thanks but I've seen that one before, I was looking for the one with the FAST 90 on it?

 

you talking the car ls2 mani? would there be any torque loss with the tb right on top of the vic jr. that setup wouldn't cost much to do i think. no mods to the water pump and all. and i could start with my stock tb for now and up grade later. how much was the downdraft adapter? (pm if needed)

 

The FAST LSX tested is the "FAST 90"...

"Made from space-age polymer plastic, the new FAST LSX multi-piece component intake manifold for the C5 and Z06 Corvette shows a 20 horsepower increase on the LS1 engine and 15 horsepower on the LS6 engine, with no loss of driveability or low rpm torque. Best of all, the FAST space-age plastic polymer intake is 30 percent stronger than the stock polymer unit. Unlike aftermarket aluminum intakes, the FAST polymer intake avoids becoming a power robbing heat sink.

The LSX comes with integrated nitrous oxide injector ports and the ability to accept a larger than the stock (75mm) throttle body for increased fuel flow. In addition, the LSX manifold has the capability to be ported and is easily accessible as a result of the multi-piece design.

Fast 78mm Manifold Part Number: FAS54001

Fast 90mm Manifold Part Number: FAS54003"

Tests number 7 and 8 in the linked article.

 

I don't really remember what Richard charged me for the adapter plate -- I was the prototype guy anyway though.

Yeah, the ls2 version from the cars. As I recall, the "truck ls2" is a truck manifold with a 90mm neck (unless that has changed). What was tested in the manifold comparo was the car version.

 

I don't remember either


Seriously though:
This topic has many tenticles but I'll try to highlight some of the major items.
First, I consider the intake manifold to be a "tuning tool" to compliment the rest of the engine combo. There's more than just static flow to consider when making a manifold selection. The runner cross sectional size and more importantly the length have an impact on the torque range of the engine. Throttle body size come into play at higher rpm levels. Small engines generally don't have much low end torque to give up especially in a truck, and a high rpm manifold like the Victor would reduce the low end torque and add some real, real high rpm power. More than likely too high up the rpm range to see a gain in your useable power band and the loss of low end you would experinece would make that manifold choice undesirable.

IMO the manifold/engine combos should follow along these lines.
4.8l/5.3l and 6.0l engines with a stock or near stock cam and heads should retain the stock truck intakes. They don't demand enough airflow to warrant shorter runner lengths and higher airflow rates.
Once the engine and other related driveline mods are added, the manifold options become a little more diverse. Larger displacement (370-427ci) engines can more easily utilize a LS6, FAST 90 or Victor w/elbow with shorter duration cams than a 4.8l/5.3l. The smaller ci engines will need a cam somewhere in the mid 220º or larger to fully utilize the higher rpm intakes. Always bear in mind we're tuning heavier trucks and not lighter weight cars here and that makes a difference especially with vehicle useage.

I see Erik has mad a sticky related to intake manifolds. A graphic would help guys figure out what manifold possibilities they should consider to help optimize their combo. More of a "general guidline" of intake selection. I think engine displacements should relate to the corresponding rpm ranges. Rpm ranges are influenced mainly by cam selection. Cylinder head work will have an impact in the mid range and upper rpm area. Other items such as gear and converter are also important to intake selection and should be noted. Since manifolds are a nice tuning tool this would help narrow down the selection process for given engine displacement and rpm range.

Intake manifolds are an extremely important decision to the modding process and I'm pleased to see some heightened interest in this subject. I only wish some intake manufacturers would step up and offer an improved manifold that would bolt onto our trucks.


Comming up:
Although I'm not at liberty to disclose any detailed info at this time, there will be some valuable engine dyno data related to 5.3l engines happening in the next few months. Hopefully enough data to satisfy both N/A and F/I applications. I want to explore the power potential that the 5.3l engines are capable of and this opportunity will be invaluable.


Richard

 

Hey richard...Do you need a donor 5.3L?? I know someone who recently took his out of his truck and would gladly donate it for the better good of research and science!
Let me know richard and it's yours!

 

Thanks for the offer chief. I'll keep it in mind. I think we're ok at this point, but if plans change I'll let you know.

Richard

 

so what if you had a 5600 lb tahoe that was awd with 31"ish tall tires and 3.73's with a 383 stroker 228/232 6** 6** lsa 110 +2 long tube pacesetter headers and stock for now 317's? not that thats what i have or any thing like that strickly hypathetical