L T headers, and heat soaked starter.

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rebelyell

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Ok, so this is my issue. It is on my 1979 Corvette, not my truck, but my Vette, has its OE 4 bolt main, 350 in it. The LT headers are very close to the starter. It has a metal heat shield, but it is almost touching the header. The starter definitely has heat soak issues. So, here is my question. Anybody running a starter from a 2000ish, 4.3L on there GMT 400. The 2000 plus starter, is a smaller starter. If you are using this starter, please reply, and let me know how you like it. Yes, I know, there are a ton of mini starter options out there, and at a lot of different prices. That's not what I'm asking. I specifically what to know about the 2000 + 4.3 smaller starter. Thanks in advance.
2-page TSB from REMY starters --- about upgrading from old heavy 10MT straight drive starter to modern light PG260 starter ( as found on later GM trucks also 5.0L & 5.7L V8 iron head97-2002 trucks).
Do Pay CLOSE ATTENTION to Starter Bolts! They're NOT the same as your old bolts and IT MATTERS HEAPS!

If your C3 motor has smaller 153T flywheel/flexplate, you'll need a "Straight" starter.
If it has 168T, ya need a "staggered" starter.
Your '79 should have HEI dist; should Not need an "R" terminal on solenoid.


*I've had only good experience w/starters & alternators from DB Electric of Kingsport TN


*** '79 C3 most likely has OE 168T flywheel/flexplate --- therefore a staggered starter also.

**** the modern OE PMGR starters have such a smaller profile than old OE 10MT starters, chances are it'll stand off from exhaust far enough that you should Not bother w/ blanket or shield.
 
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Hipster

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Starters. sometimes it comes down to the clocking of the solenoid as to whether you can get them inside the headers, adjustable clocking ones are out there, but not economical by any means.Timing, sometimes you just need to give the engine what it needs, Plenty of variables where tech support might not have specific info you need. Different head flow, cam etc. IVC on the cam, and how it relates to "known" cylinder pressures etc. Unless your cam is in the 235-240+ range @ .050 less initial might be just fine and start "hot" better. 16 BTDC is a fair amount for less. How the distributor is set up matters, controlled by ecm, mechanical etc.
 

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2-page TSB from REMY starters --- about upgrading from old heavy 10MT straight drive starter to modern light PG260 starter ( as found on later GM trucks also 5.0L & 5.7L V8 iron head97-2002 trucks).
Do Pay CLOSE ATTENTION to Starter Bolts! They're NOT the same as your old bolts and IT MATTERS HEAPS!

If your C3 motor has smaller 153T flywheel/flexplate, you'll need a "Straight" starter.
If it has 168T, ya need a "staggered" starter.
Your '79 should have HEI dist; should Not need an "R" terminal on solenoid.


*I've had only good experience w/starters & alternators from DB Electric of Kingsport TN


*** '79 C3 most likely has OE 168T flywheel/flexplate --- therefore a staggered starter also.
Yes, it's a staggered starter. Just installed the heat blanket. That didn't help. Guess I'm replacing the starter. As for the HEI, that's long gone. It has the Holley sniper set up, with the Holley hyperspark distributor. All controlled by the sniper system.
 

rebelyell

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Yes, it's a staggered starter. Just installed the heat blanket. That didn't help. Guess I'm replacing the starter. As for the HEI, that's long gone. It has the Holley sniper set up, with the Holley hyperspark distributor. All controlled by the sniper system.
"R" terminal primarily to supply full current during cranking; and then reduces current during points run.
I dunno, but doubt hyperspark dist requires an "R" terminal --- but You should verify what's required.

Reference that REMY TSB for GM PNs for correct bolts; small money at local dealership Or DB sells a pair for $20. In the case of staggered; both bolts are same length. Their knurl & taper Very important.

check those battery cables behind C3 driver seat. Up inside insulation they can be corroded; preventing starter from getting full current when cranking --- have had two C3.
Being a welder, maybe you can make up some HD cables?
 
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L31MaxExpress

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"R" terminal primarily to supply full current during cranking; and then reduces current during points run.
I dunno, but doubt hyperspark dist requires an "R" terminal --- but You should verify what's required.

Reference that REMY TSB for GM PNs for correct bolts; small money at local dealership Or DB sells a pair for $20. In the case of staggered; both bolts are same length. It's knurl & taper Very important.
Dorman has the correct length, shouldered bolts as well. I bought a box of 10 of them from Oreilly.

My Proflow 4 calls for 12*, GM PMGR spins the 10.25:1 350 right over even with a 550cca battery. I did upgrade to new 2 awg battery cables I built. A set of cable crimpers and the materials to make new cables were very affordible. I converted mine to a 24F top post, because I cannot stand the side posts. May or may not have room under the Vettes rear compartment cover for a top post. I took a wizz wheel to the block where I bolted the negative cable to ensure it had a good connection, it was a little rusty and had some paint on it from GM. I cleaned the used starter and starter pad in the same manner. You want nice shiny metal where the cables mount and the starter bolts contact the starter.

