Any idea about S2s vs Kelford 272s? My setup is Buschur 2.3 with buschur stage 3 head with a FP BB Green on an IX. Piston hit the valves and I will probably need atleast the intake side cam.....came across this and maybe I'll buy the S2s instead of staying Kelford 272.

 

i will have 2.2 manley stroker, kelford 272, map O2 downpipe. so what turbo can i buy to have good spool and 450+ hp??

 

I have an FP BB green and it spools awefully fast!
On 91 it made 435 whp and E85 it made 525whp.....both conservative tunes....

 

Question is what caused the valves to kiss your piston? You're Kelford cams were not the issue unless you snapped off the MIVEC cam gear.

 

IT jumped time, still figuring out how that happened.... Assuming I'll find out when replacing all of the timing components.....no glaring issues seen so far. Cams weren't the issue but the intake side is probably going to have to be replaced. All cam gears are still attached. Hopefully I will hear tomorrow from Buschur since he has the head now.

If I need to replace it should I go GSC S2 or stay Kelford is the question?

 

GSC's!

 

Assuming you liked the way the car ran before it had a problem why would you consider a change? Both are good cams and you will not be gaining much if anything by changing them. Unless you just want to try a slightly different cam and get retuned in the process.

It's going to be interesting to see what DB 's shop finds out. Just might want to ask Dave what he suggests.....he has been around the industry for a few days....


Here are some articles for your researching interests.....

https://www.evolutionm.net/forums/ev...ord-280-a.html

and

https://www.evolutionm.net/forums/ev...d-updated.html

 

Yeah, I'll definitely ask DB his opinion. If I have to replace the intake side I could do just that or go with something that might be better....albeit won't be a huge difference. Either way the car needs to be retuned. I asked Rob and he was going to use GSC S2 cams but know one had them in stock so he went with Kelfords. There isn't any reason not to go with the Kelfords but if I have to buy a new one and I can get a pair for a "deal" and the should make a few more ponies then I am game...well seeing as how it as to get tuned anyways.

For the 40 miles I drove it it felt great....well the little I was able to get on it. There is really no reason to change....just kciking around ideas since I have the whole motor apart. All depends on how much the damage is gonna cost, but there are always things to try.

I can tell you or show you what they will find out.....Every intake side valve is bent and most of those rockers are broken. The head is cracked but it is in a non stressed area so they can weld it and push it back and the intake cam is scratched.
Atleast the exhaust side is fine.....so it seems. Was talking to Nick at BR and all the stuff they have to do isn't going to be cheap. I am hoping it won't cost too much since I just spent $25k plus shipping and all the other stuff but we'll see.
PM me if you want pics of the damage.
Thanks for the links.

 

Great thread, but it revolves mostly around 272 cams. ( I am really happy with my 272 Kelfords BTW)
I'm strengthening the bottom end of my 9 TT/HPDE track car.
I was at 401/376 with Kelford 272's and a BB green, 93 pump on Iveys dyno.


I usually shift by 7K but will run it to 8K when a shift is inconvenient.


My question is with say Kelford 280's how much will it shift the power to the right if at all, and will the gain to 8 / 8500 be worth the trouble / offset the loss at 3700/ 4000?


9:1 comp CP pistons, beehive springs, Carrillo rods, bowl ported head, ferrea valves.


Thanks
Shoe

 

There is a big jump in effective duration (12 deg) between the Kelford 272 and 280, and that will definitely worsen the idle and soften the spool characteristics. As always, the question is will that offset any power improvement to be made further to the right, and again as always, the answer largely lies in the size of the turbo.

Given your configuration, I would be hesitant to make that swap. And if I were bent on doing that, I'd probably opt for the GSC S2, which falls right between those two, and offers a good compromise.

 

Or the R2s since it sounds like he doesn't really rev the motor high enough to make use of 280s.

 

I care less about idle quality as it's not a street car.
I don't rev it that high because it's done making power. Well it's flat from 7200-8K.
I typically only run it to 8K when I would lose time by shifting then downshifting.


I would have no problem spinning it to 8500 if it made power all the way. A big shift to the right in power may mean an extra downshift in a few corners but if I lose a few hundred RPM to the left and gain 1200 to the right seems like a win. On paper any way, and assuming reliability does not take a big hit.


I just don't hear much about road racers running 280's.
And I'm not sure of the gain switching to S2's or JUN 272's over the Kelford 272's.


That's why I'm asking.


Shoe