Limits of stock LT5 with boost? - ZR-1 Net Registry Forums

A26B · 09-07-2023

Agree with Crabs.
Head Gaskets have been the first point of failure. The most resistant head gasket would be the Cometic MLS. Lingenfelter machined receiver grooves in the cylinder head, for the flame guard on the cylinder sleeve. The open deck design makes it more difficult to get everything just right. The head gasket has to separately seal oil return passages, coolant and cylinder pressure. The Lingenfelter approach functioned very well, allowing boost in excess of 15 psi (with lower compression pistons).

For a completely stock engine, I think 5 psi boost is about the maximum. The Tuning has to be spot on. 5lb boost is approx 1/3 atmosphere and that would approximate the incremental gain in power, i.e. for example, 390 hp normally aspirated would yield about 130 hp gain with 5 psi boost, equaling 520hp.

This amount of gain can likely be achieved normally aspirated, with cat-back exhaust, headers, porting, cams & tuning.

To get the really big power numbers, in excess of the biggest N/A LT5 engines, by turbocharging the LT5, will cost a lot.

Graham Behan would be the resident expert to discuss turbocharging the LT5.

Just my $0.02 also :-)

09-07-2023	#1
A26B Join Date: Dec 2003 Location: Arcadia,OK Posts: 3,374	Re: Limits of stock LT5 with boost? Agree with Crabs. Head Gaskets have been the first point of failure. The most resistant head gasket would be the Cometic MLS. Lingenfelter machined receiver grooves in the cylinder head, for the flame guard on the cylinder sleeve. The open deck design makes it more difficult to get everything just right. The head gasket has to separately seal oil return passages, coolant and cylinder pressure. The Lingenfelter approach functioned very well, allowing boost in excess of 15 psi (with lower compression pistons). For a completely stock engine, I think 5 psi boost is about the maximum. The Tuning has to be spot on. 5lb boost is approx 1/3 atmosphere and that would approximate the incremental gain in power, i.e. for example, 390 hp normally aspirated would yield about 130 hp gain with 5 psi boost, equaling 520hp. This amount of gain can likely be achieved normally aspirated, with cat-back exhaust, headers, porting, cams & tuning. To get the really big power numbers, in excess of the biggest N/A LT5 engines, by turbocharging the LT5, will cost a lot. Graham Behan would be the resident expert to discuss turbocharging the LT5. Just my $0.02 also :-) __________________ Jerry Downey JERRYS LT5 GASKETS & PARTS http://www.jerrysgaskets.com 1994 *ZR-1*, Black/Black, Lingenfelter Aerobody, 416cu in, 3.91 gears, coil-over susp, Brembo brakes, etc. 2016 Black-Red, 3LT-Z51 Auto 8-speed.