Good luck with the build. That thing is really gunna rip with that GTS. My 6.0 with the stock tty's did the same thing. I think they fatuge after awhile. Be sure to surface the heads, and make sure all the 8 pistons are comming to the top.

 

i came across the rx7 dude on ls1tech. very impressive on a stock bottom end. ive thought of studding my motor before i run into any problems. is it alright to intall studs one by one without removing the heads?

 

Nice truck! That thing rips!

Starting a single turbo 4.8/4l80 build on a Chevelle soon myself. There is not really much info on 4.8 builds over there so I thought I would try here. Seems that I came to the right place.

What's the plan for the MP70 you took off? That is what I was going to run on the Chevelle.

 

Hey, what casting number of heads are those??? 5.3's and 4.8's are known to have bad castings that crack and let out coolant. Mine was leaking into the crankcase. I just changed a set of 706's off my 5.3 for a set of 243's. Just dont want you to go thru all that work and still have a leak. Goodluck!

 

Well I just got back in town last night from work. Came home to a UPS box from Texas Speed.. Hope to have it running by sunday for sure. Also my heads are Cast # 862's. Can any one tell me if these have any "Known" problems?" Any key areas to inspect?

Head: 1999+ 4.8L / 5.3 Liter Truck
Material: Aluminimum

Quick search : Combustion Chamber Volume: 61.15cc
Compression Ratio: 9.5:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

 

After doing a little more research, I do NOT have Castech heads, so I should be good to go, also didn't notice any hairline cracks around the stud mounting surface.

I've read around the GM forums the answer is no. I will say however I've done this on many 4g63T engines (turbo eclipse/talon) and ran over 35PSI with no problems. I really don't understand why there would be a difference. If I would have know more about LS engines having a 3 MLS head gasket stock I would have tried to do the 1-1 swap from day one. The stock bolts look very weak and i'm surprised they held as long as they did, i'm sure the MLS gasket had a LOT to do with it.

 

didnt think it would be okay to do that but thanks for clearing it up for me. i guess ill wait until when/if something happens and need the heads off

 

Can u give me a link to where u got ls9 gaskets at?

 

Pm sent Bluchevypick...

 

Update... she lives once again! I will say this is a pretty damn good job for a one man operation! So far it seems to have sealed up great. Drove it for a couple days then today started doing some tuning pulls for this weekend trip to the track.

Some info on my night of tuning, I took 1 degree timing away from the MP70 tune at 15psi that went 7.00@98. I started doing second gear tuning pulls at 10psi,then 11, 12, 13,14,15. 15PSi on the PTE 76GTS is...well..best way to describe it....Violent!! l. I turned it back down to 13.5/14psi and made a 1st-3rd gear pull, feels very strong, running around 15.5 degree's timing and 11.5 air fuels. After all the tuning, coolant was on the same line I left the house at. (score!)

I'll see how she does Saturday, hope to get a NPB. Worked hard on those damn studs and gaskets, time to play!!

Couple shots of going back together.