Need help, my 6.0 build just took a turn for the worse.
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Need help, my 6.0 build just took a turn for the worse.
Basically here's the boat I'm in. I started building a LQ9 with LS3 heads. Heads have been cut .030" and I had Pat G spec me a cam. Needless to say I've ran into a few problems with my build mainly due to not having a machine shop close by that knows these engines.
My latest set back is I had to have the stock flat top pistons fly cut. Well, the machine shop cut the pistons wrong, now I'm screwed. I would like to just buy a set of forged pistons and rods, however that's just not in my budget right now.
My only other option is that I have a LQ4 that I could put in the car. I definitely do not want to get into having to fly cut the dish pistons and with the cam I already have that would have to be done too. SO, I'm gonna have to have another cam for sure. I can swing buying another cam, but not pistons and rods.
I have the LS3 heads and have the stock 317 heads that are on the LQ4, I have carburated intakes for both style heads. What do you guys think my best option is, I really need to get this car going to run points. It's a track only foxbody mustang with a TH350, 8" PTC converter, 4.10 gears, and 950cfm carb.
Thanks for any help.
My latest set back is I had to have the stock flat top pistons fly cut. Well, the machine shop cut the pistons wrong, now I'm screwed. I would like to just buy a set of forged pistons and rods, however that's just not in my budget right now.
My only other option is that I have a LQ4 that I could put in the car. I definitely do not want to get into having to fly cut the dish pistons and with the cam I already have that would have to be done too. SO, I'm gonna have to have another cam for sure. I can swing buying another cam, but not pistons and rods.
I have the LS3 heads and have the stock 317 heads that are on the LQ4, I have carburated intakes for both style heads. What do you guys think my best option is, I really need to get this car going to run points. It's a track only foxbody mustang with a TH350, 8" PTC converter, 4.10 gears, and 950cfm carb.
Thanks for any help.
#4
Run the lq4 with the 317s and buy an off the shelf cam for now. Like a tsunami cam or trex. Think you can even shave the heads .030 and have no ptv issues. Save the custom cam and ls3 heads for the built motor when you have the funds to get it together. jmo
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Shop said they'd cut .075" on the intake side and .050" on the exhaust to get me a hair more than the .080" intake and .100" exhaust minimum I've read I needed for my build.
BUT, they apparently cut the depths backwards. As now I have .060" intake and they must have cut .100" on the exhaust cause I have .160" on the exhaust.
I may can get them to cut an additional .020" out of the intake side, cut I'm worried the exhaust side may be too much.
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I dont think you would have a problem running the pistons as is with .060 clearance. Most people have found that you can run the LS motors a little tighter piston to valve. I would run it. Whats everyone elses thoughts on this? Eric L
#10
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I'd just get the intake sides re-done.
As long as the piston top thickness isn't compromised... A little extra clearance isn't going to hurt a thing.
As long as the piston top thickness isn't compromised... A little extra clearance isn't going to hurt a thing.
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Another option, if you're interested, are the new Pro-Tru pistons from Wiseco. They are designed to work with stock rods (bushed rods; not the older press fit rods, but I'm 95% sure LQ9s had bushed rods ). They have a +4cc dome and valve pockets that will work with both LS3 or cathedral port heads. Best thing is.....they come with wrist pins and rings and are pretty cheap for forged pistons. Here's a link: http://www.texas-speed.com/p-771-wis...22-stroke.aspx
These are what I plan to eventually slip into my LY6.
#20
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Eh.
I know the stock lq9 replacement pistons with rings are less than 400$ shipped new.
If there is gonna be no spray involved,they should be fine.
And they will replace the stock slug. As is. No balancing necessary.
If everything is ok. Prolly just gotta file to your needed ring gap.
I ordered some hbeam rods with arp 2000 series rod bolts, forged pistons,rings,wrist pins,locks. For 1100$ shipped. Need to rebalance anyway. So just went for forged stuff.
4.085 bore 6.125 rod set. 3.622 stroke
Boring gen 4 ly6 6.0 .080over
380ci(379.73actual)
I know the stock lq9 replacement pistons with rings are less than 400$ shipped new.
If there is gonna be no spray involved,they should be fine.
And they will replace the stock slug. As is. No balancing necessary.
If everything is ok. Prolly just gotta file to your needed ring gap.
I ordered some hbeam rods with arp 2000 series rod bolts, forged pistons,rings,wrist pins,locks. For 1100$ shipped. Need to rebalance anyway. So just went for forged stuff.
4.085 bore 6.125 rod set. 3.622 stroke
Boring gen 4 ly6 6.0 .080over
380ci(379.73actual)
Last edited by NemeSS; 04-15-2012 at 01:36 PM.