But that makes more sense to me.

You know GM basically ripped off the LT1 intake from an aftermerket design, I beleive it was TPIS set up.

94NDTA;171046 wrote:
I'm going by what I know on V8 cars. V8's with higher intakes make more power up top, shorter intakes make more power in lower RPM ranges.

By the way, off topic, Did you just get glasses recently?

mmmmmm i think you have this backwards, well compare the L98 tpi setup and the LT1. The tpi runners are exactly 17" long and thus the ability for the tpi to make a shit load of TQ in the lower rpm and less power @ higher rpm's. the LT1 makes more power up top because of the shotter runners thats why you see many people with the L98 switching to the mini ram (by TPIS runner length is about 3") or the stealth ram (by Holley) the super ram is also good but i dont like it. so all in all longr runners= monster TQ @ lower rpm's and less power up top and Shotter runners= less TQ @ lower rpm's and more HP up top.
The shorter the runner the higher the peak RPM, the higher the peak RPM, the higher the HP number. This is why the tpis mini ram, holley stealth ram and the LT1 intakes make so much more power than the TPI.

**From Chevy High Performance Mag

[I][I]If you’re looking for a bit more horsepower, you could also step up to the John Lingenfelter–designed ACCEL SuperRam intake. The SuperRam runners are shorter than the TPI runners to increase top-end horsepower while sacrificing little power below peak torque. We’ve had excellent results with this manifold, and on a 420ci small-block, we’ve made as much as 525 hp and 540 lb-ft of torque with this intake.*[/I][/I]

By the way, off topic, Did you just get glasses recently?

GarageAlchemist;170940 wrote:
I believe shorter runners would make more power up top, and longer down low?

94NDTA;170942 wrote:
No.

Actually YES. Short runners = better high RPM power. Long runners = better low RPM power and more torque.

94NDTA;170947 wrote:
Explain. Like they had one butterfly valve open at lower rpms, and another on a different length runner tha would open at higher RPM?

It's simple, there's essentially 8 different intake runners. Normally the air passes through the long runners. Butterfly opens at a certain RPM to pass the air through the short runners, instead of the long ones.

thrash;170992 wrote:
I wish there were some engineering drawings showing how this system worked. The variable length intake runner stuff isn't new.. although i can't think of an application off hand.

Here's a link to Yamaha's website to give you a good idea. Move your cursor to the one thats' closest to the Yamaha symbol on the gas tank. http://www.yamaha-motor.com/sport/products/modelinnovation/6/0/innovation.aspx

The continuously variable valve lift and cam phasing are interesting and a definite departure from how VTEC used to work. Note that AVTEC is not the first introduction of continuously variable valve lift into a production engine... Valvetronic from BMW has been doing this since 2002 or so, and I wouldn't be surprised if they weren't the first.

I've heard that F1 engines use pneumatic valve trains.. i wonder if/when we'll see that in production cars. If anyone has links to drawings of how these systems work, that'd be fantastic.

integra_gsr98;170971 wrote:
The GSR had secondary butterflies stock as well.

werd^^^...stock it's kinda like listening to two "mini-vtecs" so to speak...mmmbaaaaDAAAAA...that isnt meant to be sarcastic rice like I normally would...Thats what it actually sounds like.

94NDTA;170947 wrote:
Explain. Like they had one butterfly valve open at lower rpms, and another on a different length runner tha would open at higher RPM?

Yes sir. There is an H22 sitting here with that same system. JDM 4G63's had them as well.

PSiedTSi;170945 wrote:
The idea has been used before, but obviously not as technically advanced. There are a few cars that came with butterfly valves that used different runners at different RPMs etc.

KA's had them, well at least mine did.

94NDTA;170895 wrote:
That is amazing. The idea of a variable length intake manfold is very smart. Shorter in the low RPM's for more TQ, higher in the upper RPM's for more hp. I hope this catches on with other car maakers.

There is a video somewhere that is pretty cool.

I believe shorter runners would make more power up top, and longer down low?