Restoring Rusty

[enaberif]

Spark plug gap on a HEI Chevy should be .045 as .030 was for a points system. Yes using the wrong gap will make a vehicle run like absolute crap. When I put plugs in my truck they were gapped for .030 and I could not get it to run properly no matter what.

Also doing vac gauge measurements I am pretty sure it should be on manifold vacuum not ported vacuum as should your distributors vacuum advance to get optimal performance.

[Gregski]

Originally Posted by enaberif

Spark plug gap on a HEI Chevy should be .045 as .030 was for a points system. Yes using the wrong gap will make a vehicle run like absolute crap. When I put plugs in my truck they were gapped for .030 and I could not get it to run properly no matter what.

interesting, we are going to try all on .040 as per the GM Performance Spec sheet, but may bump it up to .045 as you recommend if needed

Originally Posted by enaberif

Also doing vac gauge measurements I am pretty sure it should be on manifold vacuum not ported vacuum as should your distributors vacuum advance to get optimal performance.

it is

[hatzie]

Originally Posted by enaberif

Spark plug gap on a HEI Chevy should be .045 as .030 was for a points system. Yes using the wrong gap will make a vehicle run like absolute crap. When I put plugs in my truck they were gapped for .030 and I could not get it to run properly no matter what.

Also doing vac gauge measurements I am pretty sure it should be on manifold vacuum not ported vacuum as should your distributors vacuum advance to get optimal performance.

I used to run .060 gap with a Jacobs Mileage Master multi spark setup on my 1985 5.0L C10. She ran nice and smooth. That or an MSD6AL is about the only aftermarket coil system I would use because it doesn't bork the stock ignition module. The mileage gains were not enough to make the price worthwhile.

Run the gaps as wide as you can get away with it lights the fuel better. .045 is a good number for stock HEI with a new Delco coil and Ignition module.

[blazer2007]

I was just curious why the engine would overheat with the heater lines plugged,my big block is capped and it runs fine.Is your style engine have a different water gallery set up that would cause that?

[Gregski]

Originally Posted by blazer2007

I was just curious why the engine would overheat with the heater lines plugged,my big block is capped and it runs fine.Is your style engine have a different water gallery set up that would cause that?

my best guess is that something is wrong, we have not truly found the source of the problem yet, I agree that it should run without the heater core, and without the bypass hose from the intake to the water pump

let me get passed this vacuum issue and then I may try a different water pump, and maybe a more than single core radiator after that, maybe go aluminium

[Oberon67]

I been looking at your photos... y'all gonna have to change that truck's name.

[Gregski]

Originally Posted by Oberon67

I been looking at your photos... y'all gonna have to change that truck's name.

ha ha, not just yet, we still have to tackle the kick panels inside the cab and pull the dash completely out to see what lurks behind it (Winter Project?)

[Gregski]

well, gapped the plugs this morning to .040 (for starters) and warmed him up for 10 minutes, and then tested with the vacuum gauge again, and no change needle is still jumpy, dang

valve adjustment coming up next after my dentist appointment

[68post]

Dentist appt. !! Don't take it out on poor Rusty, he has to be worried now.

[Gregski]

Originally Posted by 68post

Dentist appt. !! Don't take it out on poor Rusty, he has to be worried now.

thought about it, but they have some heavy lube on them so that probably will add thickness to it, so I just used that wire wheel one, I may pick up a proper feeler gauge set today, I like decent measuring implements when I can afford them

[Gregski]

Originally Posted by 68post

Dentist appt. !! Don't take it out on poor Rusty, he has to be worried now.

Ha, ha, Rusty is about to meet the 3 lbs sledge if he don't shape up real quick!!!

[rich weyand]

What vacuum can are you running? That can make the engine throb like that, although that is usually on the low end of vacuum, not the high end where you are.

[Gregski]

Originally Posted by rich weyand

What vacuum can are you running? That can make the engine throb like that, although that is usually on the low end of vacuum, not the high end where you are.

hi Rich, what can are you talking about? if the one on the dizzy than I am not using that during the test, its like setting initial timing, no vacuum advance

[enaberif]

Originally Posted by Gregski

hi Rich, what can are you talking about? if the one on the dizzy than I am not using that during the test, its like setting initial timing, no vacuum advance

1) Initial timing = vacuum advanced unplugged

2) Mechanical Advance = How much your distributor pulls with weights and springs

3) Total Timing = Initial + Mechanical @ 2500-3000 rpm

4) Carb tuning is 1-3 setup PLUS vacuum advance

Vacuum advance is there to help with idle and cruise and can help with MPG

[rich weyand]

No, it's not like initial timing. You need to tune the carb with the vacuum advance hooked up. There's your problem. You are running a way-too-late spark.

[Gregski]

Originally Posted by rich weyand

No, it's not like initial timing. You need to tune the carb with the vacuum advance hooked up. There's your problem. You are running a way-too-late spark.

Koogle Mooglie, lemme re test than, and get back atcha all

[Gregski]

decided to do a compression test before doing a valve adjustment, it's always good to have a baseline

man I was so bummed to find out that my trusty ol' compression gauge was not working, it read 0 for the first 4 cylinders

so rented one from AutoZone for $40 bucks (which they refund you if and when you return the tool) before Pontiac Mike told me to check the Shrader valve on my old hose, and sure as sheet the cheapo tiny valve is bad, so that tells me my gauge may be good after all

[Gregski]

man my cylinder pressure looks great, #1 and #2 were initially low but retested great

I always like to test twice once 1 through 8 and later on after re warming up the vehicle 8 through 1

[Gregski]

#1 - 140 psi

#2 - 140 psi

#3 - 150 psi

#4 - 151 psi

[Gregski]

#5 - 150 psi

#6 - 149 psi

#7 - 145 psi

#8 - 150 psi

[enaberif]

I'd say with those numbers you are fine.

[Gregski]

Originally Posted by enaberif

I'd say with those numbers you are fine.

I would agree, for a 40 year old bottom end, we'll take those numbers all day long won't we?

[68Timber]

Originally Posted by Gregski

I would agree, for a 40 year old bottom end, we'll take those numbers all day long won't we?

There's a joke in there somewhere.

[Woodyboat]

Originally Posted by 68Timber

There's a joke in there somewhere.

ROTFLOL!! My thoughts exactly!!

[flashed]

So Greg ,now that you have completely ruined that old truck ,How much you want for it for me to take it away from your misery ? Really kidding you ,I love what you have done with it .