So why are you so against using the 60's if you have them?

 

Probably because running injectors that big is a band aid for running that much boost (15+ PSI) for so "few" WHP (330-) in an unefficient way (talking about the crappy Volumetric Efficiency).

 

lol what

42lbers are maxed on a 2.8 pulley on a stock head. Tell me again why when adding even more air u think running larger injectors that net a lower idc is a bad idea

 

42# are maxed on a 2.8 pulley on a stock head because of the "too low" differential pressure between the fuel rail and the intake manifold. Differential pressure is low because we are boosting too much PSI in the intake manifold. All caused by the crappy volumetric efficiency of the stock cams and head combo.

"I had found this following article which contain some great information, and GM Racing made some testing of a "de-stroked" Ecotec (from 2.2 to 2.0L) with upgraded head, cams ... Please read it all ! "

http://www.year2032.com/ecotec.htm

"The new turbo Ecotec immediately cranked out 350 hp at 7000 rpm on ONLY 2 psi boost ..."

"At 450 hp and 8 psi boost, the GM team began blowing head gaskets ..."

"The Ecotec was finally reliable to 650 hp at 19 psi of boost -- a relatively low level of boost, indicating outstanding volumetric efficiency ... "

How did they achieve as many horsepower with that smalls amounts of boost ? Volumetric efficiency !

Dan you previously PMed me saying that the stock LSJ head flow well. But GM states in two different publication that :

1 : Stock LSJ head is efficient (no HP loss) up to 275whp.
2 : Their own CNC midly ported LSJ head (in the LSJ Build book) is e.fficient (no HP loss) up to 320 whp.

With 19 psi of boost with a CNC ported aggressive head and big cams you should put down 550-600BHP (at least 450whp).

... and "Power quickly advanced to 350 hp ..." (350BHP since they were on a engine dyno) " ... , at which point the engine ran out of breathing room on the exhaust side.

 

You missed the part where:

The super-modified Ecotec was able to achieve a reliable 750 hp on 24 psi of boost at 9000 rpm with 10:1 compression and an unspecified fuel with extremely high octane and excellent heat of vaporization characteristics

Differential pressure can be over come by a $400 return fuel line system allowing us to further use injectors.

It also depends on your power adder. My turbo's efficiency sweet spot is in the mid 20s for boost.

XXXhp takes XXX air and XXX fuel. tolding hp constant and having the fuel to supply it u need XXX air.

You have to ways to deliver this hi pressure/low flow or lo pressure/hi flow 2 different ways to the same end verdict

There is the right way...and the cost efficient way

Both lead to the same results

 

you'd be suprised at the parts i have laying around. none of which i need right now. as of right now, my idc is lower with the 2.8 and meth than a gm stock stage 2 car. i have said it before. it all lies in the hands of the person with the lap top in how well the car is going to run in the end.

now, with the added air flow of the ported head and the cams. the car will either A. require more fuel because of the added air flow. or B. the most highly unlikely aspect of it all, not need anymore fuel.

with the added effiency of the new found air flow. boost levels will drop, but will the demand for extra fuel go up? im thinking yes, which is why im holding off on doing the 60's

 

But either way, why not just toss the 60's and tune them down? I am not sure how lofty your goals are, but you will probably need them eventually.

If you do the fuel rail option, you could probably keep the 42s a bit longer.

 

my goal still remains the same. 275 on pump gas, daily drivable. i have hit this on race gas before. hell i might be close right now, im just too lazy to go find out. this is what is keeping me from doing the 60's, the cams, the head work, because frankly. i never bought the car to get stupid with. i just wanted it to be fun and quick. which it is. this idea never did stop me from thinking about the "what if" down the road, which is why im collecting parts now.

long story short, i don't have high goals for the car, which is why i stopped at the 2.8

 

Then, keep your 2.8. 272 cams, head works, valve springs, neutral balance shafts, and an 8k rev limit should net you those numbers. You might be able to keep the 42s if thats all you want, and if not, do the return style fuel rail and you should have no problems keeping the 42s.

 

spinning the motor to 8k, i can not keep the 42's in it, because that will put me well above the 100% mark. spinning the motor to 7300 puts me over 102% as it is. i don't think with the 2.8 i would be maxing out any tables, as far as the maf and other things go. so i wouldn't run the risk of the injectors going into dump mode and just being retarded in general.

it all comes down to the basic theory of, more air, requires more fuel.

 

what about the GM performance Cams. I wanna buy those. The build book gets the SS/SC up to 300 horsepower with eagle pistons, and the stage 2.

 

stage 3 mods, full exhaust, one off cams that cost an arm and a a leg to get from comp, IF you know the right people. you have to send your cams, or blank cores into comp. and have them grind the cams. they have to be for the lsj for comp to even touch them.

 

There are no LSJ blanks from GM. Do not exist. Regrind is the only way. I think JBP offers Billet Blanks, but you need to call to get them, and of course $$$.

And GM used Diamond 10:1 pistons in the build book.

If you are already over 100% IDC at redline, that is a pretty damn good reason to toss the 60's in now.

 

the 60's are most likely going in this weekend, then will be working on the map some more to get rid of the 300 code. blah!

 

300 Code?

 

A fuel code of some sort I believe.

 

missfire code. either the fuel trims are out of wack, or it just dumps fuel at idle, or runs really lean at idle. one of the two. most likely to do with the fucked up map i have in the car right now

 

Let me know what you come up with,this 300 code has been my shadow for too long now.thanks

 

i'll get it figured out soon enough