Darth_V8r

iTrader: (4)

PM me an address and I can send you a BBK. It has not been ported or anything

taman86

iTrader: (19)

ive already volunteered my ls6 and 85mm throttle body with adapter. I think it would be interesting to see if there is a flow difference between a larger throttle body and a ported stock throttle body. glad to see the testing moving forward. I might be able to have it off this weekend.

that's a bbk and ls6 so far. now we need a tpis modded ls6 which I think somebody here a few pages ago was volunteering.

FlorianGee

iTrader: (1)

I'd be very interested in the performance of the TPIS modded LS6 too!

codyvette

iTrader: (24)

That was me fellas but I was speaking of sending it for back to back dyno testing not flow bench numbers. Those are great and I appreciate the effort. I however would like specific hp gains, not calculated probably gain figures.

taman86

iTrader: (19)

flow numbers equals hp just sayin

Rise of the Phoenix

iTrader: (27)

I agree. I picked up a used FAST 90mm intake that already had the runners ported. I ported the snout out to 92mm, so in essence, I have a FAST 92mm intake. After selling the LS6, TB, and SLP Lid, I was out something around $200.00.

codyvette

iTrader: (24)

Tell that to anyone who ports heads and they will point out heads with huge intake runners volumes that fail miserably esp. In smaller (347) inch motors. I had a ported 90mm Fast that showed very shitty kpa data logs. I sold it for $200 to someone that says they can clean up and repair the **** port work.

wannafbody

iTrader: (2)

How does plenum volume affect flow through the intake? In theory, a larger plenum and/or shorter runners should support better breathing in the upper rpm range.

In one test, a BBK vs the Fast 78 was 3 hp different. Fast 102 produces about 10hp more than the 92. I can't help but think that a 102 TB loses some torque to a 85 or 90 TB.

99 Black Bird T/A

iTrader: (4)

Thank you Darth! PM sent.

99 Black Bird T/A

iTrader: (4)

Taman, thank you!

Assoon as manifolds arrive we will roll into part two.

Who else wants to help?

Darth_V8r

iTrader: (4)

Negative ghost rider! In my own personal testing (multiple iterations of this damn car lol) and some friends I talk with all the time, the fast102 GAINS torque. The main things that aid torque are mid lift port velocity and cylinder pressure.

So, what aids in port velocity? High delta pressure from plenum to cylinder, long runners to aid in gaining air momentum. So how to get high DP plenum to cylinder? A large plenum. The fast 102 is a large plenum long runner intake. There are short runner versions on the LS3, but this is the cathedral section. In fact, the fast102 runners are way longer than the BBK runners. I suspect the BBK might be a great high rpm turblowed motor intake. Like a 8000 rpm 4.8 boosted spin monster. Anywho... the fast 102 peak torque and HP RPMs match the stock intakes except in really high end builds. Why? Because the runner lengths pretty much guarantee 4800 rpm peak torque and 6300 peak HP, unless the cam timing is radical enough to change it - typically causing double and triple jump torque curves.

So, what about cylinder pressure? Well that's where the rest of the engine comes into play. And that's something else significant to bring to this discussion. This test is showing how much various intakes hold the heads back. But it doesn't mean the engine can always take advantage. So, the Dorman LS2 flows 10 cfm more than LS1, which is about 22 hp -- IF THE REST OF THE ENGINE CAN TAKE ADVANTAGE OF THIS AND ACTUALLY GETS ALL 10 CFM INTO THE CYLINDER.

it's a very important distinction because in this test we are not measuring the rest of the engine. Look at it in terms of flow list vs open heads instead of flow through the test apparatus. That's the correct way to interpret these results IMO.

And in that sense, hammer has a point. I've seen guys with stock internal LS1 and LS6 engines bolt fast 102 on and they are torquey **** engines. To the point you can see the cam is holding the engine back plain as day on the dynos. They just aren't my dynos to share. The test is actually showing which intakes choke off the motor the worst. And the least. Try to view the results this way instead of total flow. It's quite interesting.

Lastly, regarding actually losing torque and gaining hp, the only intake that actually happened for my engine is the MSD. Short runners. I had the BBK on my engine, but the cam was nine degrees off, so that data point is worthless.

/soapbox

stonebreaker

It's funny how old carburator myths have hung around for the last 30 years. Big carbs caused a loss of low end torque because at low flow the vacuum signal was weak. Fuel injection does not depend on vacuum to pull gas into the intake, so there's no loss of torque from a bigger throttle body.

The reason for the factory using a smaller throttle body has to do with part throttle every day drivability, not loss of torque. Think little old lady with arthritis tapping a little too hard on the gas and rear ending the guy in front of her.

As far as flow numbers equaling horsepower, that's true to a certain extent; but there are a lot of other factors to consider when designing an intake. I'd love to know how the C6r race car manages to make 590 hp through two 31.8 mm restrictor plates:

taman86

iTrader: (19)

all great info here

IOwnCalculus

Yeah, but if you've already got a LS6 intake, you a) have an intake manifold worth selling and b) stand to gain less power than anyone still running early LS1 intakes.

This isn't a replacement for a FAST, nobody's arguing that, but it is an attractive alternative to anyone looking at buying a used LS6. I'd buy a used FAST if they existed at this kind of price point, but they don't (at least not that I've seen).

Could I save up for an LSXRT? Why not save up longer and buy an LSA supercharger? And a fully forged big-bore shortblock? And a built transmission, and a new rear end, and a new fuel system, and... Everyone has a limit where they're no longer willing to spend more money on a given part to make more power, either because they're making enough or the incremental gains aren't worth it. On my bone-stock 2000 LS1, I should see some decent gains from a LS6 or Dorman LS2 intake. I might see a little more power by going with an LSXRT, but I'd see a lot more power by spending that $700 saved on a cam and springs instead.

taman86

iTrader: (19)

very well put. im glad there are others that see the world as i do. the same goes for headers for instance. i can pay a few hundred and have very decent gains or pay over a grand and get that extra horse power. if i was trying to achieve an all out performer then ya ok.

tech@WS6store

iTrader: (2)

Very VERY good info man! We are working on having 5 of these setups on hand and ready to go. holley 92tb holley rails and crossover, holley throttle cable bracket. for a VERY stellar price! Ill post a new thread when that happens of course just wanted to say nice numbers!

99 Black Bird T/A

iTrader: (4)

I tend to think of this test very similar to Darth, which intake manifold (defacto destructor plate) chokes the engine the least compared to the barrel cylinder head.

Nice to see the WS6Store offer the Dorman LS2 for sale. I will be ordering TB cable bracket soon.

As a side note my old valve springs were tested today. I will post the data in internal engine tomorrow and show how one set of Comp Cams dual 987 Springs did over 9 years and 60,000 miles of XER fun. Should have pictures of retainers beat on for 125,000 miles of XER cam lobe love.

Tom0613

Doesn't the stock throttle cable bracket work

taman86

iTrader: (19)

awesome! I know you have to sell your vendors inventory, but what about the warr piece like black bird has. it seems to have very good reviews and a VERY reasonable price point for people who are on tight budgets but still want to play the game. just throwing ideas out there

warriorpluto

iTrader: (2)

That's what I got in the mail two days ago. Very quality piece. Didn't break my bank neither. Caught a deal from them too. For less than 160