newschool72

iTrader: (12)

Guys, I am about to drop the coin on the GM dual-plane L92 intake unless someone has seen some dyno tests to prove i shouldnt. Talk to me people as I need the input.
My combo is -3300lbs 72 camaro
LS3 (376 cid)
Comp LSR269 (219-235 at .050/ 607-621 lift) 113LSA
10.7 comp
stock heads
1 7/8ths longtubes
Fast EZ EFI
Vic jr L92 intake(for now)
2004r trans w 2200rpm lock-up convertor
8.5 in 10 bolt w 3.42 gears
25.7" tire

If I can get a sizable increase in torque without loosing much HP at the top, along with better drivablity(not bad at all now) I want to change. I know we have gone through this all before, but alot of time has passed and I was hoping someone would have a real answer to the question. Oh and my vic jr will be for sale, if the swap is made.

speedtigger

iTrader: (16)

I have never seen anyone do head to head testing on that intake. I am looking forward to seeing your results.

newschool72

iTrader: (12)

Hey tigg, it wont be much of a test because I havent really tested the vic jr. I am down after a neck surgery for another 5-6 weeks and just want to gather parts to optimize my combo. A speed shop in N Ga. posted a side by side comparo, but the engine was only 330ish cid. the dual plane beat the single plane in HP and TQ at every rpm, but by only 10-15 #s on tq and 4-8#s on HP.I was hoping to see something with a few more cids tested.

topbrent

iTrader: (1)

I think the single biggest problem with that GMPP Dual Plane intake is the price.

Due to the Rectangle port design, it looks like it has plenty of internal volume to support breathing at higher RPM and by nature of being a hi-rise dual plane, it will have great low speed/mid-range manners.

D&A was going to do a back to back test between the GMPP Single and dual plane on their 409" motor, but I haven't heard of anything yet.

It would be interesting to see where the single plane passes it on the graph.
My guess is that the Dual Plane would be more fun to drive everyday.

newschool72

iTrader: (12)

Yea , D&A posted the test on the 334 engine and the dual plane won out right at all rpms. Sure would like to see the bigger engine test.

topbrent

iTrader: (1)

Their 409" engine sure didn't suffer from that dual plane intake. Small cam, tight LSA and ridiculously huge torque production from that thing. It holds on over 500ft/lbs forever and would be a seriously fun motor to drive.

224°/228° 108°+6°

IMHO, For the same reasons the early timing events bolstered low-speed and midrange power production, they were also probably more of a key in limiting extended 6500+RPM HP production rather than intake selection.

For as small as that cam is for the displacement(409"), a single plane intake might not have had that much of a different impact on HP above 4000rpm and probably would have just resulted in less average HP/TQ than the dual plane in this scenario. Remeber, this engine was designed to run between 2500-6500 in the EMC challenge.

http://www.popularhotrodding.com/tec...s/viewall.html

On the Dyno 409ci LQ4 Chevy

RPM TQ HP
2,500 533 257
2,600 534 264
2,700 549 282
2,800 562 300
2,900 570 315
3,000 575 329
3,100 579 342
3,200 581 354
3,300 580 364
3,400 577 374
3,500 578 385
3,600 579 397
3,700 577 406
3,800 572 414
3,900 569 422
4,000 568 432
4,100 566 442
4,200 564 451
4,300 565 463
4,400 567 475
4,500 565 484
4,600 565 494
4,700 566 507
4,800 570 521
4,900 569 531
5,000 565 538
5,100 564 547
5,200 563 558
5,300 559 564
5,400 553 568
5,500 549 575
5,600 545 582
5,700 540 586
5,800 532 588
5,900 520 584
6,000 507 579
6,100 491 571
6,200 479 565
6,300 470 564
6,400 463 564

newschool72

iTrader: (12)

That engine rocked for such a mild cam! On my engine , I know the dual plane would be better suited to the 113LSA on my cam, but the thing runs like a scalded dog with the Vic jr. And the FAST EZ EFI self tunes so well that it runs seamlessly . I guess I want someone to tell me I will pick-up major torque down low and not give up much upper HP. To be honest, I cant use the torque I have now.It blows the tires off anytime I lay into it in first or second gear.
If I was running a carb I think it would be an easier choice to make, but with the EZs tuning ability, it covers up any problems my mis- match might have. I guess that is a good thing , but it takes all the fun out of tinkering with the car.

ZONES89RS

iTrader: (25)

With a 2200 converter, and street driven majority, dual plane all day.

speedtigger

iTrader: (16)

Damn. 102 ICL. That is some serious advance. That explains why it peaked before 6,000.

newschool72

iTrader: (12)

Agreed"on paper", but it does really well with the single plane, to the point that I wonder if I could tell the difference on the "butt dyno". The only place it feels a little flat is in high gear with convertor locked up at 2000 rpms, But doesnt everything, except a diesel ?
I think that 102LSA is the reason that 409 made peak torque at 3200rpms. The dyno run looks more like a mild big block than an LS. I wonder if a profile like that would be streetable IE... plenty of vacuum for power brakes and not shake my vintage air apart ?

ZONES89RS

iTrader: (25)

It is to the point that anything 90% street if better off with the dual plane these days with these engines. Also to know if a single is better is absolutely knowing the engine will have stall speed above the low end where the dual thrives, but that is all common sense these days.

As for the brakes, good question, I have not had any issues with these newer engines yet.