why would i need 10 degree locks ? and other ?s

[CopMagnet5oh]

i'm rebuilding my gt-40 alum heads, just got copper inserts put in the valve guides, going to clean them up good, and then do a valve job, my engine builder suggested i use 10 degree locks and new valve springs, i understand about valve springs, but do i really need new 10 degree locks? whats wrong with my old 7 degree ones ?

heads will go on the old 170k kms shortblock, with stock internals and the car will make around 300rwhp.

also, how high can i rev the engine.

E cam, 1.72RRs, gt-40 heads and pistons were flycut already, also the head will be shaved a bit to increase comp. new double spring will be used more likely.

thanks
- Kons

 

[RIO5.0]

Seems like overkill to me...that motor wont be revving high enuf to warrant the valve/lock switch....we're basically talking a GT40 motor..it not like you'll be shifting at 7500... With that set-up i'd stay around the 5800-6000K area...stock internals and all..
most Nascar/Top fuel, those type get into the 10deg set-up from what I read, way high RPM/stress levels...sounds like money wasted to me???

 

[mo_dingo]

But with the e-cam, you probably wont be making enough power to go that high. I think your shift point will be at 5500 at max.
Scott

 

[Joes95GT]

I agree with Andy - they are overkill, but at the same time, they're extra insurance. I'm assuming that they needed to be replaced by the way you worded your sentence. If so, the difference between the two ("stock replacement" and "heavy duty 10-degree") set of valve locks is less than 20 bucks. For just a few extra bucks, I don't see the reason to not do it if the opportunity is there....

Joe

 

[CopMagnet5oh]

sorry, i do not need to change them, but thought of upgrading. thanks for replies. i'll pass on these for now to save some money

- Kons