udlose94z28

bought these specifically for the lt1 alum. head but heard they may be unhardened? To check before install? How do you go about this?

Id rather buy something right now rather than to go back into it while its in the car and the intake is on and reset the rockers

Any advice is appreciated

bombebomb

I am, I was also warned. I only have 200 miles on my engine so my input means next to nothing. But I heard the same thing so keep an eye on them.

97pontta

A simple way of checking if they are hard is to use a file on them. Try to file on a spot where it won't effect the guide plate. If the file "sings" which means it just rubs or may scratch the plate a little, the plate is hard. If the file cuts into the guide plate it isn't hard. This will not tell you how hard the plate is just give you an idea if its been hardened.

shoebox

Check them with a file as already mentioned. In the past, people reported that some of the plates were mistakenly unhardened.

An alternate would be the Trickflow Part # 30400623-8.

jer4251

Ive got the gm guideplates. about 4k miles on them sofar with no issues. gm 847, hardened pushrods and 918 springs, pro mag 1.6 rr's

RamAir95TA

I used the GM plates for about 1000 miles, then switched to the Trickflow hardened plates. Didn't have any abnormal wear on the GM plates when I switched them out.

madhatter

The GM plates were used for years before the Trick Flow ones came out. I wouldn't worry about them.

truedualws6

Just check the GMPP guideplates first. I've had one sent that was not hardened
and a second set that was. I'm using the Trickflow guideplates now.

Bersaglieri

I had problems with my GM ones, I went with ISKY adjustables with my cam swap and they are working great.

-Dustin-