01CamaroSSTx

iTrader: (3)

Does NRE build boosted 454 LSX's?

NO!

If you had a tall deck then maybe so.

Corona

How to build a FI 454.....it's done using a Tall Deck.


There's a young man who did this yrs before with his fire chicken ...

https://www.enginebuildermag.com/201...rbo-ls-engine/




Memory and Google search 😉
https://www.motortrend.com/features/...ntiac-formula/

01CamaroSSTx

iTrader: (3)

What he doesn't tell you is that it was with a tall deck block.

NAVYBLUE210

For ANY longevity 4.155" is the max recommended bore by many builders for FI.
This is largely for having enough gasket material between bores as well as
cylinder/block strength.

Launch

Nope not worth the risk, the head gasket seal between bores is more than likely going to end up an issue. Stay N/A or sell the block and buy another one.

Che70velle

iTrader: (6)

This. Headgasket between the cylinders is very small, which makes it weaker. I personally wouldnt hesitate to put 10lbs (ten pounds at most here) on an Iron LSX block with a 4.2 bore. The MLS headgaskets are very robust. With an aluminum block 4.2 bore you have a very thin iron liner up against a paper thin (literally) aluminum water jacket housing. With an iron block, it’s all iron, so there’s a little more strength. Is it ideal? Heck no. But for 10lbs of boost I’d try it. I’d want the best tuner in the world, AKA Darth, to ensure that there is ZERO detonation anywhere.
But indeed, 4.155 is largest recommended bore sizing for safely boosting an LS/LT engine.

Mickyinks

id try it with an oring and reciever groove setup, 1/2 inch head studs

ramairws6

iTrader: (33)

I was running 300 shot on a LSX 445 almost 10 years in a sleeved LS7 block that finally gave up the ghost. The block was done so guess what i did? Reused everything internally in a new Dart block with some Mast heads. Only major replacement was the pistons. Now i'm a little smaller cubic inch at 440 with a little room to grow in the cylinders. If you know how to build these things and use the right parts i wouldn't be afraid of boost at all.

grinder11

iTrader: (1)

I agree. Doesn't GM advertise the block is good to 2,000hp? If that's the case, I'd like GM to explain how they got to 2,000hp N/A!!!! WTF...

ramairws6

iTrader: (33)

Never happen!

grinder11

iTrader: (1)

Exactly!!

jayyyw

I wouldn't hesitate to run 10psi on E85 and with soft timing. I wouldn't run pump and meth. Maybe E85 and meth but not tuned to be meth dependent.

ramairws6

iTrader: (33)

Yup the ethanol is the key for me. Runs SO much cooler with zero detonation with a good tune. Even low trans and coolant temps is a plus.