Opinions on LS2 vs LSX
 

What would make more power, LS2 intake with GM 90mm TB or LSX intake with GM 90mm TB. The car has VaraRam, stock p&p 75mm TB, LS6 intake, Kooks headers hiflow cats & xpipe, Corsa Indy's, AFR 205's, 224/228 .581"/.588" on 112lsa @ +2, UD pulley, 4:10's, SPEC Stage 3 w/al FW. Just made 413rwhp, 396rwtq. I'm hoping for 20 more than what I have now. Am I dreaming?

I don't think you'll get 20 rwhp either way. I'd expect 10 +/- 3 or 4.

I went LS2 for two reasons: cost and quality. Cost: $400-ish vs $800-ish (when you include fuel rails in the cost of the LS2). No brainer there. Quality: I've heard far too many stories about the LSX intake leaking air because of the 3-piece design. Granted, the ports on my LS2 were pretty rough, but an hour with a die grinder and they're now in good shape. The LSX needs the same treatment though. Since the LS2 is glued from the factory, it shouldn't leak.

I'm hoping to do a dyno between the LS6 & LS2, whenever I get all the parts I need (thinking about getting an 85mm MAF, and will need the boots to go from MAF to TB and lid to MAF).

Just an aside-
Those sound like low numbers with that setup- you should be able to get 40+whp from tuning alone according to the other AFR #'s that I've seen.

Ben

Thanks Ben. I have had it tuned. running flat 13.0:1 AFR from 2k to 6.8K. Timing is at 28 degrees. Those numbers are in line with the cam I am using. I am thinking of pulling the heads and milling another .020", they are milled .010" now and I'll still have .090" intake valve clearance. The other thing I am planning to do is redegree the cam to 109ICL. Some numbers I have been running say I should pick up around 12-14hp with those 2 items. Also I am running 4:10's, and my rear wheels wheigh 63lbs. ea. I was hoping for higher numbers but am not dissatisfied. This cam drives sweet though.

Expect to lose another 5 rwhp if you advance the cam 2 additional degrees. You will make at least 5 rwhp more if you retard it to 112 ICL. You want your intake closing point between 44-46 degrees ABDC. Closing it earlier will kill power.

The LS2 dosen't move any more air than the LS-6. The gains that are seen are from the larger throttle body, not the intake. The LSX moves more air due to a better runner design and the larger TB, so if you are going for all out power and money isn't of the highest concern, I'd use the LSx.

Got any flow tests to back that up? If it didnt flow more....they wouldnt have gone to the bigger intake. They would have "revised" the ls6 TB area to accept the larger TB. That would have been alot cheaper than making a whole new intake.

Patrick, I assume you are stating 44-46 degrees at .050" not .006? You are correct. The calculator I am using shows me 2 different graphs. 1 for .050" and one for .006". For the .006" events 109 ICL makes the best all around power and for the .050" events the 112 ICL makes the best power. :confused:

No, I particularly don't have any sheets, but that is what our wonderful sponsers over here are for. At least one of the very trusted ones posted this info a while back. He flowed both intakes and there were no noticable diffrences between the 2 flow wise. Just passing along the info.

This is what Futral Motorsports found in their testing of the LS2 vs LS6:


Heres the skinny...on the flow bench the LS2 dosen't "flow" any more air over an LS6 on a single runner test,but on a dyno test average gains have been 12-16 HP over an LS6 on a good heads\cam 346. The HP gain is due to a little difference in plenum design and the 90mm T\B setup. They are a 3 piece design and use the same 4-bolt flange layout as a FAST\TPIS 90mm so they will bolt right up. So I feel that they will be a good mod for the money spent. https://ls1tech.com/forums/images/sm...gr_stretch.gif

Here's what Kurt@W2W came up with:

On a 346 road race engine with a ZO6 manifold the flywheel HP went from 523 peak to 540 peak with the manifold and 90mm TB. The early gains are not there on the one I tested, the gains were mostly above 4500 rpm. It looked to me like the 90mm TB was responsible for most of the gain.

The manifold will fit anywhere a LS6 will, although the newer breather coming out of the valley cover may need some modification.

Kurt

Has anyone flowed the runners on the LSx vs LS6 on the same bench?

Thanks for the quotes. Those are the ones I was refering to.

That's what I assumed. That's why I brought them into this thread so others are on the same page. No pun intended.

The LS2 setup seems to be a waste of money if you already have an LS6. A few horses at the wheels isn't worth it. If you're gonna upgrade, do it right and spend the bucks for a LSX. Of course, if you have an LS1 intake then it's a steal.

I sent my Fast 90mm TB back. It was a complete peice of garbage n did not weigh enough to use as a boat anchor. My TPIS 90mm will be here tomorrow.

I have installed an LSX 90mm on another car and had to use silicone around the MAP sensor port so that it would seal. The TB for that car had to be sent back to FAST to be worked on.

Paid 235 for an LS2 intake, 139 for the fuel rail, and 18 for injector orings. Already had the wire to extend the MAP sensor plug.

I sold My LS6 intake for more than I paid for the LS2 :angel:

Spent about an Hour cleaning up the ports with a Dremel.

The ONLY advantage to the LSX is that it is easily disassembled so that it can be ported.
I will have track times next week weather permitting.

Brad

If you don't mind me asking, What did the TPIS 90 mm cost you?

There $500 + your stock TB in return last time I checked.

5 bucks more than the FAST cost me. Sorry I can't post the price on here.
Talk to KJ @ SDPC for a good deal.

I just put it on and it is 100% better than the FAST. It even came with the bolts for the TPS n IAC.

Brad

:secret2: I was told by a very reliable source that there will be a billet 90mm TB being offered for less than $350 and no core charge in a month or so :secret2:

SWEET!!!

:lurk: