Progress Thread Hoopty v2.0 - Back in action!

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Hmmmm I wonder if the overly rich can actually put more pressure on the head gasket? That creates a hydraulic in the cylinder on the exhaust stroke. Do you smell any fuel in the oil? Seem running that rich you would be getting some cylinder wash?
 
Hmmmm I wonder if the overly rich can actually put more pressure on the head gasket? That creates a hydraulic in the cylinder on the exhaust stroke. Do you smell any fuel in the oil? Seem running that rich you would be getting some cylinder wash?
I honestly haven't had time to mess with it - I'll try and look at it this evening. But it was only a point rich at WOT, cruise was at or near stoich.

I'm betting small chambers, and flat top Pistons. A flat top 351 with a 69 cc head is a 10.7:1 engine.
But it's a stock long block. E7 heads are 64cc if I'm not mistaken. "small" chambers for SBF are in the neighborhood of 58cc. But this is all guesses until I can get in there and look. That's the other thing though, now that I'm on it. 10psi through an E7 head is a whole lot less air than 10PSI through any aftermarket head with larger runners. The car might have been making 350 hp at the crank... maaaaaybe? Something else has to be going on.
 
I honestly haven't had time to mess with it - I'll try and look at it this evening. But it was only a point rich at WOT, cruise was at or near stoich.


But it's a stock long block. E7 heads are 64cc if I'm not mistaken. "small" chambers for SBF are in the neighborhood of 58cc. But this is all guesses until I can get in there and look. That's the other thing though, now that I'm on it. 10psi through an E7 head is a whole lot less air than 10PSI through any aftermarket head with larger runners. The car might have been making 350 hp at the crank... maaaaaybe? Something else has to be going on.
I think that's wrong.
I have 100 cubic inches less than you. And all through the end of the last year, I ran that engine on the gate spring at 7psi. And my guess is 350 hp on my weanie assed engine at 7 psi. An Aussie Crossflow head is cast based on Late 70's technology. ( read,....not any better than what you got) my valves are 1.75/1.5" respectively. a turbo forces a weak head to flow air. Granted, a better head will flow more and make more power at a given boost level, but 10 psi on those heads with 351 ci under them has got to be at least 400 h.p.
The factory 351 c9ve "4bbl" head was 69 cc, w a 1.84" intake valve, and a 1.54 exhaust valve. according to factory specs was rated at 10.7:1 CR, and made 290 hp/385 tq.
So then,.. If those heads aren't 351 heads, and are 5.0 heads with an even smaller chamber by 5 cc's...........Man!....we're talking over 11:1 with a flat top piston.
Cylinder pressure is killing head gaskets here.
 
I think that's wrong.
I have 100 cubic inches less than you. And all through the end of the last year, I ran that engine on the gate spring at 7psi. And my guess is 350 hp on my weanie assed engine at 7 psi. An Aussie Crossflow head is cast based on Late 70's technology. ( read,....not any better than what you got) my valves are 1.75/1.5" respectively. a turbo forces a weak head to flow air. Granted, a better head will flow more and make more power at a given boost level, but 10 psi on those heads with 351 ci under them has got to be at least 400 h.p.
The factory 351 c9ve "4bbl" head was 69 cc, w a 1.84" intake valve, and a 1.54 exhaust valve. according to factory specs was rated at 10.7:1 CR, and made 290 hp/385 tq.
So then,.. If those heads aren't 351 heads, and are 5.0 heads with an even smaller chamber by 5 cc's...........Man!....we're talking over 11:1 with a flat top piston.
Cylinder pressure is killing head gaskets here.
No no. This is a bone stock 302. No 351 anymore.
 
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Man, I had to go back a few pages to dig this up!

Late last week, I began slowly tearing the motor down to get ready for a father's day wrench-a-thon (that's what I asked for, a day in the garage). Below are the driver's side bank of plugs, and it should be pretty obvious who the victim is here:

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So by Sunday, the motor was mostly torn down. Overall, it was a pretty pain-free process and I almost enjoyed it. Here is the busted gasket:

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So this is on a pretty conservative tune. High ten/low eleven AFR's, not a lot of timing, and 10psi. So, we're going to back the boost down to 6psi or so and hope that is below the threshold of damage.

I ALMOST got it running last night, except O'Reilly fudged my order, so the intake gaskets didn't come in. So that was a major let down.
Also, I did this, and didn't notice until I had tightened all the rockers down and put the valve cover back on.


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So that was a fun exercise.

Anywho, we should be back up and running in short order.
 
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Did you check the heads and deck for straightness? This guy got so fed up with it that he sold the car. I don't believe it will be as easy as replacing gaskets and turning the boost down.

Good luck though, I hope you figure it out.

Joe
 
Did you check the heads and deck for straightness? This guy got so fed up with it that he sold the car. I don't believe it will be as easy as replacing gaskets and turning the boost down.

Good luck though, I hope you figure it out.

Joe
The only straight edge i had was a metal ruler, but nothing stood out as odd. I spent a few minutes moving it around and shining a light to see if there were any gaps. But at this current juncture, i don’t have any money to throw at it, and i refuse to have it sit, so it’s going to go back together.
Maybe there was something in the timing he missed, maybe he was working out the tune, who knows.
 
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