Progress Thread Komo's 1990 GT - Parts Gathering Purgatory

I think the real question is why does Trick Flow provide 3/8 studs with the heads if they are threaded for 7/16?

Now I gotta spend money on new 7/16 studs.

Yeah but, do you [really]?

I mean... If you got solid lifter, steep cam ramps, and stupid high spring pressure you could easily justify the expense.

In your situation... It's a [nice to have].
 
Yeah but, do you [really]?

I mean... If you got solid lifter, steep cam ramps, and stupid high spring pressure you could easily justify the expense.

In your situation... It's a [nice to have].
Ya just since my last post I’ve been researching more and sounds like (as you mention) I don’t need the 7/16 setup for what I’m going for.

Also sounds like those scorpion 1019’s I ordered then cancelled work well with stock valve covers. Decisions decisions.

I did write Harland sharp asking what their rockers are, 3/8 or 7/16 because it doesn’t say on their website. Most likely 7/16 is my guess.
 
They probably provide the 3/8” studs to knock $30 off the price of the head. Id also say most folks probably have 3/8” rockers because they don’t have a solid roller with stout springs.
 
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If anyone is wondering, the Harland Sharp rockers can be made with either 3/8 or 7/16 trunnions, you just need to specify when you order. So, to save some money (or recoup costs for the higher priced Harland Sharp rockers by not buying 7/16 rocker studs) i will probably go with Harland Sharp TW head specific rockers in 3/8".
 
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Since I have to do my drivers side door pin replacements once i get back into my house/garage... i've been trying to find good videos about it. This is the best one i can find so far... he does a really good job of walking you through every step and not being like typical YouTubers where its like, "ok do this" and then it cuts to when its all done:


View: https://www.youtube.com/watch?v=98xnQ7rU7iM


So for anyone else that needs to do door pins, this could be helpful.
 
Another week, another job of removing and cleaning my spark plug.

However, oil level was still showing full this time around. I expected it to be a little low. Interesting.

I did borescope the cylinder when i had the plug out. Top of piston looks good still, a little 'wet' looking but overall very clean considering. However, swiveling the borescope upwards to look at the cylinder head and valves. Still super crusty. Maybe it is the valve stem seals... I have just shy of 500 miles on this R&P oil change, with about 50 miles with the Engine Restore product as well. Also running my second tank of Redline SI-1.

Will keep monitoring the oil level as consumption seems to have dipped slightly?

Was going to do a compression check while at work today but forgot i left my compression tester in my 4runner.
 
I swapped out my metal casing fuel filter for my supercharger blow-by vent line with a clear casing one just so i can see whats going on.

I looked inside the existing metal filter and did not see any signs of oil vapors nor did it smell at all. So i'll keep it in the car in case the clear one doesn't work out.

Fox Pressure Line.webp

This is the line i need to move to the inlet elbow (I already bought the "L" fitting for that job), but for now it stays here.

I also have a J&L Oil Separator ready to install on the PCV side, just need to find a good mounting point for the can.
 
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Damn, so I gave the ol gal a solid pull in second gear and she completely fell flat again at around 5,500 rpm’s, just like the time way before. It was suggested I needed to close up my plug gap, and I did after that first time. I went from .054 down to around .040-.043 (based on a non super accurate circle gap tools).

Think I need to close them up even more? I’m surprised because I’ve only ever seen 3psi on the boost gauge but I also can’t rev it out to max boost because of this issue.

Should I close them up to like .035 or something? Odd that it cuts out at the exact same RPM even with closer plug gaps… I would figure it would give me a little more RPM before cutting out.
 
Ok thanks you guys. I picked up the Amazon GearRoll one @Noobz347 linked (placed order before I saw your post @AeroCoupe ).

I know I know it’s AI, but ChatGPT said I should go down to .030 with my setup… is that too close or is this a trial and error type situation? Passenger plugs especially #1 is kind of a pain to swap out.
 
Ok thanks you guys. I picked up the Amazon GearRoll one @Noobz347 linked (placed order before I saw your post @AeroCoupe ).

I know I know it’s AI, but ChatGPT said I should go down to .030 with my setup… is that too close or is this a trial and error type situation? Passenger plugs especially #1 is kind of a pain to swap out.

Start there and run it a while.
 
I dunno. 3psi seems pretty low for spark blowout. Makes me wonder if something else is the culprit. When I got the entry level 5psi kit the instructions specified to "install new factory heat range plugs as specified by the manufacture". I read that as factory gap though it does leave room for interpretation. I ran it with the plugs gapped at .054 at 5psi with no issue. Eventually upgrading to 10 psi I did close up the gap to .045 because it seemed like a good idea. No issues. Ford coil, cap & rotor, good plug wires.

I guess its easy enough to try and at least rule out though. I can't remember, do you have a fuel pressure guage on there? I'd want to make sure the FMU is working correctly also.
 
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I dunno. 3psi seems pretty low for spark blowout. Makes me wonder if something else is the culprit. When I got the entry level 5psi kit the instructions specified to "install new factory heat range plugs as specified by the manufacture". I read that as factory gap though it does leave room for interpretation. I ran it with the plugs gapped at .054 at 5psi with no issue. Eventually upgrading to 10 psi I did close up the gap to .045 because it seemed like a good idea. No issues. Ford coil, cap & rotor, good plug wires.

