I have heard many stories of how people end up blowing their engines with the ATI 8# s/c as even with the tuning something tends to go wrong.

Many people say the LS1s wont be able to handle so much load beause of them having hyperpeutic (sp?) pistons swung at high compression rates.

What would I need to upgrade/modify to make the 8# of boost on a ATI D-1SC Supercharger "RELIABLE" on my LS1?

If I were to replace the pistons with forged ones would that solve all my problems? I want to be able to drive my car for 6 years without it blowing up. I know the rear will have to be replaced with a 12 bolt, but as far as the engine does anything else need to be changed?

For example, would the crankshaft twist or break? What about everything else? valves, pushrods, lower engine (any and everything you can think of) ?...

If you have any input on this please let me know. I am still new to all this.

Any feed back is greatly appreciated.

 

No responses?!?!?!

 

I have alot of customers running 8-9# of boost on a stock motor and they haven't had any problems but then there are some people that have. Anytime you add this amount of boost something can happen and it also depends on how the car is driven. Some people have an addiction that makes them put the pedal to the floor away from every stoplight. Chances of something happening are greater if the car is drive hard all of the time.

The two things that I see go are head gaskets and the LS1 is known for bending pushrods at high RPMs. Lowing the compression a little would allow you to safely run more boost. *# is usually pretty safe though. If the car has been modifed (headers/catback) you'll see a little less boost on the gauge.

Hope this helps,
Tom

 

If you get a good DYNO Tune, and get forged pistions with a little lower compression (9.0) you should be good. Also a good BTM will also add extra insurance. BUt I can not express how much a good dyno tune will do for the longevity of the motor. Without it you really can not see the car's different conditions and loads and calibrate it to real world conditions. Is the dyno real world? NO, but its pretty much the best you can do in a enviornment where you have the ablity to see and change aspects of your cars tuning. In many cases I would say that a proper dyno tune is the best money that can be spent on a forced induction car. Also the tune must be done as soon as the blower is put on. Many people hold off and wait and that is when the damage is done. Good luck.

 

The LS1 and LT1 are two very different engines.


There are many many people running the exact same setup very reliably on the stock longblock. Put a good tune in it and you should be good for a very long time.

 

Pedal to the floor ... my a$$... ... that's too hard on tires, one must learn to properly modulate throttle pressures so as to elicit the "driving on ball bearings" feel, this will leave a great long streak of fresh rubber and perhaps some audible squeaking of the tires ... gonna haf to lube those tires ...

I was just kidding ... T Byrne runs a good shop and will give you good unbiased advice ... he's been supplying lots of the go fast stuff for the F-body cars for some time ... good prices and never any complaints. Highly recommended.

But like he says, 8 - 9 psi of boost is near the edge ....

And, what ATMINF said about a dyno tune ... $300 for a dyno tune, or ... $3,000 for a new engine and then $300 for a dyno tune ... you do the math ...

LS1 edit should be considered, I've used the LT1 editor quite successfully now for 3 years and it does what you need it to do. The LS1 editor has the same fields and programming capabilities from what I've seen.

Have a look at my web page, it's a step by step of how I did it and it was done with the not inconsiderable help and advice obtained from this message board. You may also benefit.

Do some searches and then come back and ask more detailed questions ... but be advised ... this Super Charging thing ... it may cost you some $$$

It can be done with a good degree of safety and reliability, you just have to do a little homework and not get too greedy.


Hope this helps

LWM

 

Very nice response. Very well put. Thank you all for the advice.

I just bought a book called Supercharged by Corky Bell. Its an awesome book that explain a lot about supercharging (as I am still new to this subject). I read 2 chapters so far (out of 20.. I think).

heres some quick questions.

1) I take it the lower the compression ratio the more boost the motor could handle with reliability? Is this true?

2) Whats a good way to reduce compression ratio to make my car more reliable? I dont want to do something like a 383 stroker as that is too much money. If I were to change to forged pistons would my compression ratio drop and make it reliable? what if I were to port and polish my stock heads and use forced pistons with an FI cam? I am not the type of person who would want to push the car to its limits. Example: if the stock motor handles 8psi I'd go with 7psi just to be safe. Now would forged pistons ONLY be fine for 10PSI (so I can be safe for 8psi)? I dont want my crankshaft to twist or break. Same thing with pushrods and everything else in the motor that you can think of.

3) A lot of people say if I were to put headers with my existing setup (slp y-pipe and corsa exhaust) I would see less amount of boost. Does this mean if I were to see 8psi on stock motor and then apply headers to it the pounds of boost would drop BECAUSE the engine would be more reliable? A little confused about the boost droppage with the headers. Dont know if the headers would be a good investment to increase engine longetivity?

 

ttt

 

Seeing as the supercharger is fixed to the crankshaft if can only spin as fast as the engine can. Boost pressure is a measure of the amount of restriction in the engine. If you make the engine more efficient at moving air, and turn the blower at the exact same speed as before the engine was made more efficient, there will now be less of a restiction in the engine and the boost will drop. You will be making more power, but the pressure will be lower. Superchargers are unable to self compensate for pressure losses like a turbo can, but If you do a bunch of mods (heads cam headers) and you drop a few PSI, you can always change pullies to up the boost back to where it was or higher if you desire.

Bill

 

Hey Bill thanks for the response. I get most out of what you said but im still kinda confused on the 3 questions I have asked.

Can someone give it another shot at explaining those questions?

please base your answers on reliability.. I do understand about efficiency just dont know how each of those questions are related to reliability.

I appreciate all the responses including you Bill. Thank you. :Cheers:

 

When you speak of reliability on a FI motor, you get reliability by keeping it out of detonation. Lower compression will allow you to run more boost with a lower chance of detonation. Alot of guys run 8 Psi on the stock engine, If you lowered the compression to 8.5-9.0:1 and kept this same 8 psi, your motor would probably live a long happy life. I don't feel that the headers would do anything for longivity of the motor, but it sure wouldn't hurt to get the most power out of the car.

Bill

 

You should figure out what your goals are. If 500rwhp is enough to keep you happy, there is no need to go internal into the engine, which will save you quite a bit. Forced Induction can get expensive quick.