I would like to get some opinions on the following.

Current setup:

Cylinder Head Volume: 76cc
Piston Head Volume: 10.00cc
Gasket Thickness: .039"
Gasket Bore: 4.125"
Cylinder Bore Diameter: 4.00"
Deck Clearance: .045"
Stroke: 3.48"
Rod Length: 5.7"
Intake Closing Point: 60*ABDC

According to the Keith Black calculator, the static compression ratio is 7.906 and the dynamic ratio is 6.582.

Here is what the setup will be once I install the new heads tomorrow:

Cylinder Head Volume: 64cc
Piston Head Volume: 10.00cc
Gasket Thickness: .015"
Gasket Bore: 4.100"
Cylinder Bore Diameter: 4.00"
Deck Clearance: .045"
Stroke: 3.48"
Rod Length: 5.7"
Intake Closing Point: 60*ABDC

According to the same calculator, the static jumps to 9.287 and the dynamic to 7.699. Am I going to see any difference in the way this motor runs? Thanks.

Yes.

yes
(especially if the new heads breath better.)

They are AFR 195 street eliminators. Can I expect about 50hp/ftlbs at the wheels? Does compression have any effect on how an engine starts? I ask because my engine requires a couple of revolutions before it fires, where some of these high horsepower motors I see fire off almost as soon as they turn the key.

What heads did you have on it before? If they were factory heads then going to the AFRs even without a compression change would make a huge difference, You are going to be very happy!:thumbsup:

Are your pistons really 45 in the hole???

The original heads are an OEM 76cc chamber smog style head. 1.94/1.5 valves and an open combustion chamber. As far as how far the pistons are down in the block, I am going by what the manufacturer says. I went on the Sealed Power website and they say the piston I have has a deck clearance of .045". I don't think the block has been decked so I believe this measurement is correct.

It is possible to run a FelPro 7733SH-1 on AFR heads, right? This is the steel shim, .015" thick gasket. Thanks.

Sealing is the issue here, sometimes if you have a course cut on the block or head, its hard to seal. I have heard of guys using these shims but I would have a hard time saying that it will work. Any chance of finding some of those Kometic (sp) gaskets?
Basically your quench will be .060 at best . This is not the best but if thats all you can do, then thats it. I personally would deck this block to 0 and use .039 composition or so gaskets. But thats just me.
Your tighter quench prevents detonation plus you have alloy heads now, you can get away with a higher compression.

The thinnest composite gasket I found when I was looking for good quench and sealing with lite aluminum heads was a fel-pro .025"
Good sealing, no issues.
Could you get the heads milled to 70 or 68cc's?

The thinnest composite gasket I found when I was looking for good quench and sealing with lite aluminum heads was a fel-pro .025"
Good sealing, no issues.
Could you get the heads milled to 70 or 68cc's?

Will help compression but still does not help quench. Not sure what Charlie wants.

These work fine with aluminum heads...http://www.jegs.com/i/Fel-Pro/375/1094/10002/-1 Aren't most stock pistons around .025 in the hole without decking the block?

You need to measure the piston deck height. Production tolerances vary a BUNCH on factory blocks so what the manufacturer says about a particular piston is a guideline at best. Mine was .032 down on one side and .038 on the other before I decked it.

Better safe than sorry....

I'm only commenting on the gaskets! Markw is right, the Fel-pro 1094's are great. They are shims but they are embossed and coated with a black sealant. I've run these on blocks and heads with a "questionable finish" with good results. (No leaks!)

Will help compression but still does not help quench. Not sure what Charlie wants.
Yep you are right, dang it would really help if that block could be decked to .015 or lower, .025 or .015 would make for a good quench and good comp ratio.
As said before, the heads breathe better than stock, you will see a diff, even with a little bump in compression you will see even more of a difference.
I don't understand why they had so much deck on the blocks and used such thick gaskets on stock motors... Then again, as all engineers think, not everyone wants to hot rod.

I found the pistons are flat top. The heads are brand new AFR 64cc chambers. The block is perfect as far as finish and the heads are great(brand new). I used the 7733SH-1. Followed the AFR torque recommendations to the letter.

Well, I just finished everything and let me tell you, this thing is a screamer. I do have one question, do you need to retard the timing when you increase the compression? With the old set up, I was running 18* initial and 36* total. With the setup I simply reset everything to where it was before.

One last thing, I saw some bubbling just to the left of the lower head stud. The stud that sits under the #1 header tube. Does this mean I am going to have to pull everything apart again and change the head gasket on that side or do aluminum heads require a retorque after a few heat/cool cycles? Thanks.

