Need HELP! please please!!g5x4

[SSdimension]

Originally Posted by LSX Truck

great cam! make sure u have the accessories to go with it

Thanks

Originally Posted by tim99ws6

You need to go to GM, and get a set of "MLS" head gaskets. Just ask for head gaskets for a 2002 Camaro Z28 and they should sell them to you. Or buy them from a distributor/sponsor---> I prefer Speed Engineering.


Username is "Speed Engineering" or website Speed Engineering?




Don't run crappy auto-parts stores version of head gaskets, and make sure you get a new set of bolts. They are stretch-to-yield. Once they are used once, they will never work again(as you already know now).

I dont know if they were crappy. They were from a company that makes gaskets but im not sure whats the thickness of it. Do you know GM gasket stock thickness??

Originally Posted by Slow 346

A stock replacement gasket from the parts store dosent necessarily mean its the same thickness as a stock GM one. Get a stock GM gasket to be safe.

Do you know GM gasket stock thickness??

Originally Posted by ws6_bandit

I have g5x4 and stock heads. Installed mine dot to dot and no problems. PTVC is very close tho. Im pretty sure valve drop between ls1 and ls2/ls6 is pretty much the same. You must be off a tooth or you have the wrong head gasket.

How did you check you PTVC? Is there a tool that I can use to find out how much clearance I have to work with. I rather not risk it and go buy a smaller cam instead. What kind of numbers did you put down in the dyno with that cam???

[FBodyPerformer]

I thought the G5X4 was too big for stock heads? The X3 was as big as you could go for stock heads with no PTV clearance issues? And even then you have to run a cometic gasket w/ a .040"?

[1SLwLS1]

stock gasket thickness is 0.052 crushed, when you order, it is normally referred to as 0.060.

I think the proper way involves putting some soft material(clay maybe?) on the piston top and running through a full cycle. Measure the thickness of the clay. Something like this, do a search for checking that clearance, there was a big thread about it.

[tim99ws6]

Originally Posted by 1SLwLS1

stock gasket thickness is 0.052 crushed, when you order, it is normally referred to as 0.060.

I think the proper way involves putting some soft material(clay maybe?) on the piston top and running through a full cycle. Measure the thickness of the clay. Something like this, do a search for checking that clearance, there was a big thread about it.

That is the correct "Clay" method. Simple and easy work.

[PREDATOR-Z]

Flycut 1cc on intake, and be safe. Also you should degree your cam (Louis has to give you the info for that)

[Thimble]

Originally Posted by JPH

Its a 240/244 113 cam.

No, actually it's on a 111 LSA.

My X4 cleared with stock heads/gasket...but as best I can figure, with only about .040" clearance to the intake valve. I put about 2000 miles on the car when it was cam-only.

I replaced the heads a few months after I put the cam in, and there were no marks on the pistons.
The heads that went on were milled .025", have a larger 2.02" intake valves, and I used a .040" gasket.

Since all of that killed the little clearance I had, I cut .110" deep notches in the pistons for the intake valves only to achieve approx .090" p/v clearance. I found exhaust valve clearance to be fine, no notches were needed.


I would just flycut it and be done with the issue. (ina addition to double/triple checking your timing chain is on correctly). Even if you found no contact, there would be very little clearance anyways.

[G Engines]

what you can do is buy an adjustable timing set and retard the can when you retard a cam you gain pv on the intake but you loose pv on your exhaust. some race engines require this to be done even if its not ware you want the can installed. you can run them as tight as .050 on your intake and .100 on your exhaust.

[BADD SS]

IMO people who buy a cam as large as a g5x4 and try to just throw stuff together, shouldnt be doing this in the first place. It could be mis aligned, not dot to dot, a stretch would be the cam ground off, but it happens, head gasket could be thinner. Lots of possibles. You must check to make sure its aligned right, degree'ing is kinda a neccesity IMHO.. Check your ptv, if its way off still with the right head gaskets, and the heads arent milled, get the cam cam doctored, it costs $50 around here.

