That launch photo is rad... glad to see you're still enjoying the 40... even if you are still wrestling with the V8.
Build The Clustertruck Rides Again - Refurbishing a 1975 Chevota
- Thread starter RWBeringer4x4
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- #1,882
Thanks! Basically the highlight of my wheeling career! I’m glad someone caught it on camera.
In the V8’s defense, most of its issues are likely self-inflicted/assembly errors. It has been fairly forgiving, given the circumstances. Really the ONLY major issue I’ve had are the intake gaskets. It’s just unfortunately that it’s sort of a PITA job when they fail…
your statement presumes that Chevrolet controlled the tolerances. There's a second reason for the thicker gasket that's detailed next.
You kind of answered your own question, engines love cold, dense air - heating the air going into the motor reduces your power. The point of the EGR was to more quickly warm up the motor to reduce emissions (after all, the longer the motor runs rich, the worse the emissions) the problem is it doesn't shut off. GM didn't really care that it would hurt hp because their goal was emission reduction. Fact is most new, aftermarket intakes have no provision for the EGR system.
I hate to say it but a rebuild is in your future. 1 looks okay, 2 a bit rich, 3 is oil fouled, 4 is water fouled (which is kind of weird), 7 looks great, 8 is starting to oil foul. 4 being water fouled is weird because the water cross overs are on 1 and 2, 7 and 8. Why I say need rebuild? because the only way 4 got water is either through a cracked head or crack liner....
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- #1,885
I guess we’ll see. If that’s true, I’ll probably sell it. If I’ve got to rebuild my engine every 3000 miles I can’t afford this hobby. Haven’t got the time or interest in going down that road again that quickly. It’ll get a compression test at least before I put it back together.
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- #1,886
For posterity - Cold Compression, WOT:
1 - 159
3 - 165 (oil fouled)
5 - 152
7 - 156
2 - 154
4 - 153 (ash/water fouled)
6 - 152
8 - 150
I know this wouldn’t necessarily diagnose a cracked head, but got an 8.5:1 compression engine I’m happy with that spread…
1 - 159
3 - 165 (oil fouled)
5 - 152
7 - 156
2 - 154
4 - 153 (ash/water fouled)
6 - 152
8 - 150
I know this wouldn’t necessarily diagnose a cracked head, but got an 8.5:1 compression engine I’m happy with that spread…
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- #1,887
Another thing I’ve noticed is that, even with the throttle cable pretty tight, I don’t have the ability to get all the way to wide-open throttle. Even with the gas pedal to the floor, the cable only pulls the carburetor about 3/4 open, which is just barely cracking the secondaries.
This would have been the case from “day 1” as I’ve changed nothing (or very little) in that geometry with the intake swap. I think it’s an issue with the pivot point at the gas pedal. I need more pedal throw before I hit the floor, which might be a little challengine since the gas pedal already sits pretty high. I’m going to need to brush up on my geometry.
This would have been the case from “day 1” as I’ve changed nothing (or very little) in that geometry with the intake swap. I think it’s an issue with the pivot point at the gas pedal. I need more pedal throw before I hit the floor, which might be a little challengine since the gas pedal already sits pretty high. I’m going to need to brush up on my geometry.
Break in is the most important time in an engine life. 90% of wear happens at start up before oil reaches all the working surfaces.
I figured you had low miles on it. I remember it wasn't that long ago since you bought it, because you bought the same crate engine I did. The only difference is I bought mine in the mid 90's when they were $1100. It still runs great. Looking at your #4 plug and a plug reader chart it looks like it could be oil contamination. I agree with you, it's probably from sucking oil in from the lifter valley because of the failed gasket. #3 cylinder was leaking worse than #4. I'd put a new intake gasket, plugs and wires on it.
You know which gasket I'd run. When it comes to plugs and oil filters, my go to is genuine GM, AC/Delco. I'm a little finicky on my plug wires. I like to cut my own and run them under the exhaust manifolds. I think i use MSD. That way it's easy to remove the valve covers without any interference and the engine looks cleaner.
You know which gasket I'd run. When it comes to plugs and oil filters, my go to is genuine GM, AC/Delco. I'm a little finicky on my plug wires. I like to cut my own and run them under the exhaust manifolds. I think i use MSD. That way it's easy to remove the valve covers without any interference and the engine looks cleaner.
