LS2 vs Fast 90 dyno comparison
TECH Enthusiast
Joined: Mar 2004
Posts: 647
Likes: 0
From: Australia
That does it. Im getting my LS2 ported. I prefer the mid-range gains over the FAST anyhow. I got a stock LS2 intake atm. and already run 122+MPH. If the gains are more than going from LS1 to LS6 then I can expect another 0.2s and 2mph.
Not to start anyting, but my ported fast 90mm from LME doesn`t keep up with my 408 with ET 245`s. Power stops pretty early. From some research I have been told the LS2 flows better with my set-up up top. Vette Doctors from what i was told put a LS2 on a set-up just like mine and it pulled all the way to the top and made about 40-60rwhp more. If so, this would be a cheap fix for my issues other than a sheetmetal intake. I`m planning to call them to justify the results. I was told this by ET also about the results from Vette Doctors. Can anyone answer why the LS2 would work better for my set-up? Thanks!
One of my ported FAST intakes was recently worth 32 HP and 20 ft/lbs of TQ more than a stock LS2 with the exact same throttle body....A-B dyno test conducted on a repeatable SF902 engine dyno in a brand new state of the art dyno facility. Thats a ridiculous gain from an intake swap and IMO just shows how weak a stock LS2 intake actually is. An LS6 combo even with a 78 mm TB would have shown less of a gain....probably closer to 25 HP. Porting an LS2 would have to be worth an insane amount of power to better those gains. Many an independent test shows the LS2 to be one of the weakest out of the box units (and the FAST one of the best). It seems odd to me that the results would be just the opposite ported. Keep in mind the FAST was designed as a performance piece from its inception by a notable expert in the field (Keith Wilson). Alot of the area's I address by porting (not all) are production and tooling issue related that are inevidable in a massed produced piece, with the end results from porting further optimizing the benefits inherent in the FAST design.
I have never messed with porting an LS2 as I feel the FAST just makes for a better "starting point". Most of the higher output combinations are running the FAST (modified or stock) which has to tell you something as well.
Just my .02 based on my personal experience and nothing more...
Tony M.
I have never messed with porting an LS2 as I feel the FAST just makes for a better "starting point". Most of the higher output combinations are running the FAST (modified or stock) which has to tell you something as well.
Just my .02 based on my personal experience and nothing more...
Tony M.
Makes some since. granted my peak numbers where only 485-490rwhp locked, but my TRQ was still over 500. Makes awsome power very flat. I wasn`t use to seeing that compared to my 346 H/C set-up. the fast does really we`ll, just didn`t quite peak where I wanted it to up top. But for a street car she runs flat *** sweet. Maybe some of the things I`m hearing about the LS2 are false! Good info, Thanks!
This is not the 1st time I have seen this. One of the sponsors on here posted about this as well. I pm'd him about it and he basicly said that the LS2 if ported right would equal a ported FAST.
I have been asked who the sponsor was and I cant for the life of me remember. I wanted to think it was Racetech but dont hold me to it.
I have been asked who the sponsor was and I cant for the life of me remember. I wanted to think it was Racetech but dont hold me to it.
11 Second Club
Joined: Aug 2005
Posts: 61
Likes: 0
From: Houston, TX
Great Information, I have seen some nive gains from a ported LS2 intake in the 10RWHP range. Looks like I am not seeing huge gains from a fast instakeon a LS2 block. Nice to know you don't have to hack your engine bay firewall to install a fast when your ls2 ported can give you a better band for the buck 
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Originally Posted by lt1dave
We port the FAST every time we install one. Most of the work isnt in the runner, so it can be done independant of the heads.
TECH Enthusiast
Joined: Mar 2004
Posts: 647
Likes: 0
From: Australia
Ported LS2 lifted the entire power curve from start to end by 13rwhwp on my H/C car. Same day, same dyno, same tune and back to back. Mid-range is way more punchier, and seat of the pants is very noticable, more than the dyno shows. It is more efficient, holding out 100kpa to 6300RPM then trailing to 98-99kPa at 7000RPM.
11 Second Club
Joined: Aug 2005
Posts: 61
Likes: 0
From: Houston, TX
Ported LS2 Intake looking good After reviewing lots of ported LS2 results I would say this is not going away. Since the Fast LSx intake does not fit right into the engine bay of a C6 the ported LS intake makes alotta sense.
It looks like the FAST takes longer to ramp up to the peak power as a ported LS2 runs a line above stock in the 10+ RWHP range across the board. Far better power distrubution IMO.......
It looks like the FAST takes longer to ramp up to the peak power as a ported LS2 runs a line above stock in the 10+ RWHP range across the board. Far better power distrubution IMO.......
Originally Posted by sditch
It looks like the FAST takes longer to ramp up to the peak power as a ported LS2 runs a line above stock in the 10+ RWHP range across the board. Far better power distrubution IMO.......
Note the gains on this gragh below with no other changes except for one of my ported 90 units (same day on the same dyno)....huge gains everywhere and while I have not done a back to back test with a ported LS2, I would put my money on the fact the larger plenum and runner cross sectional areas would provide alot more power upstairs where you spend most of your time driving the car hard. Once again, the FAST was a performance piece from it's inception....modifying it seems alot more logical than one of the weaker performing factory intakes currently offered.
Some day I might have the opportunity to dyno both and will share the results with you guys when I do.
Tony
Last edited by Patrick G; Aug 3, 2006 at 04:17 PM.
On The Tree
Joined: May 2006
Posts: 118
Likes: 0
From: Tampa,Fl
intake porting No one got around to answer the question. How and where do you cut the ls2 intake and how and what do you use to put it back together. How come no one states just how much it costs to port a fast or an ls2? I"m not trying to start a war I'm just sick of the corvette tax especially from head manuf. who cast from unobtainum. Especially when SB heads are all under $1600.
Back to the intakes. I thought plastic is cheaper and easier to mold/cast than aluminum. Almost $800.00 for fast sounds like a part from NASA.
Back to the intakes. I thought plastic is cheaper and easier to mold/cast than aluminum. Almost $800.00 for fast sounds like a part from NASA.
TECH Apprentice
Joined: Sep 2005
Posts: 370
Likes: 0
From: DFW, TX
Originally Posted by twospeed
No one got around to answer the question. How and where do you cut the ls2 intake and how and what do you use to put it back together. How come no one states just how much it costs to port a fast or an ls2? I"m not trying to start a war I'm just sick of the corvette tax especially from head manuf. who cast from unobtainum. Especially when SB heads are all under $1600.
Back to the intakes. I thought plastic is cheaper and easier to mold/cast than aluminum. Almost $800.00 for fast sounds like a part from NASA.
Back to the intakes. I thought plastic is cheaper and easier to mold/cast than aluminum. Almost $800.00 for fast sounds like a part from NASA.
the way i see it is if a LS2 intake can be picked up for $350 LS2, TB for $210, $300 in port work and similar results could be gained for the cost of just the fast 90.
i wonder if these are being cut open and JB welded back together or an apoxy is being used to put them back together. i wouldnt attempt to do this myself, im just curious as well.
