Generation IV External Engine - Engine Dyno Testing LS3 Intakes INSIDE!!

After swapping intakes for the last 3 days we finally have some data for you guys. These tests were run 2 different ways, once with a maf in place & the test I'm posting which was speed density. The speed density showed power gains that the 85mm MAF was holding back. As a result I'm only posting the Speed density results. If your getting a upgraded intake you really should consider a 100mm maf or speed density tune to see decent power gains.

Here's a few pics of the intake testing:

http://www.precisionracecomponents.com/portedls3install1.jpghttp://www.precisionracecomponents.com/fastintakeinstall.jpg

Results:
http://www.precisionracecomponents.com/ls3intakeshootout.jpg

Differences:
http://www.precisionracecomponents.com/intakedifferences.jpg



For the 2010 guys these results should be pretty close to what they'll see. Using the speed density best simulates the large MAF the LS3 cars ship with!!!

Camshaft was a TSP 233/240 112+2. Basically it was the last camshaft in the motor so we just left it in! :)

Jason,

Sent you a pm.

So modist gains over a ported Ls3 intake, How do you think this would work on a larger cam with ported heads?

I just put one one my car ill be getting it tuned this weekend if the rain holds out
then im going to try to get to the track next week for a few passes

What size TB was used?

Looks like some good numbers. I wonder how it would compare to a Stage 2 Ported LS3 Intake...

What size TB was used?


90mm for LS3
102mm for FAST

Nice info! :thumb:

Thanks for the comparason!

So from the looks of it.... its not worth the $8-900 asking price..
It looks to have a lil better flow from 3700-4700, but up top about the same with out being able to zoom in on the graph... I think ill just port an LS3 and save the othere $5-600.

Kyle

BTW this is external Gen IV

thats what i was thinking!!!

So from the looks of it.... its not worth the $8-900 asking price..
It looks to have a lil better flow from 3700-4700, but up top about the same with out being able to zoom in on the graph... I think ill just port an LS3 and save the othere $5-600.


:confused:

If you have a stock car or maybe just a cam than yeah I guess it's not worth it.. but we are yet to see results on any of the bigger cube motors or even one with ported heads :nod:

I'm still on the fence with this. I still have the 85mm maf so maybe I just go SD? I'd like to see results on a big cube motor..........like mine.

I'm definitely on the fence also. I'm keeping my ported LS3 for now.

Can't wait for a bigger (402ci+)engine to try this thing out, That'll make it or break it for me anyways. My situation is a bit diff though... I don't have an intake at all right now. So I spend what $200 if I got a good deal on an Ls3 then have it ported $300, only about $300 more or so diff to get the Fast. You guys over at Texas Speed don't have any of your 418's you can throw one of these on lol. I'm sure it's just a matter of days before someone has some numbers on a bigger engine. Patiently waiting....

Every single result I've seen shows that the L76/LS3 intake works fairly well on 6.0 engines but becomes a limiting factor on the larger builds. The smaller motors consistently pull 500 more RPM than the larger builds all things being equal. FAST is going to have one HUGE pile of plastic on the shelves if the intake doesn't perform better on thet 402+ builds. :bomb:

build is in sign but should i go get my ls3 ported or get this new intake?!?!?! i am most likley going to port heads and maybe some bottle!!

build is in sign but should i go get my ls3 ported or get this new intake?!?!?! i am most likley going to port heads and maybe some bottle!!

I would port it for now and save the cash. You can always sell it and get a FAST if it proves to be noticeably better on modded engines.

Every single result I've seen shows that the L76/LS3 intake works fairly well on 6.0 engines but becomes a limiting factor on the larger builds. The smaller motors consistently pull 500 more RPM than the larger builds all things being equal. FAST is going to have one HUGE pile of plastic on the shelves if the intake doesn't perform better on thet 402+ builds. :bomb:

Everyone talks about how this intake is going to perform on "bigger cubed" engines. I say :bs:

After all, it's called the FAST 102 for LS3's. You would have thought they would have spent their R&D budget around results produced on a 6.2L engine.

Someone with a modded LS2 or LS3 will eventually get one-but for now based on the initial results, I don't think anyone including myself is ready to bite the bullet.

I wonder how a stage 2 port and 95mm TB stocker would have did.

I will be putting on a Fast 102 and 102 tb in a week or 2 to replace a Jeremy F ported LS3 intake and Fast 92 tb on my 427 w/PRC L92 heads. The results will be seen at the dragstrip not a dyno because I dragrace! I'm hoping to pick up about .15 sec in the 1/8 mile.

do you have a reason to think your going to gain that much? proof?

do you have a reason to think your going to gain that much? proof?

When i switched from an 85mm maf to a 100mm maf it picked up about .15 sec so i would think the 92mm tb is a restriction on a 427 motor with good flowing heads.

Subscribed.

Curious how this would perform on a 400+ CI engine. What is the going rate for a regular LS3 intake?

The speed density showed power gains that the 85mm MAF was holding back. As a result I'm only posting the Speed density results.