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Hipster

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check those battery cables behind C3 driver seat. Up inside insulation they can be corroded; preventing starter from getting full current when cranking --- have had two C3.
Being a welder, maybe you can make up some HD cables?
Haven't messed with many but on my FIL's vette this was the issue.
 
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1979 Corvette 350

The LT headers are very close to the starter. It has a metal heat shield, but it is almost touching the header. The starter definitely has heat soak issues.
DEFINE "HEAT SOAK ISSUES".

Does it crank slowly, or not crank at all? Does it crank, then stop, then crank again?

IF (big IF) it DOES NOT CRANK, you've probably got issues with the wire harness from ignition switch to neutral safety or clutch safety switch, through the bulkhead connector, and then down the purple wire to the "S" terminal of the starter. This may not be a starter problem at all, it could easily be a wiring problem. Common as dirt.

Anybody running a starter from a 2000ish, 4.3L on there GMT 400. The 2000 plus starter, is a smaller starter. If you are using this starter, please reply, and let me know how you like it.
WHICH starter is this? Photo? Link? Part number? GM has multiple versions of permanent-magnet, gear reduction (PMGR) starters.

I definitely will wrap it with a heat blanket. It has a metal heat shield on it now, but that's not really do the job.
DO NOT install a "blanket" over the starter. The blanket can prevent exhaust heat from getting to the starter. It will also prevent the heat inherent in ~200 amperes of starter-motor current from getting OUT of the starter motor.

Metal heat shields with an air-gap to the starter 'n' solenoid are MUCH better. Exhaust heat doesn't get in, starter heat does get out--carried away by the air flow through the air-gap between starter/solenoid and heat shield.

2-page TSB from REMY starters --- about upgrading from old heavy 10MT straight drive starter to modern light PG260 starter ( as found on later GM trucks also 5.0L & 5.7L V8 iron head97-2002 trucks).
Do Pay CLOSE ATTENTION to Starter Bolts! They're NOT the same as your old bolts and IT MATTERS HEAPS!
ABSOFUKKINLUTELY!

Just installed the heat blanket. That didn't help.
Blankets are a mistake. Put the metal heat shield back on.

Guess I'm replacing the starter.
A PG260 PMGR starter as detailed in the link already provided is what's on my 88 K1500 5.7L, and also on my '97 K2500 7.4L. Same starter used on the 8.1 and some V6s.

But the REAL issue is likely to be poor conductivity on that purple wire leading to the "S" terminal. I had to replace about three feet of that wire on my '97 K2500 because it was corroded black at the starter...and the last five or six inches by the solenoid had been replaced by the previous owner before I bought the truck. The wire was corroded back at least another foot--behind the bellhousing where I couldn't access it. I spliced into the harness above the engine, and dropped new, clean wire down to the starter solenoid. End of problems.

Previous "repair"
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The blue connector above was spliced into the black end below. The other end--about eight inches back--was better but still more corroded than I was willing to accept.
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I couldn't find purple wire of 12-gauge, so I used red. Crimped, then soldered, and eventually heat-shrink protected into the existing, non-corroded purple wire.
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About 3 feet of fresh wire dropped down alongside the original wire, and routed to the "S" terminal of the starter solenoid.
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rebelyell

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Either of these two PMGR will fit a '79 C3; both are staggered (if ya don't need "R" terminal, simply ignore it).
either fit sbc or BBC
Marine starters are sealed better and are more robust
Do get the correct bolts!
New starters cain't fix bad cables.

*none of the OE starters for serial production vehicle are "clockable"


 
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DEFINE "HEAT SOAK ISSUES".
Heat soak issues. So the car spins a little slow, but starts fine, when the engine is cold. Example. Monday, I went to a store, that sales lunch plates. Grate food, and inexpensive too. Car was cold, when I left in it. Let it warm up to 160+ and go into open loop, as Holley says to do, with the sniper EFI. Left home, and drove about 7 or 8 miles. Got there, and went inside to get a lunch plate. Took maybe 5 mins max. When I got there, a guy in a truck, was admiring my Vette. Came back to start it, and the starter spun very slowly. Pulled the volts down to 9 volts. Back to around 12 volts, when I let off of the key. So, I put my window down, and asked the guy, if he had a set of jumper cables. He said, no, but I have a jump box. OK, perfect. I hook it up to the battery. It showed 12.8 volts. Turned the key, and again, dropped to 9 volts. Released the key, and back to 12.5 volts, and now his jump box is at 85 percent. Was at 100 before I hooked it up. I let it sit for about 1 min, and the jump box is back at 100 percent. Try again. 12.8, until I turn the key, and 9 volts with the key in the start position. After 2 attempts, I didn't want to hold this guy up, so, I said, don't worry about it. I will get it started . I open the hood, and double check the wires on the alt. All good there, no to mention, I was at 13.0 to 13.5 before I stopped at that store. So after sitting and fooling with the car, for about 5 mins are so, it fires up. Starter was spinning closer to normal speed. I put the car in the back yard, and go eat my lunch. Come out, once I'm done, and it starts decent. Still a little slow, on spinning the engine, but not bad. So, now I'm experimenting with the issue. Once I start it, again, I let it run to 195ish. Turn it off. Then try to start it. Starter spins slow, but the car does start. I do it again, and back to the very slow spin, ( about 1 revolution of the flywheel) and it stops, then a few seconds later, a 1/2 a revolution of the fly wheel, then it stops. All the while back to 9 volts. So again, I pop the hood, and let it sit for about 15 mins. The car starts. Not a fast spinning start, but fast enough to fire up the engine, and 11.5 to 12 volts. I got in it this morning, and fired it up. Volts fell to 12.5. pulled it out, put it on ramps, and went got some heat blanket for starters. I could not get it around the starter, BC of the metal heat shield, that is on the starter, and against the header. So , I decided to wrap the header. After doing that, I do the same test. Get it up to 195ish. Same situation. Would not spin the engine fast enough to start. I leave for about 2 hours. While I'm gone, my wife gets in the car, and starts it up, to move it so she can cut the grass. It starts fine. I replaced the battery in the car last month. Battery cables look fine. No corrosion. Keep in mind that all C3 Corvettes battery's, are in the floor, behind the driver's seat. As for the starter, this is the one I am talking about. It fits a 1999, to 2004, I think 4.3L Silverado, a 4.3L S10, a 4.3L Isuzu, and IDK what all else. These starters, are smaller than a 350 starter. I think I will go to the junk yard tomorrow, and get 1. That way, if it doesn't pan out well, I won't have lost much money.
 

