RB26 Poncam experiences

[julio]

Just wondering what everyones idle is like with these cams (type-B). Just got mine installed and running and the idle is fairly lumpy and the vacuum is around 13inHg where is used to be ~18inHg with the stockers. Cams have been reshimmed for .45mm intake and .38mm exhaust as per the FSM. It was my understanding that these cams were supposed to idle like stock cams. Boost leak checked out excellent too.

[Ramius83]

I would double-check your vacuum hoses and make sure that you do not have a vacuum leak. Just because you do not have a boost leak, does not mean that you don't have a vacuum leak. 5 in/Hg drop seems a lot to me. What degree/duration/lift did you go with????

However, It is normal for the vacuum level to drop a little with the installation of larger aftermarket cams. This is due to the larger duration that the cam allows the valve to stay open. So, the higher the duration, the lower the vacuum, and vice-versa.

[flatrate]

im going to be installing a set of 256 pon cams on my rb25 just waiting on my wheels to get back so i can get it back on the ground... will be doing a dyno test in the coming months... i have searched high and low for before and after results on the Rb25 havent found anything....

[mr.nismo1]

im going to be installing a set of 256 pon cams on my rb25 just waiting on my wheels to get back so i can get it back on the ground... will be doing a dyno test in the coming months... i have searched high and low for before and after results on the Rb25 havent found anything....

Im thinkig of puting mine on but I'm having problem if my Rb25 is an S2 but the cam sprocket looks from a NEO maybe is a hydro but im not so sure.

[flatrate]

neos are solid lifter...

does your engine have an ignitor on the coil pack cover?

[julio]

Was looking specifically for rb26 experiences. As far as boost/vacuum leaks go, I performed both a boost leak check to 25psi and a smoke test and didn't find anything. Besides, no vacuum lines were touched when swapping cams. Just thought it was wierd that the cams would be so lumpy for "drop in's."

[mr.nismo1]

neos are solid lifter...

does your engine have an ignitor on the coil pack cover?

No it doesn't. In the shop there is 2 Rb25det head one is a NEO and the other is a S2 Rb25det. But the s2 intake cam gear has 4 small bolt in front and the NEO has only one in the center, well mine has a one in the center but im not so shure if is a Neo or not. The engine when i bought it was from a 98 r33

[chad b.]

Why would you waste money on a 256 duration cam in the first place? That thing isn't enough better than stock to justify the money to buy it. Kelford cams all the way.

[flatrate]

cause the car will idle like stock, and i got them brand new in the box for just under 500 bucks....

stock cams are 240's and only like 7.8mm lift