I guess it’s easy enough to try and at least rule out though. I can't remember, do you have a fuel pressure guage on there? I'd want to make sure the FMU is working correctly also.
I say 3psi because that’s the most I’ve seen my boost gauge go up to, however, once I get up into the RPM higher and higher I’m no longer focusing on my boost gauge, but the road. So maybe it’s higher. I should film it next time.

So one things that Is odd to my novice brain: It cutout at the same rpm (I should go back and find my original post about this when it happened the first time and verify) with plugs gapped at .054 and .043-ish. Shouldn’t have closing up the gap allowed me rev the engine up at least a little higher?

I will get a fuel gauge (at some point) and try taking it to my cowl like I’ve seen some people do.

This is so frustrating I’m having all these issues and can’t f*ckin work on the car. Aargh!
 
I say 3psi because that’s the most I’ve seen my boost gauge go up to, however, once I get up into the RPM higher and higher I’m no longer focusing on my boost gauge, but the road. So maybe it’s higher. I should film it next time.
Right. Just mentioning I didn't have any spark issues at 5-7 psi with a .054 gap. Not saying it isn't your issue, but I had none at that range.


So one things that Is odd to my novice brain: It cutout at the same rpm (I should go back and find my original post about this when it happened the first time and verify) with plugs gapped at .054 and .043-ish. Shouldn’t have closing up the gap allowed me rev the engine up at least a little higher?

I will get a fuel gauge (at some point) and try taking it to my cowl like I’ve seen some people do.
Yeah, you could rent one. Just a standard fuel pressure guage (tool). Then if you have a hand pump vacuum / pressure tool https://www.harborfreight you can at least verify your FMU is working correctly. They come in handy for lots of things like bleeding brakes.

-install FP guage to fuel rail Schrader valve
-remove vacuum line from FMU and plug hose
-set hand pump to pressure and connect to FMU nipple
-start car and make sure no fuel leaks
-hold RPMs up a little so it wont bog down when you bump up the FP with the FMU
-observe FP guage with car running
-pump 5 psi into FMU with hand pump (this simulates boost pressure)
-note FP increase as you apply pressure. It should go up from base FP to 60 or more. At 10 psi it will be around 100 psi with the disc your running for 19lb injectors.
-release pressue from pump as soon as you see it operating correctly or you'll flood the engine.

Just something pretty easy to test. If it passes that test I'd take it for a ride and see what the guage does when you experience the issue. If it looks good move onto spark.

Its just all about eliminating things one by one. Eventually you'll find it. I'm just mentioning to check the FMU becasue if it isn't working it could mean bad things happening by running lean. Probably worth a look see. Your issue is either spark or fuel, so rule out the most detrimental possibility first IMO.


This is so frustrating I’m having all these issues and can’t f*ckin work on the car. Aargh!
You'll get it. One thing at a time.
 
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Right. Just mentioning I didn't have any spark issues at 5-7 psi with a .054 gap. Not saying it isn't your issue, but I had none at that range.



Yeah, you could rent one. Just a standard fuel pressure guage (tool). Then if you have a hand pump vacuum / pressure tool https://www.harborfreight you can at least verify your FMU is working correctly. They come in handy for lots of things like bleeding brakes.

-install FP guage to fuel rail Schrader valve
-remove vacuum line from FMU and plug hose
-set hand pump to pressure and connect to FMU nipple
-start car and make sure no fuel leaks
-hold RPMs up a little so it wont bog down when you bump up the FP with the FMU
-observe FP guage with car running
-pump 5 psi into FMU with hand pump (this simulates boost pressure)
-note FP increase as you apply pressure. It should go up from base FP to 60 or more. At 10 psi it will be around 100 psi with the disc your running for 19lb injectors.
-release pressue from pump as soon as you see it operating correctly or you'll flood the engine.

Just something pretty easy to test. If it passes that test I'd take it for a ride and see what the guage does when you experience the issue. If it looks good move onto spark.

Its just all about eliminating things one by one. Eventually you'll find it. I'm just mentioning to check the FMU becasue if it isn't working it could mean bad things happening by running lean. Probably worth a look see. Your issue is either spark or fuel, so rule out the most detrimental possibility first IMO.



You'll get it. One thing at a time.
I will look into fuel when time allows. (Need to buy mechanical gauge). Something seems fishy that the car falls flat at the same RPM with tighter plug gap, so I’m skeptical it’s spark plug related. And as you said this kit is for a stock 5.0 which mine is (except exhaust) so it should be fine with stock gapped plugs.

Got a couple different things I need to diagnose. In the meantime I just won’t rev it out.

Also, reaaaaally need to get my wideband bung welded in so I can screw in my sensor. Been free ballin the AFR this whole time.

Edit: I went back through my thread and found the post where the car fell flat previously. I said “5k rpm” then… now it’s closer to 5,500rpm with the smaller plug gap. I dunno something still seems off. Will diagnose fuel pressure but also close plug gap a little more.
 
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I don't mean to just jump in here but ^^^that^^^ could be an important tool to diagnose this issue.
I know I know. I normally don’t go past 3,500 rpm’s when driving just due to my ‘other’ many issues but I get it, need to get this done asap. I kind of haven’t made it a priority because I have a stock car (basically) with a supercharger made for a stock car putting out dismal boost figures.