Can you share with us how much power was gained going speed density??

so the LS3 engines have a bigger MAF than the LS2's. Didn't know that: will the LS3 bolt into a LS2, plug n play style? I am loath to deal with an aftermarket MAF when they are such a sensitive item and the OEM's put such effort into making them-- no aftermarket company seems to have gotten it right yet with all the claims of guys switching back to stock just to get there A/F ratios correct.

:confused:

If you have a stock car or maybe just a cam than yeah I guess it's not worth it.. but we are yet to see results on any of the bigger cube motors or even one with ported heads :nod:



There just isnt enough results yet to prove this intake is worth the $$.

Im sure quite a few of us will keep our eye's on this.. so far its not looking good.

Kyle

Hey Guys,

Don't want to hijack this, but I thought you all would like to see these results.

The bigger everywhere lines are the L92 truck manifold, the lower lines are a stock LS3!!!!

Talk about dissapointing. These are on a 427 with LS3 heads and a 230/240 cam. This is all through a 85mm descreened truck MAF.
I did notice that the truck intake was pegging the MAF sensor starting at 5800, the car manifold only did it above 6200!!!!

That is some interesting information. Those intakes were both un-ported?

Very interesting ^^

How do the single plane manifolds for the LS3 compare to these?

Talk about dissapointing.

I know my ball rolls slow but what am I missing?

It looks like it picked up a substantial amount.

I know my ball rolls slow but what am I missing?

It looks like it picked up a substantial amount.

Yeah, we were hoping the LS3 manifold would pick up the top end, or at least it would be better somewhere!!!

So how do the carb style EFI single plane manifolds compaire with the elbows on them to these plastic style manifolds? Like the Edelbroke Vic manifolds or the GMPP manifolds? Does anyone have any back to back dyno results to compaire these to the stock style LS3 manifolds?

I want to know if I should be looking to replace my intake set up.

So how do the carb style EFI single plane manifolds compaire with the elbows on them to these plastic style manifolds? Like the Edelbroke Vic manifolds or the GMPP manifolds? Does anyone have any back to back dyno results to compaire these to the stock style LS3 manifolds?

I should know the answer to this in the next couple of weeks.
We have a sprint car coming to do some chassis dyno testing. I will try all of these out on it. That way, I know if it truly makes a difference or not.

Cool keep my in the loop. I am turbo charged now and I have been toying with the idea of switching to a LS3 manifold.

So how do the carb style EFI single plane manifolds compaire with the elbows on them to these plastic style manifolds? Like the Edelbroke Vic manifolds or the GMPP manifolds? Does anyone have any back to back dyno results to compaire these to the stock style LS3 manifolds?
i dont have a back to back, but here is a dynograph of the l76 with weak patriot golds(weak for stainless l92 valves), vs gmpp single plane with 420lb better valve springs different injectors rails fpr, and yella terra rockers. Edelbrock ported "tight" elbow... i might also be missing one more thing not sure

http://www.ls1tech.com/forums/attachments/dynamometer-results-comparisons/152792d1225850233-408-ls3-l92-467-460-dyno2.jpg

If you cut the cowl will the truck manifold fit?

I can hardly make out the dyno but it looks like it is much better up top with a little lose down low. Can you give any number differences in HP and Torque? I can not realy see well enough to tell.

it made 470rwhp@6000rpm with the l76 flattening off after 5000 w weak lifters and weak valve springs started floating mid 6000rpm

503rwhp@7200rpm better springs morell lifters single plane with ported edelbrock tight elbow

not exactly a L76 vs GMSP intake comparison but u still get an idea oh how the single plane performs in the rpm. i think the l76 would have thrown down some better numbers with the better springs and lifters

Hey Guys,

Don't want to hijack this, but I thought you all would like to see these results.

The bigger everywhere lines are the L92 truck manifold, the lower lines are a stock LS3!!!!

Talk about dissapointing. These are on a 427 with LS3 heads and a 230/240 cam. This is all through a 85mm descreened truck MAF.
I did notice that the truck intake was pegging the MAF sensor starting at 5800, the car manifold only did it above 6200!!!!

Interesting - because in a different thread, they put the truck intake and the car intake on a flow bench and found the truck intake to pose a restriction up high. For the life of me I can't find the thread right now - but it was fairly recent. So I don't know if it was talking about the LS3/L92 truck intake or the LS2/LS2truck intake?
Either way - good news for me selling my LS2 truck intake! :)
-bob

When I was at the SEMA show I talked with the guys about the new FAST intakes. For my application he said that the truck manifold made 20+ more HP than the short version.

That was interesting to me.

There are guys deep porting the truck intakes to get rid of the restriction. They are cutting these manifolds in 1/2 to do it. I'd like to see if one of these manifolds can be put in an f body, I've been told they just don't fit, even with cutting the cowl. :(

Found the original thread I was referencing:

http://www.ls1tech.com/forums/generation-iv-external-engine/686006-l92-l76-intake-manifold-flow-comparison.html

In that, it stated the L92 truck intake flowed less than the car intake - the opposite of what was found in the tests above. It does make intuitive sense that a larger volume plenum will breath better - just an interesting disparity between dyno testing and airflow testing. In the end, power at the wheels will always trump airflow cards.
-Bob