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Bad Valve Guides?

601 is discouraging. Factory 305 head. Valve offered 1.72 or 1.84. 53cc chambers.

Since the intake have the PC seals, we know some machine work has been done. The heads have been milled at least once, the combustion chamber will be smaller.
Now the question is did the intake valves get increased to 1.94, or bigger.
As for new rockers at a 1.6 ratio, w/o being able to check piston clearance it would be dangerous.
I would save that cash for some good aftermarket heads.

Looking at 1st post video, the casting number appears to be 801 to me. Possible mismatched heads. Post a still of casting number of second head
 
Wes Harden said:
601 is discouraging. Factory 305 head. Valve offered 1.72 or 1.84. 53cc chambers.

Since the intake have the PC seals, we know some machine work has been done. The heads have been milled at least once, the combustion chamber will be smaller.
Now the question is did the intake valves get increased to 1.94, or bigger.
As for new rockers at a 1.6 ratio, w/o being able to check piston clearance it would be dangerous.
I would save that cash for some good aftermarket heads.

Looking at 1st post video, the casting number appears to be 801 to me. Possible mismatched heads. Post a still of casting number of second head
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Well here is the dilemma . For $800 I can put a 5.3 LS in it. If I don’t then I would put new heads on this.
 
yes miss matched heads. The 601 is preferable to the 801. They are very similar, both have same cc's and could have the same valves. Neither are worth any extra dollar investment.
 
Wes Harden said:
yes miss matched heads. The 601 is preferable to the 801. They are very similar, both have same cc's and could have the same valves. Neither are worth any extra dollar investment.
Click to expand...
What heads should I buy or should I just pull it and put a 5.3LS? I can use it in my other blazer
 
short answer idk, and depends. You need as much info about your short block as possible, weight of truck, gears, trans, and desired purpose to select a set of heads to compliment and perform. @folkenheath would be an excellent source for information and maybe even the heads.
 
Wes Harden said:
short answer idk, and depends. You need as much info about your short block as possible, weight of truck, gears, trans, and desired purpose to select a set of heads to compliment and perform. @folkenheath would be an excellent source for information and maybe even the heads.
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Sounds great, I agree!

I am a big fan of Brodix IK180s with the 65cc chambers
 
Blue85 said:
With a free 5.3 and some aftermarket motor mounts already sitting in your shop, this is still very optimistic.
Click to expand...

it’s not free I have to buy it for 800 bucks and then I have to buy new motor mounts fuel system, flywheel, etc. to make it work
 
It depends on what you want, if you are going to do the LS swap I would recommend finding a 6.0 if you can, same work and more potential torque and HP, but if you are good with the 5.3 then go for it.

You are correct on the swap, costs can add up quick, they can add up quick on the SBC rebuild too. I do agree, the Brodix IK180, IK stands for Iron Killer, is a very good option, they are selling a relatively inexpensive quality aluminum head for a good price.

I would need to know a lot about your build and plans to help you select the heads, so we get the correct static/dynamic compression to work with your cam and pistons, and the torque curve and idle characteristics to match your vehicle and transmission, gearing, etc.
 
@folkenheath

So I removed the passenger side cylinder head.

Turns out this crate 350 has been punched out .060 over. Damn :(

Walls, flat tappet lifters and cam(still in the block) looked great, block was clean, The valves are stock 305 heads.

No wonder this thing was a dog.

Fel-Pro 7733PT-2: Economy Head Gasket Chevy 262-350 except 305 - JEGS

Economy Head Gasket
www.jegs.com www.jegs.com

Compressed Thickness (in.):
0.039 in.

Sealed Power H580CP: Hypereutectic Pistons 1991-1995 Small Block Chevy 350 ci / 5.7L [4.000 in. Bore Standard] - JEGS

Get the Best Performance with Sealed Power Hypereutectic Pistons 1991-1995 Small Block Chevy 350 ci / 5.7L [4.000 in. Bore Standard] H580CP parts at JEGS. Shop Now at the Guaranteed Lowest Price!
www.jegs.com www.jegs.com


Not sure what to do at this point. I definitely don’t want to invest thousands into a .60 hour vet block (which I don’t even know if the cylinders are totally round)

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Do you know how many years/miles since the rebuild? It looks very clean inside and aren't those aftermarket pistons? If it's been running well for some time, doesn't that mean the .060 treatment is now proven to be good? We don't know if the block was sonically checked or whatever, but if it was going to crack and puke coolant or overheat, wouldn't it already be doing that?

So what are you considering?
  1. Buy some decent aftermarket heads for like $1400 and keep the truck SBC indefinitely
  2. Find some used 350 heads for like $300 and just be happy that it runs like it's supposed to
  3. Put the 305 heads back on and live in sorrow until the LS swap is ready
  4. Give up, park it and start spending on LS swap parts
 
My thoughts are- this block is end of life. 60 over is the end. I don’t want to buy nice shit for it haha. I can get a complete 5.3 motor, harness, computer, and accessories with like 140k miles for 800. One side had 601s and the other has 801s. If they were the same I’d have these heads ported.

Worst comes to worst, I don’t think I’ll need to rebuild this motor probably ever again. Just don’t drive it enough nor do I drive it hard. I can always transfer my shit over to a new block.
 
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Well, yeah, it can't be bored again, but a SBC should be good for a couple hundred thousand miles between rebuilds, no? So the good news is you only need 1 head? For sure whatever the new engine is, there will be problems associated with the swap. If that's what you really want long term, then by all means go for it instead of spending money on this one, but don't think of it as an easy way out. Another set of heads and you could have this thing running in an afternoon, vs months of collecting parts and dealing with little issues.
 
Blue85 said:
Well, yeah, it can't be bored again, but a SBC should be good for a couple hundred thousand miles between rebuilds, no? So the good news is you only need 1 head? For sure whatever the new engine is, there will be problems associated with the swap. If that's what you really want long term, then by all means go for it instead of spending money on this one, but don't think of it as an easy way out. Another set of heads and you could have this thing running in an afternoon, vs months of collecting parts and dealing with little issues.
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Good point, I should probably get the heads and cam, call it a day.
 
I think the problem is now- the dish on these pistons are sooo big that I’ll be lucky to get 8.5:1
 
don't spend money on those heads. I see the lifters are out did you keep them in the correct order. Can you put them back in the exact hole it they were removed from ?

Good set of heads with calculated compression larger valves. Not sure I would change the cam unless the lifters are bad. If changing the cam go retro fit roller.
 
need to measure the top off the piston to deck of block (deck clearance) at tdc, so we can figure compression ratio
 
Guessing at deck height of .015, with .039 felpro head gasket, 56 cc will get you close to 9-1 compression. the heads you pulled were @ 58 cc unmilled.
 
Wes Harden said:
Guessing at deck height of .015, with .039 felpro head gasket, 56 cc will get you close to 9-1 compression. the heads you pulled were @ 58 cc unmilled.
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I’m calculating that these pistons have -25cc dish
 
I used 1.54 in for the calculations, I couldn't find the spec in cc. - should be for a domed piston and + for dish since a dish adds more cc's. Using 25cc the calculation only changes .02 8.96 to 8.98
 
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