Why don't you take out the current cam, replace it, and then sell it?

 

See this thread:https://ls1tech.com/forums/generation-iii-internal-engine/758380-fast-90-90-smaller-camshafts.html

 

The ported intake will show you similar (and more than likely greater) gains in the higher RPM range than the larger cam in question would provide, but it wont come at the expense of a slightly softer bottom end (cams are always a trade off....more peak power means less low end grunt). Obviously you will take a small hit in fuel economy as well with the additional overlap from the larger stick. Drivability and tip-in will also suffer. Some of the negatives of the cam swap could be cured by higher static compression but that would require cylinder head removal and refacing, obviously not a consideration here.

Besides the additional lope at idle (whether that floats your boat or not or weighs in on the decsion), the cam swap offers the most compromises for similar peak power gains. There is something to be said about a car with great driving manners that lays down a number and its very possible to make BIG power with smaller cams....the trick is in hitting all the smaller details (which add up) to make it happen. The end result being a very powerful car thats a pleasure to drive every day. If making big power in a stealthy package is one of your goals, the ported 90/90 induction is paramount because it represents one of the largest gains you can purshase without negatively impacting low speed engine response, drivability, and power. The only thing usually hurt is the wallet but those tend to always heal up over time...LOL

Also, I failed to mention how the SOTP and throttle response increase from the 90/90 set-up make it the clear winner (IMHO) as it will add to you driving experience every day where the larger cammed stock intake will actually detract from it.

Good luck Phil....let us know what you decide

Tony

 

i think after that statement it is pretty obvious what he will decide. good luck with the 90/90 swap and let us know how you like it!

 

I liked my "just drive it downhill idea" but Tony M. seems to be able to quantify the results of a ported 90/90. I certainly noticed a SOTP improvement with a 230-236 112 on my 346 motor.

 

Yeah ported fast. it made 20hp all over the place on my car.

 

My Mamo-ported FAST 90 gave me a 29 rwhp gain over the LS6 intake with ported TB. That was with AFR 205 heads and a small 215/230 .600/.578 117LSA CheaTR cam. (see dyno sheet below) Going from a 228R to a TV2 is going to give you MAYBE 10 rwhp gain. That's not really a big jump in cam IMO. A FAST 90 will give you a bigger gain with no downsides (besides a lighter wallet).

 

Between what Patrick and Tony have said and found, it would seem the FAST 90/90 may be better overall.

The part about installing another cam that worries me is that will make it the forth time the motor is apart. ( re-ringed at 9500 miles, and two cams)

The FAST I can install ( with WKMCD's help )

The feel im getting is bottom line, Ill make more power upgrading to the port 90/90, than upgrading from the 228R to the TV2.

Anyone want to buy a cam kit ?

Patrick, your dyno is the same day, just switching manifolds from LS6 to ported 90/90 ?

 

Same dyno, one day apart, but with very similar weather conditions. We swapped the LS6 intake, epoxy-ported stock TB and stock MAF for the Mamofied FAST 90, Nick Williams 90 TB and SLP 85mm MAF. Not sure if the MAF gave me any more power, but it made no sense to keep a 75mm MAF on there when I had a 90 manifold and TB.

 

Come on down. I just got a new BFH!

 

Tony spells it out very nice for us in the Corvette forum.

If you will Tony, can you paste it in here. I dont like cutting and pasting others work from one forum to another if im not the writer

 

I think this is the post Phil is referencing above....

That actually is an old wives tale....but a very prevalent one on this board and others.

My ported 90/90 package was a key contributor to my former bonestock 346 short with a 224 cam producing 475-480 RWHP on a regular basis depending on what time of day and who's dyno we might have been testing on.

The FAST 90 is a good piece.....and a ported FAST 90 is even better. It works in practically every application it's applied (mild to wild). Your cylinder head flows more air "net" to the cylinder (with some of the intake restriction removed) and you make more power.

To understand its value a little better its essentially like bolting on a cylinder head with an intake port that flows some 15-20 CFM better....thats the typical increase in net intake port flow when tested thru a ported FAST runner (versus an LS6). A stock out of the box FAST will increase net flow around 7-9 CFM which isnt bad either. Dont forget that these gains are over an LS6 intake which is 6 CFM stronger than an LS1 or LS2 intake.

For example...

Take say an AFR 205 head that achieves peak flow at .600 lift with a radius plate in front of the intake port (some shops use clay). This is the way most published flow figures are achieved. Lets call it 300 CFM @ .600 when tested on a 3.900 bore size which most LS1/LS6 engines are built on.

Now remove radius plate and actually flow the same port thru an LS1 intake manifold. At the same lift point we are now flowing (gulp) 254 CFM! How's that for a wake up call....

Swap to an LS6....Things are looking a little better at 260 CFM but we are still down 40 CFM.

Swap to a FAST (unported)....looking better yet at 268 CFM

Now bolt on a ported FAST and we are getting alot closer to our theoretical best (mathcing a radius plate) at 278 CFM. While that may still sound like its aways from 300, losing only 22 CFM thru the intake is quite good. A standard 23' SBC would need a properly ported race style single plane intake to match that type of loss.

If you were to add a well designed sheet metal or IR style intake you may reduce the restriction another 10-12 CFM but its shorter runners will only benefit the end user at very high RPM's and its no longer in the realm of this discussion.

Note that power output will go up accordingly with every move to a better (less restrictive) intake....usually worth 1-1.5 HP per CFM....you guys can do the math.

Hope this helps and gives you guys something to think about

Cheers,
Tony

 

 

I bought a 90/90 set up today