I have a used H/C pakage I got off of another member. I sent the heads to TEA to get checked and flowwed. They said they flowwed like 295/225@ .600 and the chambers are like 59cc's
The cam that came with it is supose to be a 232/240 @ 595/608 on a 114+4. But the cam # is ground off the end of it. So I'm going to send it in to get tested as well. To make sure it is what they say.
Correction on the cam, I sent it to comp and its a 234/242 591/601 114lsa.

I'm not sure what gasket size to use. I need help with that as well.

How much fly cutting will be needed with X gasket?

I also have a new set of comp lifters. But with the bad press these are getting now, I may get morrels or new stockers, and sell these new comps.
Any sugestions would be great.

 

i was runing a .607/.608 with stock heads/pistons... no fly cutting...

 

well thats great dude, but obviously his heads arent stock lol, so that wasnt much help at all.

i think your going to need to flycutt, at least on the exhaust side

 

why would that matter?

 

Because the heads are 5.3's with 58cc chambers. The ls1 heads have 67.xxcc chambers. so the heads I have are milled about .030".

I called TEA this morning and they said about .080 to .100 fly cutting may be required.


If I were using stock heads they might not need fly cut?
Maybe I should be using stock ported heads with no milling. But I want a bit more comression. I'm running n2o.

 

ahh see u never said they were milled.
stock ported heads (no milling) u will clear just fine.

yeah im running 4.8L stage 2 heads. because of the juice. (going from a 100 dry to 250 wet)
compression with the -2cc pistons is about 11.1 to 11.3 to 1

but ive seen plenty of guys with stock pistons/heads clear .612 cams all day long. and i did that with my .607 for years.

 

Cam looks like a G5x2 doesn't it? Is that what you were sold?

 

Yes, it's a comp grind. 232/240@ 595/608 on a 114+4. I need to get it doctored to make absolutely sure thats what it is.

I want to use the 5.3's I have with it. But I'm a little scared about cutting the pistons.

 

Dude seriously think about reading for a few days and learn before your next post. I am not trying to **** you off or anything but the comments you made show your lack of knowledge.
Hell if you want I will even take time out of my day if you want to call me and explain some of this stuff to you.
I just hate seeing wrong info being posted.

Just to clear the issues up in this thread.
58/59cc shows that the heads have increased compression.
The way the head (in this case the 5.3 head AKA the 4.8 head) gets the higher compression or smaller cumbustion chamber is typicially by milling. (Excluding PP and ETP)
Also when larger valve are used even if there were no milling done if makes for less P/V clearence.
Now larger valves wernt brought up but most ported heads recieve larger valves and a valve job.
Plus we haven't even brought up the fact that the 5.3 untouched will give slightly less P/V clearence then the LS1 casting head.

Next I want to inform you that lift have damn near NOTHING to do with P/V clearence. That is a common thing many are mislead into thinking.
Under the right conditions a 750 lift cam will clear with stock heads and without flycuting.
Again, I am not trying to be rude or make anyone mad.
Just trying to help out.

 

lol so am i wrong for saying the the smaller combustion chambers on the 4.8 and 5.3 would increase compression?

 

Will I need a shorter push rod?

 

Nope your right there.
The smaller CC will increase compression.
Follow the link in my sig if you want to run some different numbers and find out what cc head makes what compression.
As a rule of thumb.
Enter 0 for piston dish or dome as we have flattops.
If you have valve relives enter 2
Also normally LS1's have a piston that is a -.004/-.007 I normally run my figures when not knowing the exact amount using a -.005
Make sure the - is there or else the compression can be almost a half point difference.
Gasket thickness should be .054 for a stocker.
Bore is 3.898
stroke is 3.622

 

I got the heads back today from TEA. And they are 59cc chamber.

With a stock gasket size, what compression would this yeild?

Here is the flow #'s.
.100 67.2/56.1
.200 138.3/109.6
.300 200.0/158.2
.400 247.0/ 205.1
.500 296.5/250.9
.600 295.3/258.3

Is this pretty respectful?

 

thats strange,i bought a used g5x2 from a member and it also had all the numbers ground off.(lg grinds off comps numbers)so i sent the cam to comp to get them to doctor it.havent got it back yet to really know what i bought,but good luck.btw maxwell at comp will do it for free.

 

Measure it dude. You aren't going to get an exact number from a bunch of strangers guessing. To many variables involved to trust internet racers opinions. Go with the thinner Cometic head gasket at around .040 - .045 to get a better quench. Stick with new stock lifters or stock replacements unless you plan on switching to adjustable rockers. Most do cut around .080 to .100 average. The more you cut the more you lower compression, but does allow for future cam swaps without cutting again. Don't trust strangers guessing for you, it's to expensive of a mistake if they guess wrong.

 

Man, i was in the exact same boat you are in, except my 5.3's were not milled, just cleaned up .008. I was told it would be too close for comfort with the g5x2, so i pulled that cam and got a futral custom grind 232/236 .599/.603 on a 114+4 lsa. allan told me that with the +2 it would be a chance it would fit, but not a good one, i was very impressed, stayed almost the same as the g5x2, but just changed the lsa a little and it fit fine. not sure if it helps, but i feel your pain dude

 

Really! Do I just call there and ask for maxwell?

 

I sent the cam in to comp and it is a 234/242 591/601 on a 114. I wish the lift was a little bit higher but I think it will do just fine.

Anyone with this size cam? How do ya like it?

 

Hi,

might be apples/oranges, but I'm doing AFR205cc (59cc) with .040 Cometics and changing out an LS1 Hotcam for the G5X2 - have been told by LG - "no flycutting necessary". BUT, these are definitely NOT 5.3 heads....just letting you know what I'm hearing....

Pay attention to the head gaskets your thinking of using when questioning flycutting....

 

Thanks buddy. I sent it to them and in fact it's a 234/242 591/601 114lsa.
Looks more like an X3 with a little less max lift. It should kick ***. I hope!