UltraZLS1

iTrader: (13)

I had a set of heads milled that I bought off of these boards a month or so back and they were supposed to be the 64cc version.

Well he only took off 3 thousandths and then cc'd them. He came up with 58cc. And assuming they were clean up milled before. This must mean that they started as a 59cc head. Unless the guy actually took off 30 thousadths...which would put me around 58cc if they were clean up milled before...assuming 1cc off per .006 mill....dammit!!! I dont know what to do

I had them milled because they were scratched form shipping.

Does anyone know how I can tell what they started out as...like a part number?
If gunnar is around...would you know how I could find out?

The main reason I need to know is because I dont want to run into p to v clearance with my current cam in my sig...which I should have none since I am using the mls gaskets which are like .055 compressed and these heads have been barely milled. Unless of course they had the **** milled out of them before I bought them or the guy is a dumb *** and took off 30 thousandths instead of 3...

What would my compression ratio be running a 58cc head with the mls gaskets and a stock bottom end? Am I screwed for pump gas? It has got to be well over 11 to 1?

Thanks for the help, Troy

Gunnar@Patriot

iTrader: (20)

Look on the end of the heads for a 4 digit number. This will help us trace the information on the heads. Were these a new set or were they a second hand set?

The compression will be in the 11.2-1 range, this is with a 6.0 GM MLS .055" gasket, stock bore with the piston .007" out of the hole. This can be ran on 93 with a good tune.

calongo_SS

iTrader: (7)

compression will be about 11.5:1 w/ MLS gaskets, about 12:1 w/ .04 cometics

silverTA2002

iTrader: (1)

I'm about 11.3:1 and run completely fine on 93 pump gas for a daily driver (in case you're worried about that).

UltraZLS1

iTrader: (13)

They were second hand...but redone by you guys (patriot) with new valves, seals etc sometime in the past year and then sold to me. I dont see any number on the ends of the heads...only pat pen and co. The soft plugs have some numbers on them but I dont think that will help (numbers and letters and not 4 digit)
Anywhere else I could look?


Is this higher compression going to make the car run even worse without a tune? Because I have to drive it almost 2 hours to get the tune. The car ran fine with my 224 112 cam...So I dont know how much worse it will be with this cam, heads, and a lot more compression (over a full point more)

When I picked up the heads today I specifically asked him if he took off 3 thou or 30 and he said 3. He said they cc'd exactly 58. So if patriot took off 3 to begin with then it would work out. BUT...if you guys took of 3...then the previous owner took off 30...and then I took off 3...that would put them at 58 as well.

Im lost here

UltraZLS1

iTrader: (13)

ok I found some numbers near the end of the head right below where the valve covers mate. But they arent 4 digit

One head says 0611214
The other says 021120 and the last number is either a 9,8,6,0 or possibly a 3...It is hard to see

UltraZLS1

iTrader: (13)

Hey Gunnar...any luck with those numbers?

I was thinking...even if these heads have been milled .036...wouldnt my cam still clear using the mls head gaskets?

I know some people running 228 size cams with the afr heads milled .024 and a .040 cometic. and some others running the f13 with afr's milled .030 and the stock gaskets.All with no cutting. Seems to me that I would be right in the ball park with these guys with p to v clearance.

Do the afr's clear better than most heads? Any input on this?

What about the compression ratio here? I am coming up with 11.5 using this calculator and -.007...58cc http://www.rbracing-rsr.com/compstaticcalc.html

Is 11.5 too much for this cam? will it run ok?

Sorry for all the ?'s...im just paranoid.

thanks for the input

Gunnar@Patriot

iTrader: (20)

Those numbers are not the ones. If the heads were redone in the last year, they should have a 4 digit invoive number stamped on the end of the heads. PM us the customer's name and let us try it that way. We do have customers running 11.5-1 on 93 octane with a good tune, it can be done.

UltraZLS1

iTrader: (13)

Well they were re-done, everything is new on them. I pm'ed the guy I bought them from and he hasnt got back to me yet

thanks a lot for the help

Well if it can be done on a tune...how is the car going to run on the way to the dyno? Will I even be able to get it their?

Looks like im sol.

SideStep

What type of F13??? Not the 112+4. Alan Futral quoted .086 on the intake side with 62cc AFR205s and the FACTORY head gasket. But this is apples and oranges and should really not be used to compair with your heads. FYI, AFRs do have slighty better clearance compared to factory LS1 castings.

You have clearence issues. You are not going to know exactly until you mock it all up and measure. 228/230 XE-R on a 112lsa I just don't see it happening with out fly-cutting (no big deal). Just measure and know for sure...