rebelyell

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Heat soak issues. So the car spins a little slow, but starts fine, when the engine is cold. Example. Monday, I went to a store, that sales lunch plates. Grate food, and inexpensive too. Car was cold, when I left in it. Let it warm up to 160+ and go into open loop, as Holley says to do, with the sniper EFI. Left home, and drove about 7 or 8 miles. Got there, and went inside to get a lunch plate. Took maybe 5 mins max. When I got there, a guy in a truck, was admiring my Vette. Came back to start it, and the starter spun very slowly. Pulled the volts down to 9 volts. Back to around 12 volts, when I let off of the key. So, I put my window down, and asked the guy, if he had a set of jumper cables. He said, no, but I have a jump box. OK, perfect. I hook it up to the battery. It showed 12.8 volts. Turned the key, and again, dropped to 9 volts. Released the key, and back to 12.5 volts, and now his jump box is at 85 percent. Was at 100 before I hooked it up. I let it sit for about 1 min, and the jump box is back at 100 percent. Try again. 12.8, until I turn the key, and 9 volts with the key in the start position. After 2 attempts, I didn't want to hold this guy up, so, I said, don't worry about it. I will get it started . I open the hood, and double check the wires on the alt. All good there, no to mention, I was at 13.0 to 13.5 before I stopped at that store. So after sitting and fooling with the car, for about 5 mins are so, it fires up. Starter was spinning closer to normal speed. I put the car in the back yard, and go eat my lunch. Come out, once I'm done, and it starts decent. Still a little slow, on spinning the engine, but not bad. So, now I'm experimenting with the issue. Once I start it, again, I let it run to 195ish. Turn it off. Then try to start it. Starter spins slow, but the car does start. I do it again, and back to the very slow spin, ( about 1 revolution of the flywheel) and it stops, then a few seconds later, a 1/2 a revolution of the fly wheel, then it stops. All the while back to 9 volts. So again, I pop the hood, and let it sit for about 15 mins. The car starts. Not a fast spinning start, but fast enough to fire up the engine, and 11.5 to 12 volts. I got in it this morning, and fired it up. Volts fell to 12.5. pulled it out, put it on ramps, and went got some heat blanket for starters. I could not get it around the starter, BC of the metal heat shield, that is on the starter, and against the header. So , I decided to wrap the header. After doing that, I do the same test. Get it up to 195ish. Same situation. Would not spin the engine fast enough to start. I leave for about 2 hours. While I'm gone, my wife gets in the car, and starts it up, to move it so she can cut the grass. It starts fine. I replaced the battery in the car last month. Battery cables look fine. No corrosion. Keep in mind that all C3 Corvettes battery's, are in the floor, behind the driver's seat. As for the starter, this is the one I am talking about. It fits a 1999, to 2004, I think 4.3L Silverado, a 4.3L S10, a 4.3L Isuzu, and IDK what all else. These starters, are smaller than a 350 starter. I think I will go to the junk yard tomorrow, and get 1. That way, if it doesn't pan out well, I won't have lost much money.

Oh, it's a near certainty it'll crank over easier w/ the PMGR starter, Even If The Cables Are Bad.
Because PMGR starter does Not have field coils; it requires considerably less current spin sbc up.
So don't let that fool you into thinking the cables Must be AOK. We cannot see thru the cable insulation and gage whether the conductor(s) are corroded; we can only see the conductor(s) at their terminals.
No I don't KNOW what good cables' resistance range is. Someone else might.
But, it's what's Inside that insulation that hides from us. Trust; but verify.

IIRC, SMP makes a good replacement cable; and SMP did make them for C3 (albeit for side-posts).
 
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