85lbs at the seat? 467 XFI cam
#1
85lbs at the seat? 467 XFI cam
Well gee no wonder my car was having issues above 5500RPM. I had my valve springs measured and they were at about 85lbs at the seat. Don't know how that happened but either way Comp Cams recomended I go 145-150lbs at the seat if I go with a double spring which is what I want to do.
I'm just wondering what are you guys running with this cam. I have 1.7intake and 1.6exhaust T&D Shaft rockers by the way and those wonderful Comp-R lifters with about 6000KMS and no problems........touch wood.
I'm just wondering what are you guys running with this cam. I have 1.7intake and 1.6exhaust T&D Shaft rockers by the way and those wonderful Comp-R lifters with about 6000KMS and no problems........touch wood.
#3
I'de be more worried about what kind of damage the valve float did. I would atleast pull the intake manifold and make sure the lifters are ok and try to check the cam lobes through the lifter bores.
#4
Supposedly these springs ( Comp double spring ) had about 130lbs at the seat when they went in. Originally I was gonna run a Comp 305 cam so I think he sprung it with that in mind and never changed them when I decided to go for the 467.
I don't HAVE to run beehives do I?
I don't HAVE to run beehives do I?
#5
They (beehives) solved my valve float that was happening with the 987s.
#7
The XFI lobes are rather agressive and were designed specifically to take advantage of the beehives strengths.
The 1.7s are going to make those lobes hell to control, IMO you need to start thinking before you buy but maybe a set of 120 beehives will patch it together for now.
The 1.7s are going to make those lobes hell to control, IMO you need to start thinking before you buy but maybe a set of 120 beehives will patch it together for now.
#8
Well, my head porter measured the springs on the bench today and got 115lbs. The other measurment was on the car and although it was not as accurate, it did tell us my springs were screwed.
It's hard to believe that there is not a dual spring that would work in it's place. The Comp tech said 145-150 at the seat would do the trick but that seems a little high to me for a hydraulic lifter.
It's hard to believe that there is not a dual spring that would work in it's place. The Comp tech said 145-150 at the seat would do the trick but that seems a little high to me for a hydraulic lifter.
#11
Well, my head porter measured the springs on the bench today and got 115lbs. The other measurment was on the car and although it was not as accurate, it did tell us my springs were screwed.
It's hard to believe that there is not a dual spring that would work in it's place. The Comp tech said 145-150 at the seat would do the trick but that seems a little high to me for a hydraulic lifter.
It's hard to believe that there is not a dual spring that would work in it's place. The Comp tech said 145-150 at the seat would do the trick but that seems a little high to me for a hydraulic lifter.
Stock lifters will handle 140+ just fine.
IMO the 145-150lbs would be minimum on the seat pressure you need with beehives given a 1.7 rocker on XFI lobes, if you want to use a dual spring you will need to go higher yet. I look at this as setting it up a little extra stiff though for two reasons, one you can't have too much control and two the springs will lose a little something as they break in.
#14
UPDATE: Well I finally got a set of 987 Comp cams double springs in my car today and she FINALLY revs clean to 6700RPM which should be more than enough with the 467 XFI cam in there. They were shimmed to achieve 150lbs at the seat and I believe a little over 400lbs open.
A special thanks to all who gave me input on this.
I can now FINALLY get some dyno numbers and hit the track too!! WOOT!!
A special thanks to all who gave me input on this.
I can now FINALLY get some dyno numbers and hit the track too!! WOOT!!