EVEN if it cleared, on the issue of pump gas you are screwed... When I work the numbers for your current cam I get a DCR of 9.04. Forget the static compression your DCR will tell you what kind of gas you will need. Assuming:

.007 out of the hole
.054 composite factory head gasket
non fly-cutting
58cc heads

Even if your fly-cuts came to 2cc it would still leave you with a DCR of 8.8

Be prepared to pull some timing or run race gas... OR you could retard that cam 2 degrees and it would drop you to a DCR of 8.66 (with 2cc from fly-cutting)... This would be a sweet combo in my opinion!!!

228/230 112lsa +2 (110ICL)

__________________________.006__.050 (lift)
Intake Valve opens - IVO_____28.5___4
Intake Valve closes - IVC_____68.5___44
Exhaust Valve Opens - EVO___73.5___49
Exhaust Valve Closes - EVC___25.5___1
Exhaust Centerline - ECL______114___114
Overlap ____________________54____5

Good Luck,

GuitsBoy

iTrader: (4)

Measure the deck height. My stock LS1 castings were right at 3.750" if I recall. That should let you know if they were milled .030 or not.

UltraZLS1

iTrader: (13)

How do I measure the deck height? thats a good idea...thanks

Also...how would I retard the cam 2 degrees (adjustable timing chain?)? I didnt really want to do this because I didnt want to rev the cam very high ( I want to shift around 6500)

Also...my clearance issues will be only if they were milled .036 correct? It shouldnt be a problem if they started at 59cc, since patriot adds to the chambers to increase compression.

Couldnt I have someone take some out of the chambes to lower my compression as well? SIDESTEP...if this will work what cc would you suggest for optimum output on pump gas...keeping the cam at a 112 plus 4??

I really appreciate the help guys

this is getting worse by the second.

GuitsBoy

iTrader: (4)

Check the deck height with whatever youve got handy. A surface plate and height gauge, a micrometer, even vernier calipers would work.

You need an adjustable timing chain to advance or retard the cam timing. Retarding will only make the powerband higher inthe rpm range. You want to advance the cam to bring the power band down.

Yes, if theyre not milled, you shouldnt have clearance issues.

SideStep

Yes you would use an ajustable timing chain to retard the cam...

As far as taking material out of the chambers shoot for 61-62 cc (8.7 - 8.59 DCR), good luck...

You mods would equal:

CC__DCR
61__8.7
62__8.59
63__8.49
64__8.38
65__8.28

UltraZLS1

iTrader: (13)

Is taking material out a bad idea? or would it probably be costly and time consuming?

I might just sell these things now, and my car is entirely tore down...oh man.

Where exactly do I measure the deck height (from which point to which point)

I have a general idea but im not exactly sure where the deck is...im kind of a newbie when it comes to cylinder head stuff

A dcr of 8.7 is as high as one should go on pump gas I am assuming?

thanks again for the help, I would be screwed w/out you guys ( or more than I already am)

Xtnct00WS6

iTrader: (8)

I'm pretty sure that the deck height measurement is from the the top (where you put the valve covers) to the bottom (the surface that would have been milled) Someone correct me if I'm wrong cause I'm not 100% on that...

8.7 should be fine but I wouldn't go much more than that personally.

Gunnar@Patriot

iTrader: (20)

We measure at the end of the head. From the top of the valve cover rail to the deck of the head, at that particular location is 4.750" on an unmilled head.

UltraZLS1

iTrader: (13)

Well I have some good news for once.

I measured them with a digital feeler gauge and came up with 4.74xx every time.

So theirs no way they have been milled .036. These must have been 59cc to start with correct?

I guess my next step would be to have the combustion chambers reduced ( take some out)? I am gonna want to put them right at 62cc. Im not feeling very lucky right now so im not gonna push it with 61.

Gunnar...have you guys ever had to do this? would it be a bad idea (hurt performance etc?) how much would it cost me? I figured if you guys add to the combustion to gain compression...you surely must know how to take some out effectively...and I would rather send them to you guys and have it done right...im done taking chances.
Let me know what you think

I feel a little bit better now...but it is still a PITA dealing with all this crap.

Im gonna have to thank you guys again...you really saved my ***.

UltraZLS1

iTrader: (13)

Running through my search I have found a couple guys that pushed the envelope and ran a 9.0 DCR. Most said that a good tune could clear up most problems. slow trap is one of them that says he had a 9.0 DCR

Some other posts said that 8.8 was the limit.

hmmmm

Gunnar@Patriot

iTrader: (20)

PM Sent.