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Could be worse!
I don't know how much worse it could be, but it could be!
LOL the only thing I haven't touched at this point is the Crank, Rods, Pistons and associated bearings. Thankfully those were assembled by Chevrolet not Bubba.
LOL the only thing I haven't touched at this point is the Crank, Rods, Pistons and associated bearings. Thankfully those were assembled by Chevrolet not Bubba.
With everything you've found, it might be worth it to pull them, inspect everything and reassemble.
I've pulled the radiator, both cylinder heads, all of the accessories. Heads are going to a shop to get checked.
I'm going to sell the BeCool radiator/fans/overflow tank that were on it, I ordered a DeWitts HP series kit for my 1970. I picked up a Mighty Demon 850 CFM to replace the 950 ProForm that was on it.
What I've learned so far:
- Water pump is correct, it's a standard rotation Edelbrock Victor, P/N 8850, which is correct for my serpentine set up, it looks fine, spins freely
- Unrelated, all 4 tie rod ends were missing cotter pins!!
- The cylinder head bolt torque was all over the place, some were just past snugged down, others took a 2' piece of pipe on a 18" breaker bar to get loose. They're ARP head bolts
- The pistons (and heads) were caked with soot from an overly large carburetor not jetted properly, heads LOOK to be in great shape, wiped down the pistons with carb cleaner, worked pretty well. (Subsequently wiped them down with oil)
- The passenger side head / pistons were noticeably cleaner than the driver's side for whatever reason (Coolant getting into the cylinder?)
- It has high end steel full roller rockers on it, a Lunati hydraulic roller cam most likely as that's what's on the roller lifter crossbar.
I am going to pull the harmonic balancer and see what camshaft is in the damn thing while I'm at it. In for an ounce, in for a pound.
Guessing it will take me a couple of weeks to come back out the other side of the tear down....
You will like the Dewitts with dual fans. I have it and my 496 can idle all day in the heat.
FYI I still have the water pump to manifold bypass hooked up with no issues at all.
( Also wanted to reply and make sure I saw how this who-done-it turns out)
Last edited by scottjamison; Jun 12, 2019 at 03:52 PM.
Couple of thoughts. I am running a 496 BBC, older March Serpentine, 195 hi flow stat, DeWitt radiator and dual Spal fans (controlled by FAST XFI 195 on/185 off) in FL with no issues.
1) March likes to include a "Performance" crank pulley in their serpentine kits. This is a smaller diameter pulley to slow down the accessories and increase HP. I called March and got a larger crank pulley (7" vice 5-3/4") which helped speed up the water pump (also helped with the alternator at idle). Just need to get a longer belt.
2) Spoiler. I have a '75 with the stock spoiler. I added the '79(?) L-82 spoiler extension and that really helps keep the car cool at speed.
Bottom line, in traffic fans cycle and keep car cool. Above 40 mph, fans are not needed at all.
Couple of thoughts. I am running a 496 BBC, older March Serpentine, 195 hi flow stat, DeWitt radiator and dual Spal fans (controlled by FAST XFI 195 on/185 off) in FL with no issues.
1) March likes to include a "Performance" crank pulley in their serpentine kits. This is a smaller diameter pulley to slow down the accessories and increase HP. I called March and got a larger crank pulley (7" vice 5-3/4") which helped speed up the water pump (also helped with the alternator at idle). Just need to get a longer belt.
2) Spoiler. I have a '75 with the stock spoiler. I added the '79(?) L-82 spoiler extension and that really helps keep the car cool at speed.
Bottom line, in traffic fans cycle and keep car cool. Above 40 mph, fans are not needed at all.
Where did you get the 79 spoiler? That might be good for mine.
I don't have the seals in yet (they just arrived) so my fans still cycle on the highway, so I want to get those on and look at removing the license plate and the better spoiler.
Where did you get the 79 spoiler? That might be good for mine.
I don't have the seals in yet (they just arrived) so my fans still cycle on the highway, so I want to get those on and look at removing the license plate and the better spoiler.
I got it from Wilcox Corvette. Not sure if it will work with the chrome bumper cars but works great on rubber bumper (73-79 w/o the pace car spoiler). It basically rivets onto the stock spoiler.
BigBill- in the post where you show your head, head gasket and block- think it is post #45- unless I am putting the gasket on from the photo incorrectly, it looks like your front and rear coolant passages are blocked off by the gasket. If that is the case, your front and rear cylinders are getting coolant flow only from the passages at the outer and inner side of the block and would run a lot hotter than they are supposed to. Or am I looking at the photo wrong? When I did the 454 in my convert, the head gaskets that came with the rebuild kit were wrong and the holes on the gaskets did not line up with the holes on the block/head. Fortunately I noticed before I put everything together and got the correct ones.
