Pedestal mount limits

Mr.Slave · 05-15-2008, 08:03 PM

I have the old twisted wedge heads with the pedestal mount setup. I know these are weaker than the stud mount, and I'm wondering the limits. I will have 140-150lbs on the seat and 380-400 open with the cam I have, Do you guys think I'm going to run into problems? I tested the springs and they are up to it, just not sure about the rockers staying put.

qkjuicedpony · 05-15-2008, 08:05 PM

They should be fine.

coupe · 05-15-2008, 08:08 PM

The limit is the small-ish bolt holding them in. I would recommend a stud. The spring rate sounds high or your cam has alot of lift. Tell us more about both.

Mr.Slave · 05-15-2008, 08:38 PM

The cam has .553 int. 221 dur @ .050 and .524 exh dur 228 @ .050. I called the cam builder (cam motion) and they gave me those spring rates.. what other info do you need?

coupe · 05-16-2008, 07:20 AM

The open pressure sounds kinda high for that setup. I would personally go for a stud/guideplate conversion. But qkjuice has alot of valuable experience; he might have tried something similar?

qkjuicedpony · 05-16-2008, 09:40 AM

Quote:

Originally Posted by Mr.Slave

The cam has .553 int. 221 dur @ .050 and .524 exh dur 228 @ .050. I called the cam builder (cam motion) and they gave me those spring rates.. what other info do you need?

With taht cam.More than likely you will wind up pushing the threads out of the head in th eupper rpms.

I would suggest converting to stud mounts.This will require removing the heads for converting.

So if you decide to do this.My honest opinion would be to sell your current heads and buy a set that are already setup for studs.

QWKSNKE · 05-16-2008, 09:20 PM

Quote:

Originally Posted by coupe

The open pressure sounds kinda high for that setup. :

Not really, Both of my AFM cams required more open seat pressure than that. I never changed the springs out but Dale has since he bought my cobra. I'll be interested to see how strong the car is with the stouter springs in it. They do make a difference

SlowJoe · 05-16-2008, 09:59 PM

Quote:

Originally Posted by qkjuicedpony

With taht cam.More than likely you will wind up pushing the threads out of the head in th eupper rpms.

I would suggest converting to stud mounts.This will require removing the heads for converting.

So if you decide to do this.My honest opinion would be to sell your current heads and buy a set that are already setup for studs.

r u drinking check spelling man

Mr.Slave · 05-18-2008, 04:25 PM

I really don't want to spend the extra money on a new set of heads, this build has gone so far over budget its killing me, because I've done everything else twice so far (first build), so at this point I'd rather consider the conversion to stud for my current heads if there's any hope of saving a buck going that route. If I do it that way, is there still a possibility for problems?

coupe · 05-19-2008, 08:53 AM

Quote:

Originally Posted by Mr.Slave

this build has gone so far over budget its killing me,

welcome to the club.

any cylinder-head shop can convert it to guideplates...it's a pretty common deal. They like aluminum too, easy to machine.

Cylinder-Head Service in Birmingham has the experience. You might check Alabama Cylinder Head (Patriot Performace) in Rainbow City-Gadsden area too. They have the ability.

ps: don't forget hardened pushrods for use with guideplates.

05-15-2008, 08:03 PM	#1
Mr.Slave Member Join Date: Apr 2007 Location: Lockport N.Y. Posts: 37	Pedestal mount limits I have the old twisted wedge heads with the pedestal mount setup. I know these are weaker than the stud mount, and I'm wondering the limits. I will have 140-150lbs on the seat and 380-400 open with the cam I have, Do you guys think I'm going to run into problems? I tested the springs and they are up to it, just not sure about the rockers staying put. __________________ 306 stock block, balanced forged internals, main girdle, cam motion custom grind, Twisted Wedge heads, GT-40 intake with port matched lower, 24# injectors, Big Shot plate kit, equal length shortys, o/r x-pipe, CAI, electric fan, A/C and smog delete, all the supporting mods.

05-15-2008, 08:05 PM	#2
qkjuicedpony Dayuuuuuuum!!!!! Join Date: Dec 2004 Location: Dallas GA Posts: 2,933	They should be fine. __________________ 86 Mustang Gt......Mods piling up in my garage. 07 F350 dooly.....Tows my fifth wheel

05-15-2008, 08:08 PM	#3
coupe Super Moderator Join Date: Dec 2004 Posts: 6,313	The limit is the small-ish bolt holding them in. I would recommend a stud. The spring rate sounds high or your cam has alot of lift. Tell us more about both. __________________ " If you can't explain it simply, you don't understand it well enough. " - Albert Einstein

05-15-2008, 08:38 PM	#4
Mr.Slave Member Join Date: Apr 2007 Location: Lockport N.Y. Posts: 37	The cam has .553 int. 221 dur @ .050 and .524 exh dur 228 @ .050. I called the cam builder (cam motion) and they gave me those spring rates.. what other info do you need? __________________ 306 stock block, balanced forged internals, main girdle, cam motion custom grind, Twisted Wedge heads, GT-40 intake with port matched lower, 24# injectors, Big Shot plate kit, equal length shortys, o/r x-pipe, CAI, electric fan, A/C and smog delete, all the supporting mods.

05-16-2008, 07:20 AM	#5
coupe Super Moderator Join Date: Dec 2004 Posts: 6,313	The open pressure sounds kinda high for that setup. I would personally go for a stud/guideplate conversion. But qkjuice has alot of valuable experience; he might have tried something similar? __________________ " If you can't explain it simply, you don't understand it well enough. " - Albert Einstein

05-18-2008, 04:25 PM	#9
Mr.Slave Member Join Date: Apr 2007 Location: Lockport N.Y. Posts: 37	I really don't want to spend the extra money on a new set of heads, this build has gone so far over budget its killing me, because I've done everything else twice so far (first build), so at this point I'd rather consider the conversion to stud for my current heads if there's any hope of saving a buck going that route. If I do it that way, is there still a possibility for problems? __________________ 306 stock block, balanced forged internals, main girdle, cam motion custom grind, Twisted Wedge heads, GT-40 intake with port matched lower, 24# injectors, Big Shot plate kit, equal length shortys, o/r x-pipe, CAI, electric fan, A/C and smog delete, all the supporting mods.