mulletwearingtadrive

iTrader: (10)

i was recently told this by a mustang guy.............

how long do stock, bolt on LT1s typically last under boost......?

Alex94TAGT

That must have been some good stuff.


In all honesty, that question is a little too vague to answer. Too many variables. How much boost? Intercooled? How much mileage? How hard will it be driven? Good dyno tune, or something cheap and generic?

Generally speaking, no, a high-compression motor using hypereutectic pistons is exactly what you DONT want for a good blower buildup. That's not a good combination for anything other than really low-boost levels. Otherwise, it's a ticking time bomb. Could be a month getting thrashed around with 9psi, or it could be two years driving like a granny with 4-6psi. The ring lands generally don't hold up, from what I've read.


I wouldn't even consider a blower without building up the bottom end. Which, is exactly what I'm doing...

Crazyz28

Depends on how many miles on it, how much boost, how you drive it, and the condition of everything else. Prepare for a rebuild if you put a blower on a stock engine. BTW, the high compression of an lt1 does not like boost, and the pistons don't like to hold their own either.

Ryan

buffman

iTrader: (9)

well I at least know the stock LT1 will take it for some time from Keith Mease's expirements. Stock Long block w/ over 250+ on it just new gaskets (rotating assembly untouched), and a close to stock reground cam. Stock Iron heads that were cleaned up w/ new valve stem seals and springs. Twin Screw Roots Blower off the lightning (Eaton M112?). He had well over 5,000 miles on the setup running 8-10 psi (non intercooled) and besides the fact it had serious blowby from the high mileage, it ran just fine. I would still suggest what's already commented. Build a motor meant for boost

Saad06

iTrader: (1)

i onno man..them damn LT1 blocks can hold their own pretty damn good... but yeah... forged internals is recommended for high boost.. thats what im going to do if i get bored/rich

My2kz28

iTrader: (1)

Hes right in this regard. Lt1 iron block hold boost just fine, its the ring glads that can go over time. It also depends on altitude as well. Someone running 9 intercooled psi here at sea level in CA, may have problems down the road as opposed to someone in high elevation where atmospheric pressure is less may not have any problems.

TwoFast4Lv

iTrader: (8)

As long as you stay under 8Psi and do not drive them hard they will last.

You get much over that and the pistons give up....thats How I lost my first motor

My2kz28

iTrader: (1)

I had a buddy that had his lt1 blow under boost. He had a p00b ati, 2 core intercooler, he ran the fmu and inline booster. Well the thing is that he ran the kit untuned on 8 psi using the FMU and his lasted 25k. He doesnt drive it hard all the time, but when he does, he drives like a crazy ***. There are many variables to consider when accusing the lt1's ability to handle boost, as that depends on the driver and the setup. A moderate tune with ignition retard and a F/A ratio around 12:1 is fine on most blown lt1's ive seen come through here. Problems arise when blow by happens on high mileage engines. The reason people (for the most part) think that lt1's dont last is that you only hear the horror stories, you rarely ever hear people talk about how good their car runs on it, because it is not as interesting as hearing "OMG, i blew my engine!" Most of the horror stories i have seen are the people who dont get a proper tune or insufficient fuel pump or injectors, and take the car around the block for a "spin" hammer the throttle, run it lean and blow **** up. For the most part, lt1's arent ideal boost engines, but with the right setup, they run just fine. If your smart with the setup (6-8 psi INTERCOOLED, proper "dyno" tuning, and a supporting fuel system) guys get decent life out of the lt1.

NXSLT1

You have to watch detonation, as with any SBC. That means backing off on timing and possibly running race fuel if yer running alot of boost on the stock compression ratio. Compressed air heats up so if you have a non intercooled setup detonation will be even worse.

'68LT1camaro

iTrader: (1)

I haven't read the entire thread, so I'm not sure if this has been stated yet, but TYPICALLY, stock LT1's last for around 15,000 miles with boost. Obviously, this is not an exact number. This is just an average. It could vary greatly, but what this should tell you is that once you slap that blower on, your motor becomes a ticking time bomb. It you want a supercharger, and the power that goes along with it, your gonna have to pay a price for it. When it comes to boost, you'll need to build the engine for it. At a minimun this means lower static compression through the use of a forged dished piston, piston rings that are gapped properly for forced induction, bigger injectors and fuel pump, and a GOOD tune.

Raymond

My2kz28

iTrader: (1)

So pretty much the same exact thing that I stated above?

BizZzatch350

iTrader: (33)

LT1s love nitrous, stock form they dont have the right pistons for blowers to be happy. But then again, building up a well built LT1 isnt that expensive, its a SBC.

TwoFast4Lv

iTrader: (8)

yup I would say 15k is Normal. I had the P600B also with the 12 rib belt and 2/3 core(one large *** cooler under the car) Smallest pully for that kit was 9Psi.

Was out playing one night, 40° foggy and we are sea level. Perfect boost weather....Gauge hit 11psi and three pistons gave up there ring lands...

I will agree my fault. Then again I drive my car not show it

Then there was the time the by-pass valve stuck closed and the blower let go threw the new motor but that is an entirely different story