BigBill- in the post where you show your head, head gasket and block- think it is post #45- unless I am putting the gasket on from the photo incorrectly, it looks like your front and rear coolant passages are blocked off by the gasket. If that is the case, your front and rear cylinders are getting coolant flow only from the passages at the outer and inner side of the block and would run a lot hotter than they are supposed to. Or am I looking at the photo wrong? When I did the 454 in my convert, the head gaskets that came with the rebuild kit were wrong and the holes on the gaskets did not line up with the holes on the block/head. Fortunately I noticed before I put everything together and got the correct ones.
Couple of thoughts. I am running a 496 BBC, older March Serpentine, 195 hi flow stat, DeWitt radiator and dual Spal fans (controlled by FAST XFI 195 on/185 off) in FL with no issues.
1) March likes to include a "Performance" crank pulley in their serpentine kits. This is a smaller diameter pulley to slow down the accessories and increase HP. I called March and got a larger crank pulley (7" vice 5-3/4") which helped speed up the water pump (also helped with the alternator at idle). Just need to get a longer belt.
2) Spoiler. I have a '75 with the stock spoiler. I added the '79(?) L-82 spoiler extension and that really helps keep the car cool at speed.
Bottom line, in traffic fans cycle and keep car cool. Above 40 mph, fans are not needed at all.
Interesting, I just measured the crank pulley, it's a 7" pulley.
Not seeing anything that would fix the overheating (maybe I missed it).
I believe #5/#7 were leaking exhaust into the cooling system based on the compression check. Then I found out why that might be the case, the heads were not installed properly.
I've been continuing to work on getting it back together.
Key findings:
1.) Bubba just tossed the distributor into the motor without adjusting the advance springs. It had the "as shipped" heavy springs in it, black bushing, timing was too retarded.
2.) Bubba used incorrectly sized t-clamps, the upper radiator hose at the water neck t-clamp is not tight enough, allowing air to get sucked into the system
3.) Bubba tossed the wrong size vacuum hose from the carb to the TH400, it was just on/over the vacuum solenoid nipple - vacuum leak
Other observations:
The DeWitts HP series radiator is impressive. Be aware that the petcock ships in an "open" position, I suggested to DeWitts that they either tag it or ship it closed
DeWitts suggests you ground your aluminum radiator and includes a ground wire for the radiator
Hedman 2' primary headers and a borgeson box bolt right in, the passenger side header needed to have some small dents for clearance. They're a great size for stock port diameter (Performer RPM, etc), and bolt right up.
If you use a mini-starter, you'll have to reclock it for headers vs manifolds (no biggie)
Getting close to getting this thing back together......
Just for the heck of it, stop at a radiator shop and have them use an exhaust gas analyzer for the radiator. You want to make sure there is zero exhaust gas in the coolant which will cause stream pockets.
I bought a Dewitts heavy duty radiator with twin fans for my 454, that works well but the other mod was a front spoiler extension, It's the one for the 79 Vette easy to fit and made from a rubber compound it's ok on kerbs and very easy to fit
i think we are all losing out on some cooling air when car is in motion. look at the ends of all airliner wings. the swept-back wing causes spanwise flow. air hits the wing and turns and runs along instead of over the wing. so they put winglets on to reduce that direction of flow. our under nose splitter (splitter-spoiler) is shaped the same way. i think a forward angled tip would decrease the air travelling sideways and make it go up into the radiator where we want it. this is a cardboard quicky i threw on. might want to look at the holes in the valence and set the diverters at the best spot.
Last edited by derekderek; Jul 5, 2019 at 08:23 AM.
I wanted to follow this up and close it out for anyone that can get value out of it for their own concerns.
The car is back together, and it no longer overheats. I did install the "tire material" chin spoiler extension mentioned above. Figured it was cheap insurance. It looks good as a bonus.
Primary culprits to my problem, courtesy of bubba:
- Improperly installed cylinder heads (Household silicon, missing/upside down beveled washers, etc etc)
- Improperly configured distributor (Just stuck in there with the factory double black / heavy springs, factory bushing) - heavily retarded
- Improperly sized T-Clamp at the upper radiator hose
- Mismatched carb/cam/exhaust (big cam, giant carb, stock manifolds)
I found a lot of other bubba-a$$ stuff while I was in there that I fixed. I may or may not have snuck a RideTech front suspension in.
It runs great. Figured I would share a few current pictures.
Next step - off to the exhaust shop next week to get 3" pipes put on it...
Thanks to all for all the information, and suggestions. Hopefully this thread will help someone else out in the future.
If you would, please post a photo of the new 3” exhaust and a short video of how it sounds.
I’m putting 3” with an X pipe on my big block and I’m looking for examples.
Glad to here you got everything sorted out.
Thanks
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