[JFM-jr]

I am running this camshaft currently. 5.3 heads milled 23 thousandths and a 2.08 intake valve. Using the GM LS2 MLS gasket I flycut 60 thousandths to achieve the valve drop figures LG suggested. I have always found the tech support there excellent for stuff like this.

[s346k]

you might try simply retarding the cam 4*. that will free up some ptv.

i would use this opportunity to mill the heads and cut reliefs in the pistons. a cam that big would like more compression.

[1SLwLS1]

Originally Posted by s346k

you might try simply retarding the cam 4*. that will free up some ptv. the 243 heads offer slightly more clearance than ls1 heads.

i would use this opportunity to mill the heads and cut reliefs in the pistons. a cam that big would like more compression.

how so?

[s346k]

Originally Posted by 1SLwLS1

how so?

they don't, i am thinking of trickflow heads. i have too many windows open hah.

[SSdimension]

I got everything bolted up now. I turned the crank bolt and it does not seem to hit. I might just change the head gasket to a gm headgasket just to be on the safe side. Its dot 2 dot now and it should be ready to crank. I will let ya know how it went. Thanks for the info guys. Any more info will be appreciated. Antonio.

[JFM-jr]

So what was the changed by you that free'd things up? I cant see the head gasket being the main issue (not a bad idea to use the GM gasket anyway), were the timing marks off?

[SSdimension]

Originally Posted by JFM-jr

So what was the changed by you that free'd things up? I cant see the head gasket being the main issue (not a bad idea to use the GM gasket anyway), were the timing marks off?

The guy who built it said he fly cut the pistons. The headgaskets that I bought might have been thinner than 0.0052. So I rather be safe then sorry. What could be the worst possible if the pistons hit the valves?

[JFM-jr]

Well I can tell you if the head gasket thickness was causing PTV contact then you dont have enough PTV clearance in the first place no matter what gasket you use. Secondly turning a motor over by hand without any signs of "hitting" as you put it wont mean much at 6k+ RPM's. PTV contact could bend a pushrod in the best case,or bend a valve and you get to do this all over again or maybe much worse.

[SSdimension]

Originally Posted by JFM-jr

Well I can tell you if the head gasket thickness was causing PTV contact then you dont have enough PTV clearance in the first place no matter what gasket you use. Secondly turning a motor over by hand without any signs of "hitting" as you put it wont mean much at 6k+ RPM's. PTV contact could bend a pushrod in the best case,or bend a valve and you get to do this all over again or maybe much worse.

Thanks for the advise. Im going to crank it anyways lol. I trust everything is right and this set up has been used before in my ex friends ss. If anything I still got my stock cam, pushrods, and heads. Thanks Antonio.

[JPH]

Originally Posted by Thimble

No, actually it's on a 111 LSA.

My X4 cleared with stock heads/gasket...but as best I can figure, with only about .040" clearance to the intake valve. I put about 2000 miles on the car when it was cam-only.

I replaced the heads a few months after I put the cam in, and there were no marks on the pistons.
The heads that went on were milled .025", have a larger 2.02" intake valves, and I used a .040" gasket.

Since all of that killed the little clearance I had, I cut .110" deep notches in the pistons for the intake valves only to achieve approx .090" p/v clearance. I found exhaust valve clearance to be fine, no notches were needed.


I would just flycut it and be done with the issue. (ina addition to double/triple checking your timing chain is on correctly). Even if you found no contact, there would be very little clearance anyways.

NO shit. The last one I had doctored was on a 113. Hmm, guess the guy ordered it wider for more ptv.

[JPH]

Originally Posted by JFM-jr

I am running this camshaft currently. 5.3 heads milled 23 thousandths and a 2.08 intake valve. Using the GM LS2 MLS gasket I flycut 60 thousandths to achieve the valve drop figures LG suggested. I have always found the tech support there excellent for stuff like this.

Damn JFM, your car is flying now! Congrats.

[JFM-jr]

Originally Posted by JPH

Damn JFM, your car is flying now! Congrats.

Thanks to help from knowledgable guys like yourself.