rocker girdle vs. shaft mount

Ive been thinking about ditching my girdles and switching to a T and D set up for my P-51's. I was wondering about pros and cons before dropping 1300.00 bucks. Thanx guys.

Rocker stud girdle is best, that way it gives you 8 studs all bridged together not just a cheap POS like shaft rockers.... JMHO

The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

schmitty wrote:The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

who stud girdle do u like to use on a429 first series

quick 52 wrote:

schmitty wrote:The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

who stud girdle do u like to use on a429 first series

Jomar but you have to call and give them your head numbers their are different heads some are regular and some have clipping issues....

the Coug wrote:

quick 52 wrote:

schmitty wrote:The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

who stud girdle do u like to use on a429 first series

Jomar but you have to call and give them your head numbers their are different heads some are regular and some have clipping issues....

yea i know about the valve clipping at around .700 lift its in the first series of production

quick 52 wrote:

the Coug wrote:

quick 52 wrote:

schmitty wrote:The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

who stud girdle do u like to use on a429 first series

Jomar but you have to call and give them your head numbers their are different heads some are regular and some have clipping issues....

yea i know about the valve clipping at around .700 lift its in the first series of production

NO ... not the first series. From approximate head serial numbers 2,000 to 5,600.

rmcomprandy wrote:

quick 52 wrote:

the Coug wrote:

quick 52 wrote:

schmitty wrote:The concensus is as follows, heads designed for studs are better off left that way and a girdle used. There have been many A head deals that use a lot of spring pressure and valve lift perform without issue with studs and girdles. I would see no upgrade going to a shaft style arrangement.

who stud girdle do u like to use on a429 first series

Jomar but you have to call and give them your head numbers their are different heads some are regular and some have clipping issues....

yea i know about the valve clipping at around .700 lift its in the first series of production

NO ... not the first series. From approximate head serial numbers 2,000 to 5,600.

ok cool. will i pick any power using them running a solid flat 258@ .050 .615 lift spring @ 140 seat 360 open

pick up power is questionable but it will make your top end more stable

quick 52 wrote: ok cool. will i pick any power using them running a solid flat 258@ .050 .615 lift spring @ 140 seat 360 open

You very possibly will pick up some, because the flex will be less on the rocker stud, and you will be getting more accurate valve lift and duration. How much is a guess, and you probably won't be able to notice it, but your valve train will be much more stable. One morning while a bunch of us were sitting and eating breakfast this topic was brought up and the Jomar guys said they would love to see a back to back test done to see what the power advantage was on a dyno, but they couldn't find someone who was willing to sacrifice an engine for such a test at that time.

schmitty wrote:

quick 52 wrote: ok cool. will i pick any power using them running a solid flat 258@ .050 .615 lift spring @ 140 seat 360 open

You very possibly will pick up some, because the flex will be less on the rocker stud, and you will be getting more accurate valve lift and duration. How much is a guess, and you probably won't be able to notice it, but your valve train will be much more stable. One morning while a bunch of us were sitting and eating breakfast this topic was brought up and the Jomar guys said they would love to see a back to back test done to see what the power advantage was on a dyno, but they couldn't find someone who was willing to sacrifice an engine for such a test at that time.

J.A. at Jomar wanted to make a girdle to fit a Jesel system for a big block Chevy and run it on a Spintron to prove a point, LOL.
With regular studs on a canted valve engine, a good girdle is worth 4 degrees of valve timing at .200" with common roller type valve springs. That's easy to check, 'cause I have. Just roll an engine using a stud mount rocker system with a roller cam over with a degree wheel attached ... install the girdle and roll it over again for a new reading. You'll do it ten more times because you won't believe it at first.