355 LE Dyno tune this Friday...Guess my numbers
Registered User
Joined: May 1999
Posts: 193
From: Prestonsburg, Ky
Just checked the beehives spring height. They are at 1.780" and Lloyd said to set them at 1.750". If it turns out that I need to reset the beehives then I am just going to put the Comp dual springs in and hopefully eliminate the possibility of spring pressure all together.
Still waiting on the tuner to send them to me. Race weight is going to be heavy at around 3900 pounds. Tuner stated that 3.90 is looking like the best gear for street tires or 255-50-16 ET street radials.
Still waiting on the tuner to send them to me. Race weight is going to be heavy at around 3900 pounds. Tuner stated that 3.90 is looking like the best gear for street tires or 255-50-16 ET street radials.
Sounds great congrates on your car, you should check out some of our posts over on www.kyhorsepower.com about my car and kind of the same problem I am having is very close to yours, but all said and done with Bluecat is one hell of a tuner and a great guy......glad your happy with your results.......
Thread Starter
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Joined: Aug 2005
Posts: 4,405
From: Kantuckee Yo'
Sounds great congrates on your car, you should check out some of our posts over on www.kyhorsepower.com about my car and kind of the same problem I am having is very close to yours, but all said and done with Bluecat is one hell of a tuner and a great guy......glad your happy with your results.......
Banned
Joined: Apr 2000
Posts: 1,444
My heads were purchased before Lloyd started using 918s, so it didn't really apply to me.
(I have 917s and have not run into float issues).
One thing you will want to check is the installed height on the 918's, they were installed on a set of heads incorrectly to high and it just caused him to go into valve float way too early. For my cams 918 beehives need to be installed at 1.750" +/-.010"... THIS IS REALLY IMPORTANT!!!!
Last edited by user 647483; Mar 29, 2008 at 08:53 PM.
Banned
Joined: Oct 2006
Posts: 4,970
From: Goochland, Va.
If your springs are out .030 thats a huge amount.......
I just did a set of heads and I went 150 or more on the seat and really close to 400 open all on a stock rocker/lifter combo. It pulls hard to 7k on a stock cast head.
Not the first set I have done like this.....someone else on the board bought an old set I did, they had really good results too
I just did a set of heads and I went 150 or more on the seat and really close to 400 open all on a stock rocker/lifter combo. It pulls hard to 7k on a stock cast head.
Not the first set I have done like this.....someone else on the board bought an old set I did, they had really good results too
Registered User
Joined: May 1999
Posts: 193
From: Prestonsburg, Ky
Yeah I will link you to both threads, also you have yo sign on and become a member for it to work.....
http://www.kyhorsepower.com/forums1/...howtopic=32611
http://www.kyhorsepower.com/forums1/...howtopic=27302
http://www.kyhorsepower.com/forums1/...howtopic=32611
http://www.kyhorsepower.com/forums1/...howtopic=27302
Registered User
Joined: May 1999
Posts: 193
From: Prestonsburg, Ky
Registered User
Joined: Sep 2004
Posts: 1,872
From: Lantana, TX
The guys I listen to say that installed height isn't just about load even though that is very important, but it is about how close the spring is to solid at maximum valve lift. If it is too far from solid the spring surge may not let the spring control the valve. If the 1.750 installed height gives .050 from solid height at full lift, installing them at 1.80 would give .100 from solid. This would probably have a dramatic effect on surge and valvetrain contol. The guys I get to listen to talk about distance from solid height at max valve lift in numbers closer to .050 than to .100. They build some pretty stout engines so I tend to believe what they say.
Joe Urban
Joe Urban
Registered User
Joined: May 1999
Posts: 193
From: Prestonsburg, Ky
I talk to Bret quite a bit because he just designed my BBC cam and we talked extensively about this and I agree whole heartedly about using the solid state of the spring to help dampen it, I was just talking merely from a pressure perspective that .030 shouldn't effect pressure that much, which is what the OP is worried about. What is the spring rate for the supplied springs? Assuming it's 300 lb/in approx. actuating the valve .030 would equate to a 9lb difference. Bret wanting the springs installed lower has more to do with clearance to coil bind than pressure. He argued his points about this many times on this board.
There is also a link on this web site discussing this problem to, it has me tore all to hell, i spent big money and used peoples advice and tried to order the best combo i could and I have this problem and really don't know what to do its a hard one to figure out thats for sure......
https://www.camaroz28.com/forums/sho...d.php?t=591574
Thread Starter
Registered User
Joined: Aug 2005
Posts: 4,405
From: Kantuckee Yo'
Well clearly my valve springs install height are out of spec by ~.030" or so to the tall side. I hope that this is the smoking gun.
And again since all the valve train would get pulled I am in favor of throwing my brand new Comp 26921 dual springs w/ titanium retainers on at the correct height and throw the pressure issue out the window for good, they are 5/70 stronger than the beehives. Plus I would feel better having dual springs in case one ever broke. This would give the motor a fighting chance at surviving.
Regarding push rods I am using Comp Hi-tech 7.00" in size. According to the sharpie sweep test when I built the motor the PR size is correct. Rocker geometry is dead on so I know its not push rods. This bit me once in the past and wore my guide plates severly. I have been watching the guide plates on this motor from day one and they dont show the slightest blemish of any wear.
And again since all the valve train would get pulled I am in favor of throwing my brand new Comp 26921 dual springs w/ titanium retainers on at the correct height and throw the pressure issue out the window for good, they are 5/70 stronger than the beehives. Plus I would feel better having dual springs in case one ever broke. This would give the motor a fighting chance at surviving.
Regarding push rods I am using Comp Hi-tech 7.00" in size. According to the sharpie sweep test when I built the motor the PR size is correct. Rocker geometry is dead on so I know its not push rods. This bit me once in the past and wore my guide plates severly. I have been watching the guide plates on this motor from day one and they dont show the slightest blemish of any wear.
Last edited by wrd1972; Mar 30, 2008 at 09:32 AM.