High hp guys do you guy change valve guides how good are stock guides? Do I need up upgrade my machines telling me to leave stock ones of my valves aren't bent thanks

 

stock are iron and are more durable than aftermarket bronze. bronze do have their own advantages, such as lubricity and less chance of breaking.

 

do alot of people put copper or bronze in on high hp builds? i dont know if my mchine shop leading me in wrong direction.

 

Bronze is tougher, more wear resistant, lower friction, better heat transfer, won't crack and break off if you bend a valve, honestly better in every measurable way, but bronze is really expensive compared with iron. (probably 5x more expensive at the OEM level) Hence their use in the OEM head. If they're worn, use bronze to replace them.

 

I've heard the stock ones cracking and the pieces breaking off...if you got the money I would upgrade to bronze...do it right or do it twice is my motto, I would rather not risk it and then have to pull the head again and if a piece breaks off an intake guide then its going to beat up the piston, chamber, and other valves and maybe even turbo turbine..

 

yeah my question is do they crack out of no where or only if you bend valves

 

Only if you bend valves. The guides and work are kind of expensive, but if the head is gonna be off anyway, it would be good to do them.

 

Have your machinist check guides in your head now. If they are worn, definitely replace them with aftermarket bronze guides.

 

i did i had my machinest check them there still good.... im building hi hp car so i dont wanna cut corners i left stock guides i just wanna make sure there good fior hi hp i dont wanna have problems

 

We always run the bronze guide in a high hp combination. Even low hp! The guides provide less friction, better then lubricating, they dissipate heat better which is a big deal with lots of boost. They do wear faster but I've never seen one come back. And, surely they can become brittle and break from heat.

I really have nothing bad to say about them, except that I've seen some shops install them incorrectly.

 

The bronze valve guides are $4 a peice, so they are not expensive at all. ferrea makes copper ones, and they are about $6 a peice. however, unless you like to run a little on the lean side with high EGT's, the bronze ones are good enough.
so yes, have him change to bronze guides.