it calls for it will react diff to a carb run motor and it looks a little to LAN to me to, jmo hrh Sent from my iPad using The H.A.M.B. mobile app HotRod Harry
The threaded portion of the plug should be transferring the heat to the head. Antiseize should help do that.
I opened up the jets a bit and it looks much better. My next move will be an increase in power valve size. I feel real confident with my idle and mid range it's the WOT that still looks a bit lean. I love the suggestion of anti-seize on the threads to help transfer some heat. It's quick,cheap,and almost effortless. From there I'll try the Autolite #104's. I may be old school and I may be cheap, I've always been a big fan of the Autolite copper plugs. You can keep your $5.00 plugs with the titanium electrode with split ground strap wiz-bang stuff. I think the olé coppers will give you the biggest bang for the buck (No pun intended). Sent from my iPad using The H.A.M.B. mobile app
Hey, Thanks for the thumbs up and info. The Strombergs took a little time to get them March to the same beat but it will idle all day @ 800 rpm now and I have no problem running it on the street. When you hit it,it's instant get-up and go. More so than I have had with any other. Gets a lot of looks too. Sent from my iPad using The H.A.M.B. mobile app
It's always a good idea to use antiseize on spark plugs, especially tapered seat plugs that have a nasty habit of not coming out.
No offense to your uncle, but I don't think carb manufacturers recommend drilling out the jets .001". Drilling may cause the internal passageway to be left with a rougher surface that original and the rougher surface can reduce the flow thru the jet such that even though you made the opening bigger the flow thru the jet may actually be less.
Let me clarify it a little. The good uncle told me to step it up a bit so I did it the Traditional way with a .047 drill bit That's what we're all about isn't it Sent from my iPhone using The H.A.M.B. mobile app
Drilling jets...I think everyone that's fooled with hot rods has done it at least once. Yes from what I can tell it's lean. I would be as worried about black specs on the center porcelain. They mean you are getting things hot enough to flake the top piston ring.
Frenchtown Flyer, You are correct. Even as you know jets are so sensitive to hole finish and hole inlet and exit shape and finish. You can buy jets brand new and send them out to be flowed, (like for injection) and even though they are manufactured by the same company and made with precision equipment, they will flow differently. Lippy
I'm not being a jerk here. Could you explain to me want would sending the jets out to be flowed for a driven show car. Sent from my iPad using The H.A.M.B. mobile app
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