84 Z28 Camaro when I bought it at a 305 in it that was pretty wore. But it came with an extra motor a 307 somebody bored out to a 350. The guy I got it from said it was just 30 over when I pulled the oil pan I had my brother there's a machinist bring out his measurement tools and we found out I had a 4 inch bore.

Issue Number 1 car is having a slight overheating problem. it's hanging around the 230 240 range. Thermostat is a 190 with stock water pump. Temp sender is in the driver side port on the intake. Can't seem to figure out the problem.

Problem number 2 I have the engine timed to around 12 degrees. I can see the timing mark jumping around 1 to 2 degrees each Direction with the timing light. And yes the vacuum advance is unhooked when I do this. Also when I first go to start it sometimes the starter will bog down a little bit like the timing is out of whack. Then the starter will catch and start turning the engine over just fine. It's also a little hard to start in the morning.

 

Are you using the stock clutch fan?
Is the clutch known good?
Shroud in place? Lower deflector(s) in place?

Why the Torker II single plane intake?

 

Yes I'm using the stock clutch fan. Both shrouds are in place. The Dual plane that came with it had a crack in it I had the torker 2 laying around in the shed it's just temporary till payday. Still got to figure out what intake would go good with what I have. Thinking of running an air gap

 

Yes I'm using the stock clutch fan has a new clutch. Both shrouds are in place. The Dual plane that came with it had a crack in it I had the torker 2 laying around in the shed it's just temporary till payday. Still got to figure out what intake would go good with what I have. Thinking of running an air gap

 

Also I don't seem to be building much pressure in the radiator. Also check there's no leaks into the oil and no oil in the coolant. Pull the water pump pull the backing plate off of it everything's nice and tight like it should be impeller blades look brand new. I do have a brand new push fan with a wiring harness that I never installed due to the fact they sent me the wrong fan as I was wanting a pull fan. Thinking about trying to install it as an assist to the clutch fan. Or should I go with a flex fan?

 

You can't bore a 307 .125". Whoever told you that, is feeding you canal water. Alot of em had trouble going much past .030" when they were new.

Get the block casting # and we can help figure out what you REALLY have. It would also be helpful to know what pistons are in it, by part #.

Reason is, if it's REALLY a 307, and let's be generous and allow that it might be .060" over:

316 CID
76 cc head chambers (nominal "spec" for 882)
.041" head gasket
.045" deck clearance (the stock .025", plus the added .020" in virtually ALL replacement pistons, especially cast ones)
Flat tops (you don't say so I have to guess here)
6 cc valve reliefs

Compression ratio = ~7.5

But, you have a cam that needs AT LEAST 10:1 in a 350, and would need even more than that in a smaller motor.

I don't think it's going to matter much what intake you put on it, it's really not going to make any significant difference.

 

3970020 is the casting and I have done research and you can bore a 020 Chevy 307 block to .125 safely. But that's the Max on this block. We had the heads pulled before I installed it and The bore measured in there at 4 in. And it does have flat top 2 valve in it. I was worried about it being bored that far so I spent a lot of time calling around and researching online. The 020 block has thicker cylinder walls then other 307 blocks

 

Here's a link about a 307 being bored out.125

 

OK so your compression is about 8.2:1 then. Whoopie!!!

Still isn't gonna matter much what intake you use. I'd suggest you keep it cheeeeep.

I've been "doing research" since 307s and 350s were NEW, mostly using wrenches. After all that was back before Algore invented the Interwebz. I wouldn't bore a 307 block AT ALL EVER back then, and I SURE AS HELL wouldn't do it now. As cheeeeeeeeeep and common as 350 blocks are, let alone the vastly superior LS type motors, just simply not worth the trouble risk and expense. Butt hay... if you've already got it, and it's already that way, go for it.

 

I wonder if the timing marks are accurate? Did the balancer slip at all? When you had heads off did you put #1 piston at top dead center and check to see if timing tab was correct?