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If you can attach the throttle cable somewhere closer to the butterfly (pivot) shaft of the carb, it will change the ratio in your favor also.
Edit, I just looked at your photos in post 1862 and it seems like you are already mounted in the lower hole on the carburetor, but you do have a ton of cable slack...
Edit, I just looked at your photos in post 1862 and it seems like you are already mounted in the lower hole on the carburetor, but you do have a ton of cable slack...
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- #1,891
Yeah, I don’t remember seeing any aftermarket throttle linkage connectors for quadrajets. I think I need to figure out how to get more “throw” from the same pedal travel. My gas pedal is already booger welded together by the previous owner so I’m not opposed to modifying it. I just need to think about the geometry as to how I’d basically get it to start from the same position, but “throw” farther through the travel.
A greater distance from the hinge to the cable attachment at the pedal will accomplish that also, but you will likely have to raise the location it passes through the firewall
Pics of the pedal arm and cable attachment under the dash?
I have found the stock length pedal and arm works well for an LS or a qjet if the cable is attached at the end of the pedal arm, no mods needed.
Maybe yours was shortened?
Pics of the pedal arm and cable attachment under the dash?
I have found the stock length pedal and arm works well for an LS or a qjet if the cable is attached at the end of the pedal arm, no mods needed.
Maybe yours was shortened?
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- #1,893
That’s about the same conclusion I came to. Needs to be mounted higher, and farther from the hinge. Mine was definitely shortened, I’ll try to grab a picture of it tomorrow.
I had this same issue on the quadrajet. I always figured it needed a different bell crank. It was n my list, then I found an LS. Problem solved.
All silliness aside, I was searching for a different bell crank(?) to get the right amount of travel from the LC pedal. I don’t think it’s naturally there.
All silliness aside, I was searching for a different bell crank(?) to get the right amount of travel from the LC pedal. I don’t think it’s naturally there.
the compression test narrows it down to finding where the water is coming in on number 4. They are notorious for cracking heads above the combustion chamber on the exhaust port - given the low miles, Rislone really is a thing - also not driving a new motor is almost harder on a motor then running them for 100k - Illustrated best with a 472 Cadillac motor I had. It was in a flat bottom jet - you know, one of those stupid things you own to make a lot of noise for 3 or 4 times a year (living in the PNW really limits the boat time). It would barely get the rings broke in before it'd park again for the winter - first time I ever considered non-coated rings. During the winter, condensation would pool in the valley - so the first run always got you that great milkshake look. Once it had a few heat cycles it was fine - but because of its low use, it really didn't last that long before someone drove over the crank (which is as bad as it sounds when that motor is in a boat). You could also have weeping head gaskets - again, for the same reason, they never got settled in due to the low miles....
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- #1,896
Here’s a shot of my pedal, vs what I think it probably is supposed to look like (courtesy of BTB’s website). Interestingly enough, it’s classified as a 78-84 assembly (based on the bracket shape). Either way, it looks like the top inch or so of the rod (plus the large blade off the left hand side) is missing, which probably explains the problem. I routed my cable through a sheet of aluminum I used to patch the original linkage hole but I can see how getting up a little higher on a longer throw could help.
This pedal was set up this way by the previous owner, I just routed my cable through the existing hole.
This isn’t the best shot of the engine bay side, but you can see the little sheet of aluminum bolted on with the cable mounted through the center, routed up to the bracket.
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Yeah, that's really close to the hinge which will give you a short pull at the carb.
I'll grab a picture of mine later and post, I've used the same setup for quadrajet , sniper and an LS with just minor tweaks
I'll grab a picture of mine later and post, I've used the same setup for quadrajet , sniper and an LS with just minor tweaks
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I marked up your photo. I am able to thread the universal cable into a pre-existing threaded boss shown in green, I believe yours is where the red is?
Double the distance from the hinge will give you double the travel
Double the distance from the hinge will give you double the travel
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Or maybe you can use this hole if You can extend the pedal rod
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- #1,900
Thanks! I honestly can't remember what that other hole is from or what it was for. I was wondering if that might be an option if I were to extend the pedal.
It's interesting that you were able to use the existing threaded boss for the cable - Do you mean you just ground off/drilled out the boss to accept your cable, or did the firewall connection just screw right in? I honestly cant remember what the size/thread is of the cable mounting flange on the firewall but that would certainly make for a clean installation...