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well, your facts are wrong...
Originally Posted by axapowell
(Post 2385494)
The Isky 8805-SP have a seat pressure of 150 lbs. @ 1.875 and 435lbs @ 1.225 Max net lift .650 coil bind at 1.160
The Isky 9905 have a seat pressure of 165 lbs. @ 1.900 and 450lbs. open at 1.300. Max net lift of .600 coil bind @1.160 The Compcams 929 have a seat pressure of 148 @1.880 and 432 @ 1.230 coil bind at 1.160 I don't see why these wouldn't work. Merc is using the Comp929's as far as I know. These are are perfect mate, and a much better spring. No pizzing contest, just a fact. Dave The "tool room" springs you mentioned are soild roller springs with a Inst. presurre of 245psi. Second, if its a hyd. cam, roller or not, you do not want more than 135psi at the seat. Now thats the fact, Jack. |
Well, I guess I'll give Bob Teague a call and tell him he is wrong and you are right!
Man....what was I thinking listening to him and not you... Dave |
Originally Posted by OLSKOOL72
(Post 2385869)
The "tool room" springs you mentioned are soild roller springs with a Inst. presurre of 245psi.
That is NOT true.. Dave |
1 Attachment(s)
See attached specs for 9905!!
Dave |
1 Attachment(s)
Originally Posted by OLSKOOL72
(Post 2385869)
The isky 8005, not the 8805,s have a spring pressure of 135psi at 1.875
The "tool room" springs you mentioned are soild roller springs with a Inst. presurre of 245psi. Second, if its a hyd. cam, roller or not, you do not want more than 135psi at the seat. Now thats the fact, Jack. See the attached FACTS JACK! Dave |
Bob who??
Call whom ever buddy, I go by my Rimac machine, and a depth mike for my spring pressure, not what "somone told me" or something I read in a powerboat magazine editorial.
Whatever, you just emailed the specs on the 8005's, which I was right on and you were wrong. [email protected].. You will have about 130psi, as the inst. height, as after the valve job it will be at the least 1.900. As for your Tool-room springs, I was looking at the same p/n but with an SR which was 245psi installed. Never the less, you were recommending a spring still with a seat pressure of 165psi, which is waaaay to much, as I first stated, before you chimed in again. Maybe its time for a refresher course from Bob.... |
Originally Posted by axapowell
(Post 2385873)
Well, I guess I'll give Bob Teague a call and tell him he is wrong and you are right!
Man....what was I thinking listening to him and not you... Dave lol |
Oh...so now Isky and Teague are wrong and you are right?
Look again at their specs for the 8005... 150lbs@ 1.875 installed height...You are wrong or you can't read. BTW Type of cam...Solid. The springs don't care what kind of cam you are using, the cam specs desiginate the spring rate! I told you I didn't want a pizzing contest, but you have turned it into one. Maybe RMbulder will chime in and straighten us out! Dave |
Originally Posted by later
(Post 2385290)
what lifters are in the 500hps and what lifters should they be replaced with ?
later The 500 carb's use a hydraulic roller cam, lifters and springs, etc. from Crane Cams. The 500 EFI's were changed to a Comp Cams spring, the 929's, but retained the rest of the Crane valvetrain parts. I favor the Isky valve train parts, they are a little more money, but are more durable in the long run. My opinion, and that of my engine builder, I trust him as we go waaaaay back. When we freshened my 500 carb motors we used the Isky 8205 Plus springs with 10 degree locks and retainers, my cams and lifters were fine, only 160 hrs, then we changed the Crane Gold roller rockers out in favor of Crower full roller stainless rockers. Hydraulic roller marine engines are hard on valve train components, using the best you can afford will pay off in the long run. Just my "opinion",,,,,, And opinions are much like a$$holes,,,,,,Everyone has one. :D If you are ready to change the roller lifters I would look at Isky. Again, my opinion, see above reference to body parts etc. |
VALVE SPRINGS
My pick was the ISKY 8205 PLUS. The specs were the closest to what Merc Racing and Crane Cams called for with the original 500 HP camshaft. They were a step down from the real/full blown "Tool Room" springs, but the lightest of the "Tool Room" springs was too much open and seat pressure for the cam at the RPM range we run in. Now that I've got the 500's valvetrain all scienced out, I've gone and switched to the HP 525's in the new boat, and I can start all over again. :D |
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