[Umbriel]

Originally Posted by KingLT1

LT4 titanium intake and Manley severe duty exhaust for higher power builds(800-1000whp ball park) on a budget.

Ferrea titanium with hardened tip intake and Manley extreme duty exhaust for the all out builds.

Take note I am no builder but I do pay attention to a lot of builds and watch closely to see what does and doesn't work. I would contact somebody like Brett Stewart or Ryan @ GPI and pick their brains... but my guess is they will advise something close to what I mentioned.

Thanks I appreciate it. I am running a 416 with a Huron Speed twin turbo kit and Crawford Racing port injection. Threads like this worry me a little because I am still on the stock heads.

[Choda]

Thanks King for the valve info!

I have an idea on what happened. Hard part failure. I need to finish pulling the short block out for inspection before I get ahead of myself.

[Umbriel]

Originally Posted by Choda

Thanks King for the valve info!

I have an idea on what happened. Hard part failure. I need to finish pulling the short block out for inspection before I get ahead of myself.

Do you think it was a valve that failed?

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[Choda]

Long time since an update but i wanted to tear into things and get a better feeling of what happened before I got ahead of my self.

First, pulling the motor with the bumper, rad, fans, cold piping was a PITA but I got it done.

Valve to Piston. Every intake valve was hitting the piston. There is a clear wear mark on every piston where the valve notch is. Reading Parrish thread this could be because of the installed height of my BTR660 springs OR high boost/back pressure. Not sure which of the two but ill be following his lead on using the .80 drop retainers in the future. One thing I'm not sure about and looking for knowledge is the VVT. We did not lock it out with this build. Could that have had issues ( oil pressure,rpm,whatever ) that would cause the PTV contact? I will be locking out the cam next build. Might do the lock out kit or the LME timing cover with single bolt cam gear since i need a new cam as it is.

Catastrophic hard part failure was a piston wrist pin failure. Either the pin came out ( unlikely with the amount of miles and abuse) or the piston broke at the pin. I see a lot of kits offer upgraded HD wristpins. The #2 piston wrist pin failed which disconnected the rod from the piston. The rod end smashed closed but never broke.

Block doesn't have a hole but has a decent amount of nicks and scrapes from pieces flying around. Rotating assembly and all pieces have damage.

Now I'm deciding on what to do.

A. Used factory LT1 and install "better" drop in kit again.
B. Used factory LT4 short block.
C. Thompson, LME, TSP forged 376 or 416.

Will option A or B hold more power? LT4 blocks are better and come with forged internals. The one I found is a fresh rebuild from a highly known and recommended shop with main bearing clearance issue addressed. Are the drop in piston and rod combos better than the factory forged in the lt4?

If Option C - which of the three companies would you use and why? LME is the most expensive, not sure how the same engine from TSP is 1k cheaper. TSP spits these engines out daily and has a good name. Thompson is the cheapest and offers a warranty.

What ever I decide to do, I need a Heads, Cam, lifters, oil pump, HG, blah blah so I'm hoping to do a package deal to try to save on cost and shipping. One and done approach.

[Umbriel]

I went with a Thompson 416 in this car but had a LME in my 4th Gen that went 8.8 @ 156 mph and held thr power with no issues.

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[ZO6Ted]

A 416 isn't but 1k more that a 6.2 and don't forget the LT5 long block that is available. SDPC or Pace. Another option...

[laynlo15]

I just sold, crank, block and pistons to a guy in Texas.

[parish8]

i think your tune looks fine.

not sure why your intake valves were hitting the pistons but that seems like the likely initial problem. i was floating the valves at something like 6600rpm before i shimmed the springs properly. after i was able to rev to 7000rpm cleanly.

i also broke a valve but it was a hollow stem exhaust valve. it was a 100deg day and i didnt give the car much time between runs. i kinda feel like i was asking for it but it.

for motor options i got it down to 2 choices.

an iron 6.6 from kurt urban. stock iron block, stock center counter weight forged crank, stock lt4 heads, high end pistons and rods and all the other stuff to go with it. came out to about $13k

or a junk yard gen v 5.3. reuse some of your old stuff like the studs and maybe cam. add in some drop ins, good springs, lifters, pushrods... then hit it with some real boost. total cost of about $4k.

i am going the 5.3 route for now. sounds like fun. just got some parts so i will be starting it soon. i am going to go to the track a few more times with the 100% stock 5.3 in the car and see if i can get a 6.50 out of it.

[Choda]

Thompson is looking better and better as far as a 416. They also sell forged 5.3s. ehhh I dont know.

Parrish I saw your 5.3 pics. it crossed my mind. It’s about half the cost and I’m betting still make the power for 9s.

[ZO6Ted]

[QUOTE=laynlo15;10882738]I just sold, crank, block and pistons to a guy in Texas.[/QUOTE
To an old worn out goat in Tx with visions of grandeur lol. Excellent transaction my friend you went above and beyond. Still waiting on machine shop to do their thing.

Choda, speaking of 5.3's...I'm leaving this for you sir. Could've bought this in stead of my build. Think I screwed up. https://www.performancetrucks.net/fo...-141-a-556777/

[gtfoxy]

Originally Posted by parish8

i think your tune looks fine.

not sure why your intake valves were hitting the pistons but that seems like the likely initial problem. i was floating the valves at something like 6600rpm before i shimmed the springs properly. after i was able to rev to 7000rpm cleanly.

i also broke a valve but it was a hollow stem exhaust valve. it was a 100deg day and i didnt give the car much time between runs. i kinda feel like i was asking for it but it.

for motor options i got it down to 2 choices.

an iron 6.6 from kurt urban. stock iron block, stock center counter weight forged crank, stock lt4 heads, high end pistons and rods and all the other stuff to go with it. came out to about $13k

or a junk yard gen v 5.3. reuse some of your old stuff like the studs and maybe cam. add in some drop ins, good springs, lifters, pushrods... then hit it with some real boost. total cost of about $4k.

i am going the 5.3 route for now. sounds like fun. just got some parts so i will be starting it soon. i am going to go to the track a few more times with the 100% stock 5.3 in the car and see if i can get a 6.50 out of it.

I think I remember some chatter over on LS1tech about getting LT heads to work on a LS.

Then there’s what’s his name with the 4.8 GTO that swears by the turbo 4.8 combo.

Anywho, the crank will last a while. If you’re running a hydraulic cam & quite rich, change the oil often.

[gtfoxy]

Originally Posted by Choda

Thompson is looking better and better.

Parrish i saw you’re 5.3 pics. it crossed my mind. It’s about half the cost and I’m betting still make the power for 9s.

Woh!

[Umbriel]

Originally Posted by gtfoxy

I think I remember some chatter over on LS1tech about getting LT heads to work on a LS.

Then there’s what’s his name with the 4.8 GTO that swears by the turbo 4.8 combo.

Anywho, the crank will last a while. If you’re running a hydraulic cam & quite rich, change the oil often.

I change the oil on my turbo LS/LT every 1500 miles.

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[Choda]

Originally Posted by gtfoxy

I think I remember some chatter over on LS1tech about getting LT heads to work on a LS.

Then there’s what’s his name with the 4.8 GTO that swears by the turbo 4.8 combo.

Anywho, the crank will last a while. If you’re running a hydraulic cam & quite rich, change the oil often.

We are talking about LT 5.3 not LS.

I also change my oil at 50% in the dash info. oils cheap compared to turbos and engines.