chris mac

ok... here's the deal... i've got a 99 SS that i'm doing heads/cam on.
my set-up is as follows.
brand new bare 243 castings from Patriot milled .010 ,with stock LS1 valves.
918 springs
LS7 lifters
TSP 7.4 pushrods
TSP 231/231 .595-.595 112+2
Mr. Gasket .040 head gaskets

when i was researching this combo i was under the impression that all these parts would work well together, but when i went to check the ptv my valves were hitting! i did some talking to some friends and a buddy suggested some 7.35 pushrods. i installed them and they helped (i could atleast get full lift from the valves) ,but they still pinched the clay in half.
is notching the pistons my only option?
or would a custom cam be a better route?

i'm open to any and all suggestions!!!

thanks

mac

Xtnct00WS6

iTrader: (8)

I'm not surprised that you have issues with that cam and milled 243's.

You can measure like this, or use a solid lifter and clay.

EDIT...Did you have a solid lifter in place? You should't change pushrods to compinsate for piston to valve clearance. You should have them within spec and go from there.

chris mac

it sounds like i need to do alot more reading!!! i just used the LS7 lifter and clay.
would i be better off to get a custom cam?

thanks for the info...

mac

brad8266

iTrader: (23)

either change cams or try a .050 gasket. My 232/236 .575.581 112 with milled 5.3's would not clear either if i didnt have the -2cc pistons, but my heads are like 57 CC, compared to yours that are like 64cc

chris mac

a buddy brought a stock gasket by last night just to check, and it wouldn't give me enough clearance to be safe. with the 7.35 push rods and the .040 gasket, the valves are still making contact with the piston. they're just barely hitting.
i'm stuck between fly-cutting and a custom cam...
would a custom cam be more beneficial to my setup?

mac

brad8266

iTrader: (23)

I dont understand how that setup is even hitting in the first place. Is that cam installed properly? Those heads are only milled .010, thats only like 2cc's, you should not be having PTV issues with those heads milled that little bit with stock valves to boot.

I have a bigger cam, way smaller combustion chambers, way bigger valves, and I still cleared with over .120 clearence.

chris mac

straight up... dot to dot...
Gunnar from Patriot told me that it would work. that's why i had him mill them .010. he actually told me that i could get away with .020 and probably still be safe.
probably just end up fly cutting unless someone can suggest a cam that'll make good power/torque and will clear with no probs!!!

thanks

mac

1baddls1

iTrader: (31)

personally i say junk the mr gaskets... what bore are they also... not 3.905 or 3.910

2ndly just installed...
TSP Torquer II (232/234, .595"/.598" 112 +0)
243's on milled to 60cc (.020 mill)
stock MLS gask ~.053

NO PTV ISSUES... i think you have some other issues... go back to the drawing board and triple check EVERYTHING

Xtnct00WS6

iTrader: (8)

Just to let you know a .020 mill will be closer to 62cc's not 60.
.020/.007=2.85 64.45-2.85=61.6
I'm a hairsplitter...I know
https://ls1tech.com/forums/showpost....2&postcount=41

I'm surprised your setup cleared if you have aftermarket valves. How much clearance did you have?

chris mac

i'm pretty intent on keeping the .040 gaskets for the quench they allow. they're 3.97 bore, i believe. many reputable members have recommended them so they should work well. i'm probably gonna pull the motor since everything is out of the way and just fly cut the pistons. that'll allow me to run a pretty wide range of cams and i'd be able to better optimize my setup...

still undecided, though

thanks

mac

brad8266

iTrader: (23)

Are you sure you got 243 heads and not a set of 5.3's? Sorry to ask such a siomple question but I just had to check. I just cant understand why you are having PTV issues.

1baddls1

iTrader: (31)

stock valves

that was my F up - mine are 62cc his are 60cc (from the invoice per Patriot)

.005 mill is 1 cc on a gm casting so now im confused

1baddls1

iTrader: (31)

2nd that

anythings possible

BROKEN

iTrader: (7)

seen the heads in person they say 243 on the casting number

Xtnct00WS6

iTrader: (8)

The link I posted says it's .005 for the block deck to = 1cc of volume. It's .007 for the heads.

brad8266

iTrader: (23)

.005 is 1cc according to one of the sponsors here. Dont remember which one it was though, lol.

Irocss85

iTrader: (1)

just fly cut the pistons. its not hard. just time consuming. I rented one from LG and they were great about it. make sure and ask for the exh. cutter if you need to cut the exh. side like i did. my cams diff. then yours. also, I am a believer that even with light checking springs (you did use thin checking springs on your vavles right?), you need to use solid lifters for the clay test. then add the preload depth to the thickness of the clay cause the solid lifters will be at 0 preload.

however, I too am suprised you ran into clearance problems. Id degree the cam to make sure the cam isnt more advanced then advertised. could be due to other things then just the cam too. ie.chain, placement of the key. my cam was perfect, but one I checked was 3 deg. advanced from the cam card, and that could explain alot if thats whats goin on with your setup.

JPH

iTrader: (2)

pushrod length should not have made a difference, and yes you should flycut instead of grinding a new smaller cam. try retarding your current cam, thicken the head gaskets up, these will all help. what was you ptv clearance?

BOWTIE

Are you compensating for lifter preload? Keep in mind if you are saying you have 0 clearance but the lifter plunger is fully expanded (against the retaining ring), then once you compress it .060-.100 that will affectively give you .100-.170 p/v clearance. This is one reason I do not know how people are checking these with the clay method unless they have a lifter converted to a solid with the plunger already collapsed to the depth they intend to run (.060-.100 is the normal given range). Also if you check it witha regular lifter and the regular springs, the lifter will bleed down and give you a much higher than actual indication than what is accurate. That said, I agree with most of the people on here that question how you could be having p/v issues with that setup. I mean guys are running the MS4 and Trex's on stock 243's with stock valves, I find it hard to believe that that .010 mill make them hit with that size camshaft.

JPH

iTrader: (2)

he is using -.011 thinner head gaskets, but agree with what you say.