[dsfordguy]

Hey heres one for anyone out there. What would be the best power building combo i can go with without decking the block? I'm looking for cam, intake, stall, gear, valve spring combination. The reason for not wanting to deck the block is that a few years ago i bought a reman short block cleveland for my 72 gran torino and it has only accumulated 5000 or so miles. im going to look through it while it is out but if everything is ship shape i dont really want to disassemble the short block assembly in order to get it decked.

Second, if i can run a pretty nice solid flat tappet cam cam without decking the block I will prob get the heads milled for guide plates and screw-in studs( wallet willing). Otherwise i will prob go with a pretty nice hydro set up with the crane conversion kit.

I'm pulling the motor this wednesday and i'm going to totally confirm that i have the closed chambered heads and not the open. I'm pretty sure that I remember having the quench chambers but i"m not 100% sure so for now we will discuss setups for a closed chambered motor hopefully i don't run into a disappointment of having the open chamber heads.

Ill be glad to here anyones input. Thanks guys

 

[ScreaminC]

Whether or not you deck the block, and whether or not you have quench heads, MEASURE your compression ratio. Then figure out what your goals are (street, street/strip, strip).

Knowing what your compression will be and what your goals are, the exact buildup can be determined.

 

[dsfordguy]

Well if I pull the heads and find out the cc's of the combustion chamber I should be able to figure out the compression ratio right?

2nd- how much lift can i have on a cam without decking the block and without having valve to piston clearance problems?
Thanks

 

[ckelly]

You can measure that too. But it'll be quite a bit on a short block that isn't decked. However, most solid flat tappet cams for the 351C that have a lot of lift will have a lot of duration. If you do not have the compression to support a lot of duration, you'll just make the motor run like a sad dog. Measure what you have, then talk to Crane and some others and see what's recommended. you leave a lot of efficiency on the table if the quench clearance is too large. Probably the Crane 238/248 solid is the biggest you'd want to stick in there.

 

[dsfordguy]

K I found out that i have the open chambered heads for sure so what would be a good setup for the open chambers?

The open chamber compression is about 9.5 right?

Thanks

 

[ScreaminC]

Personally, I wouldn't bother building a 9.5:1 4V Cleve. Buy a set of 2V's or find a way to get some compression. You could probably sell the 4V's to buy a set of 2V's.

 

[ckelly]

Hey, mine's only 9.3:1!

OK, if you're not going through the motor and they are stock uncut which would put them around 74~75 cc, you're looking at 9:1 at the most. For that, I'd use a 214/224 hydro cam - tops. And a dual plane intake - the new Air Gap is probably a good candidate. There's not enough compression to run much bigger. Overcam it and it will be a slug.

 

[dsfordguy]

What could i do to get to 9.5:1 compression? would gettin the heads milled do it? What was all done to that open chamberd 4v that you said was ur first one? Could i build something like that without going through the short block or no?
Thanks Ckelly

 

[ckelly]

If you run Oc heads, then you HAVE to zero deck the block if you expect to get any detonation resistance at all. you need turbulence and you're not going to get it with that big chamber and the piston .050 or .060 down in the bore. Then you'll need to cut the chambers down to 72 CC. That may be as much as .020 or .030, hard to figure - more of a try it and see.

 

[dsfordguy]

okay I really wish that i had those closed chambered heads i thought i had. What would you do in this situation? would you consinder doing the work required to run the open chambered heads or would you get a new set of heads? The problem is that my wallet is not very large.

I also have a 78 460 with a c6 tranny. But that motor will probably require new heads too.

Thanks Ckelly

 

[dsfordguy]

What compression ratio would i be looking at if i got the deck zeroed and got the heads cut down to 72cc's?

Thanks Ckelly

 

[dsfordguy]

okay, im taking the block to the machine shop tomorrow to get the block decked and i'm going to get the price on what its going to cost to get the OC heads cut down to 72cc's. What kind of compression will i be looking at? Will the motor still run safely on premium 92 octane?

 

[dsfordguy]

It turns out i have some good news for once. I got ahold of a pair of closed chambered heads which i will have in two weeks. So back to the closed chambered build.

Should i get the block decked while i have the motor apart? How will getting the block decked benefit me? higher compression? detenation prone?
Will i still be able to run a nice cam with the block decked?

 

[ScreaminC]

OK, you've got some quench heads. That's a great start!! Now, I wouldn't worry at all about zero deck. You'll have enough compression to run a nice cam.

I'm not real familiar with what this will figure out to be for static compression.

1. Flat top pistons?

2. 2 valve reliefs or 4 valve reliefs?

Let's see... quench heads are what? 64 cc??

OK, lets get a guru here to give us a rough compression ratio.

Regardless, I would highly recommend your first step being to have the heads machined for screw in studs so you can run adjustable rockers. If you want, you can run the conversion kit. I ran it for a while and disregarded all concern on maximum cam size and maximum RPM. It never failed me.

So... figure compression ratio, decide on rocker adjustment, then we start to build a motor!!

 

[dsfordguy]

okay, thanx alot. So will this motor be detonation sensetive without getting it decked?

The motor has stock flat top pistons with two slight valve reliefs on the outer edge it looks like. From what I have read in my ford book my compression should be roughly 10.3:1 with the 62.something cc combustion chambers.

Is there any other prep machine work that i should worry about before we start?

 

[dsfordguy]

To correct what I just said in my last message. The book actually says the 4v DOAE heads have 62.8 cc's and 11.0:1 compression

 

[ScreaminC]

The heads will vary some in chamber volume.

I would say get the rockers adjustable and the machine work should be good to go. Unless you want to spend some cash on a good valve job.

Now, how much do want to spend on a cam? Can we go with a small roller? Or do you need to stick to a solid cam?

 

[dsfordguy]

probably 300 max for the cam. Do you have any idea of what its going to cost for the machine work to accept screwin studs? The crane conversion kit is not for solid cam correct?

What can I do to find my actual compression?

 

[tjcrawfo]

http://www.rosspistons.com/calculator.php

I use this for compression calculations, just measure the necessary information and enter into the calculator.

 

[dsfordguy]

I'm prob looking at spending 300 on the cam. I like the crane 521141 solid cam. what valve springs would be good for this application? I found that my compression ratio will be between 10:1 and 10.5:1 according to the compression calculator at ross pistons.com.

What do I need to tell the guy at the machine shop to do to make my heads accept the screw-in studs for the solid cam? And just out of curiousity what is an estimate of what it would cost to bore the cleveland .030 over? Can i bore it .030 and still have safe cylinder wall thickness?

In spite of the port mismatch can the Ed rpm air-gap work with this cam? (Need dual plane intake for the heavy car)
Is this build going to work okay with my HEAVY car?
Thanks Guys give me your input

_________________
1972 Torino 351c

<font size=-1>[ This Message was edited by: dsfordguy on 5/27/06 1:12pm ]</font>