Starting my engine build

[GRX]

Originally Posted by geezer#99

If you plan on driving it when the temp is below 50F, you might regret the air gap choice.
You need heat in the intake when it's that cool out.
Could be a tuning nightmare for you.

Good point. That intake totally eliminates the exhaust cross over. May mean having to keep your foot on the gas for 10 minutes or so to warm the engine before driving.

[Mrturner1]

This is what I got for the head bolts

[Mrturner1]

I've tried Home Depot, Riebes auto, Napa, and Harbor Frieght and nobody has a thread chaser. Would a clean head bolt with some brake cleaner do the same job?

[ptc]

Originally Posted by Mrturner1

I've tried Home Depot, Riebes auto, Napa, and Harbor Frieght and nobody has a thread chaser. Would a clean head bolt with some brake cleaner do the same job?

Just use a tap like stated before, a 7/16"-14 thread tap. I just saw this thread and read thru the whole thing. I see youre in Colfax, I have a very good friend that lives there, builds boat motors. Looks like you have been to Tognottis for your parts too, the guys there are very smart and helpful. Ask all the questions of them you need.

I have a couple questions - Did you verify what the SBC heads you already had on the motor were? springs? valves? specs etc? It looks like the PO went to a pretty good effort on the rebuild using a LUNATI cam, thats not cheap stuff, already had a double roller timing chain thats probably good, does the chain feel loose? Your heads, springs, valves were probably sufficient for the cam that he already went through the process of 'building'. Do the heads look like any porting was done or any work on them at all? Maybe they are shaved? to get more compression? did you check the deck measurement or ask the PO?

Also with the PO going .040 over on the pistons, shows he wanted something a little more than most. The pistons are flat tops but 'doming' them is not the only way to get compression ratio changes. There are many things to check when you start decking heads and such, you have to figure gasket quench thickness, chamber volumes, piston deck clearances and many others. it really is 'rocket' science if you want it right and want it to go fast.

The air gap manifold will be a good upgrade as will the new carb. I dont get the 50F number mentioned, as you want manifold temps to be AS COOL AS POSSIBLE, thats why intercoolers are used on blowers to make them even COLDER. Theres been alot of input here for you to take in. Just beware that there is A LOT of information out there.

I didnt see in any of your first posts as to why you wanted to make alot of these changes to the motor? Did you have any baseline of information on its performance other than it has a 'lumpy idle'.... you may be going backwards in your enhancements if you dont know where you started. Does that make sense?

Chances are if the PO knew what he was doing and there isnt many miles on that motor, you are doing alot of work for nothing at this point. just saying.... please dont take any of this wrong.

Try and get a 'build sheet' from the PO if you can... you might be pleasantly surprised at whats in your motor.

[Mrturner1]

I'm not sure how to tell if there's any porting or decking done to the heads that were on it, but here's a pic of them. The springs and valves must have been sufficient because it ran great. I think you're right about the PO doing some work to the engine, but I was looking for more out of it than it had. I wouldn't be surprised if it was a nice little 300hp motor at all. Needed a stall converter bad but ran like you whipped it after 3000 rpm.