It is advised to re-torque after a few heat cycles.
When you run more compression, higher octane, and especially power adders such as nitrous & forced induction, you should retard the total timing & the ignition curve.
18 initial and 36 total isn't too bad, if it isn't pinging or leaning out, I wouldn't worry about it.
I would be a little concerned about the bubbling... Usually you see a little oil around the gaskets on the first start up, but bubbling would be a red flag for leaks.
Did you run the motor with different heads after the machining and then put the afr's on with the shim steel gaskets?

Charlie, I got some goo out of one stud also, coming up around the nut and washer. I sealed my tread studs with Permatex so I suspect this was a heat expansion thing as it did quit.

As for the timing, you may listen to your motor for detonation. I am 17* inital, 36 total. Screamer it is, 7200 comes up pretty quick.

Don, my bubbling is coming from between the head and block right under #1 header tube, but what I do remember is that I forgot to put moly lube between the nut, washer and head surface so the torque readings were probably off. I am going to remove all the nuts today and apply the lube and retorque.

I also have a rapping sound coming from under the valve covers. I pulled the covers and ran the engine and it's still there. It sounds like the rockers hitting the rocker drippers that are on the covers, but it's still there even with them off. I thought it may be pinging, but since I have never heard pinging, I don't know what it sounds like. Before I ran 87 with Octane Supreme 130. This is a true tetraethyl lead substitute to bring it to 89 octane. Yesterday I went to sunoco and put it 5 gallons of their 98 octane. My tank was on a 1/4 so I thought by adding 5 it would help, but that must not have been it either. Today I am going to redo all the rockers. Do you have any suggestions? If it was valves hitting the pistons, it would lock up or shut off because of damage, right? The block is standard deck height and the heads are stock out of the box. I have at least .025" piston dome height and the .015" shim gasket, plus whatever height the valves sit up at on an AFR 195cc street head? If it was piston to valve contact, the motor wouldn't continue to run.

John, the motor was not run with different heads before the AFR's, but like I told Don, I forgot to add the moly lube to the washer before torquing.

Can someone calculate my compression for me? I put in the specs I have, but I want to make sure I am close.

64cc head
.015" gasket thickness with a 4.100" cylinder bore
4.000" block bore
rod length 5.7"
stroke 3.48"
flat top pistons w/4 valve relief
Comp 270H-10 cam
This block has never been decked so the deck clearance should be .025"
The only thing I am not sure about is the intake closing point of the 270H.

Using the Keith Black calculator, I got a static of 10.263 and a dynamic of 8.488

Thanks.

Well, I got everything together and now I have what sounds like a lifter going bad, but why out of the blue? I never had an issue with the old heads. Here is a video of the noise I have. Upon initial running, the noise was BAD and coming from both sides. Yesterday I removed the rockers to retorque the heads and upon reinstallation and setting of the valves, the noise is now only on the drivers side. Please note, I have Rhoads variable duration lifters that require them being adjusted like a solid lifter. I set them using a .020" feeler gauge, which is the street setting.
http://i61.photobucket.com/albums/h69/charliek3006/th_MotorNoise.jpg (http://s61.photobucket.com/albums/h69/charliek3006/?action=view&current=MotorNoise.flv)

Can pushrod length have anything to do with this? I used an OEM length rod with is shorter than the rods I used when I installed the roller rockers. The rods that came with the roller rockers are 1/8" longer than a standard rod.

well, the new heads might have stronger springs... so that could create some concern... unless you used the same valves...

could also be an exhaust leak sounding like a lifter...
header bolts are known to come loose... so check those first and look for traces of carbon.

good luck

A

I am hoping I found the issue. I pulled the cover on the drivers side and noticed a mark. It appears a rocker was contacting the cover.

I have those same valve covers on AFR heads and they do hit like crazy. I had to clearance the inside of that thick ole valve cover in about 16 places.:yes:

When a piston company says the dome volume is -5(speed pro part #H345NCP40), does that mean all 4 reliefs total 5cc or each relief is 5cc's equaling 20cc? The keith black comp ratio calc wants a piston head volume. Do I enter 5 or 20? Thanks.

I downloaded the CamQuest program from Comp Cams. How accurate is the hp/tq ratings it gives?

I have those same valve covers on AFR heads and they do hit like crazy. I had to clearance the inside of that thick ole valve cover in about 16 places.:yes:

Same thing on mine with eddy heads...many, many grind marks on the insides of my valve covers.

Does increasing the compression help with gas mileage? Doesn't higher compression make the fuel burn more completely, thus requiring leass fuel to accomplish the same results or am I way off base here?