Im considering using the LE5 intake manifold with a 62mm throttle body, bigger injectors, and a bigger fuel rail. What type of gains can I see with that?




R.I.P. HardcoreXSunfire...And introducing HardcoreXCavalier

A really crappy running car (if it'll run at all) without a tune to compliment. I did the LE5 intake mani with LSJ injectors and a tune, and my low end stayed the same, but after about 3500-4000 there's a marked difference in pull. I have yet to track or dyno it yet though (track is next friday, dyno is whenever I can come up with $50). I have yet to get my 63mm throttle body on, but that'll also help out throughout the rpm range. One quick note: the CrateEngineDepot adapter plate for the TB will need to be bored out to accept the larger TB and you'll need to drill the hole for the IAC valve pass-through into the mani.

Btw, you don't need a bigger fuel rail at all, your stocker is more than adequate until you start pushing a TON more power, or alcohol lol.

I know there was a gain of close to 12whp on adding it to a 2.2 cobalt, there was a dyno run showing it on crate engine depots website.

just the fuel rail gives ya 20whp

I know the gains on the Cobalt were impressive, WITHOUT a tune.

I gotta get mine and set my wideband up. I'll get proof if it leans out unsafely.

im installing mine right now and i also have a wideband so once i get it on later ill tell you if it leans you out or not

Zach Reliford wrote:

I know the gains on the Cobalt were impressive, WITHOUT a tune.

I gotta get mine and set my wideband up. I'll get proof if it leans out unsafely.

the cobalt is also able to adapt better having a mass air flow sensor as well, the J's ecu cannot change the variable on a stock tune and even with injectors will run lean.

You'll need a tune. The fuel rail is wasted money IMO. There are decent gains to be had especially after the normal peak of 5500rpm.

my car leaned out after 4500 rpms over 1.0 afr

so it def. flows A LOT more air. my problem is I need bigger injectors...

yea i was at 90% idc before tuning with the mani installed...

i forget to say i will be getting a tune as well. that goes without saying. so no need for bigger injectors or a bigger fuel rail?




R.I.P. HardcoreXSunfire...And introducing HardcoreXCavalier

The fuel rail is completely unneeded, but the injectors would be a good idea. Get a set of LSJ injectors off of Cobaltss.net...they're usually around $50 sometimes less for all four.

well the fuel rail i already have is from an 02 Ecotec which i was told is better? and it cost next to nothing. but i had planned on the LSJ injectors. im thinking this could be a good idea




R.I.P. HardcoreXSunfire...And introducing HardcoreXCavalier

Qwibby {T3H Old QBE} wrote:

my car leaned out after 4500 rpms over 1.0 afr

so it def. flows A LOT more air. my problem is I need bigger injectors...

How is it up to 4500 rpm? Does it feel any better, run any better, or worse without a tune? Reason i ask is after i install mine it could be a week or so until i get a tune so i'm just curious. Thanks

SO...how bout the LE5 vs a ported stock manifold?

No, the LE5 manifold is alot higher flow, porting a stock 2.2 manifold will not have the same effect


15.0 @ 90mph with only a intake and exhaust.

Matt Burgess wrote:

Qwibby {T3H Old QBE} wrote:

my car leaned out after 4500 rpms over 1.0 afr

so it def. flows A LOT more air. my problem is I need bigger injectors...

How is it up to 4500 rpm? Does it feel any better, run any better, or worse without a tune? Reason i ask is after i install mine it could be a week or so until i get a tune so i'm just curious. Thanks

it actually runs richer because I'm not moving enough air. we had it before that at wot it was 12.5 across the board. Now its like 11.3 @ 2k-4K and then goes way lean by 7k. at 7k Im over 13

So in order to use this manifold you need larger injectors and a ECU retune?

Pretty much that's what it amounts to, Ronin.

Bummer...seemed like it might be a cool afternoon project, but thats more than I need to get into.

HardcoreXCavalier wrote:

well the fuel rail i already have is from an 02 Ecotec which i was told is better? and it cost next to nothing. but i had planned on the LSJ injectors. im thinking this could be a good idea

if ya want shoot me an email roy_boy80@yahoo.com i got a set of of the LSJ injectors, fuel rail and the lines. just laying around no need for them anymore shoot me an offer shipped for what you want



sunfire gone she will be missed very much