Trust me i know this has been beat to death!, but i am trying to figure out what would be the absolute 100%,best of the best cam for the spray.The application will be the usual bolt-on, 100-150 wet shot, but what cam would absolute eat up the juice?i would sacrafice n/a power for better no2 power.

-what would be the extreme?i understand its better to have more exhaust duration that intake duration, but to what degree.take for instance the infamous 231/237, it has 6* of split duration, what would be the most you could go before it's non-sufficent, say 10*-12* of split duration(234/244)???

-and is it just as good to have the lift seperated as much as the duration, or is it better to have a tighter lift?

-and ive found that i definately want it on a 112 lsa, i know people generally go higher, but i still want to stick with this.

thanks for all the help...

 

For a 100 to a 150 shot any cam is going to be good. You won't see a significant differnce until you start spaying 200+.

 

Try a TSP 231/231 or 233/239, a g5x3, or anything similar.All of these cams love the spray.

Nate

 

so how does the rex like the juice?

 

Well, there is a somewhat perfect cam for each specific flow of heads, but I doubt too many of them would be a 112*LSA, so your defeating yourself off the bat.

FWIW My cam has 11* separation, a lift difference of .0185 in favor of the intake, and 114*, my cam was ground specifically for my application, head flow, and for a 300shot.

 

(same person as poster)
well the heads will be stock 241 castings, i want to get the most out of these, b/c ive seen too good of numbers out of cam only cars to throw a set of heads on there, especially if im going to spray, that SHOULD be enough power for my needs.im not dead set on the 112, but i want an aggressive idle, so what would you suggst roughly on specs per say?keep in mind i dont want to have to fly cut the pistons....

 

I would rather have you contact Ed Curtis, EDC on here. If you are interested I can send you his cam request sheet and email address. He'll take all the info in, as well as your special request for a lopey idle etc., and then let you know whats up. Never heard anything bad about his cam's, mine is in the new engine waiting to be installed with other goodies very soon.

 

please do thanks....

 

112lsa isnt an ideal LSA for nitrous...So that just throws your whole PERFECT part out the window..

Mike

 

well the 112 would be kind of the extreme lsa to go, definately not lower, but i would be open to diffrent lsa's, if someone where to explain the reasoning why another would be better considering my application.

 

My ultimate goal is bascically have the biggest cam, that will benefit the No2, that wont totally make the car run like a turd, and not have to twist the snot out of it to 7500 rpm, is this doable?

 

i recentlyspoke with one of our sponsers, and this is the cam he reccomended for my specific application.

comp cams 232/240 .583 .610 114 LSA. what do you think?

he said this will not need to be fly-cut, and with my boltons(lsx90/90, kooks 1 7/8, i should be around 420rwhp n/a.does this ound right.this is a modified version of the CC-I-6.

 

ya, the rex is a nice cam, but they donr look very consistant to me ive seen anywhere from 370-460, i just dont understand sometimes.but with 528rwhp, and 580rwtq, it isnt doing too bad huh?, is that a 100 or 150 shot?

 

Not sure why you say that, my cam was built for my application by allen at futral, told him my entire setup and he built me a cam for it, and mine's on a 112, so like I said, not sure why you think that would be a problem.

 

Well, Generally speaking an off the shelf cam in a 112* will not have the ideal valve timing to maximize the nitrous. Not to say that a 112* wont work with Nitrous, they do, hell I run a TSP 231/237 112* in my A4. I bet if you took your specs, and reground the cam to a 114 or 116* you would pick up some noticeable horsepower using same size shot, Bet! Now, go with a custom ground cam, and almost all will come out with min of 113* but most use 114* or 115* LSA. I had three different grinds from Cammotion, two 114* one 115* and now the Ed Curtis cam, also 114*. These are cams designed to MAXIMIZE nitrous use, and not little beginner 150 and smaller shots. I am not an expert, but have learned from this site and asking these same questions. Besides the LSA, built into the cams valve timing is how much cylinder pressure is built.

 

This is the cam im going to go with.
FM-F6-114 FMS Custom Grind Camshaft - 226"/230" .575"/.595" 114LSA - semi-aggressive profile with a 2000-6800 RPM range, fair idle

 

Yeah, I gave Allen my setup, 374 cubes, (at the time I didn't know what heads I was gonna have, so I told him afr's would be in the future), turbo 400 with 4000 nitrous converter, 3.73 gears w/ 28 inch tire, and planning on spraying a 300 - 350 shot, and he came up with a 246/257 .632/.645 112+4 cam for me, didn't look at the cam card to see if it's actually a 113 or anything, but those are the specs he gave me.

 

Sounds like your definately I light-weight there Devon. My cam is based off nearly full street trim weight of 3350 with driver, your car is probably about 3-400less, which also makes a difference. Sounds like one helluva cam there. I was going more for a comfortable daily driven single digit midget.

Charlie

 

Some of you guys might be approaching the cam selection from the wrong end. You don't choose LSA first, nor do you choose the intake/exhaust split first. You need to determine where you want to make peak power first (this will determine intake closing point), then you'll want to determine how much nitrous you're going to spray and how much overlap you can tolerate (this will determine everything else).

If you're strictly going for nitrous performance, you'll want to open your exhaust valve earlier than you would NA. Nitrous burns a lot faster and by opening the exhaust valve earlier, you will lower your pumping losses and gain power. You won't need tons of overlap nor a lot of intake duration since nitrous is boost in a bottle. If you don't want the car to be a turd at lower rpm, then you'll want the overlap close to some popular cams out on the market. I'll take my favorite, the FMS F-13. 230/232 112LSA 110ICL.
This cam has overlap of 7 degrees at .050". This is the max overlap I'd recommend to keep the 346 from being a "turd" down at lower rpm.
Intake closing point of 45 degrees ABDC (which will peak at 6300 NA and pull to 7000).
Exhaust opening point of 50 degrees BBDC (very good for NA, but nitrous needs an even earlier opening)

Using the F-13 as a guide, I'd recommend the following.
230/240 114LSA 110ICL
Overlap at .050" is still 7 degrees (just like the F-13)
Intake closing point is 45 degrees ADBC (just like the F-13)
Exhaust valve opening is 58 degrees (8 degrees earlier than F-13. Not as good for NA, but better for a 200 shot or greater).
240 degrees of exhaust duration would give the greater volume of exhaust gas additional time to evacuate the cylinder.

On a side note, you could achieve similar critical valve events with a smaller cam.
224/236 116LSA 113ICL
Overlap is -2 degrees at .050" (very smooth)
Intake closing point is still 45 degrees ABDC.
Exhaust opening point is 57 degrees (outstanding for a 200 shot or more)
236 degrees of exhaust duration is still pretty good for a nitrous shot.

Remember, choose the valve events you need first and let the specs fall where they do.

 

How in the hell are you getting 3350 with driver in full street trim!!!!!! I'll be lucky if i'm there, lookin at somewhere in the 3100's for the car and i'm 270! I have some stuff out, but left most of the safety stuff for driving it on the street in (bumper supports, side impact supports, etc.) And yeah, it should definately be a nice lopey cam, hehe!!!