vic1989

I'm curious if anyone has had any problems with the PRC ls7 valve guides. I currently have 3500 miles on my PRC heads and they are on the verge of dropping a valve!

C6z06man

What ar ether specs? Wiggle test or actual measurements? What's the mileage on the heads. PRC heads or they did your stock heads?

vic1989

They are their PRC 285cc head.. With roughly 3500 miles.. all I did was a simple hand wiggle test with the springs still on it. I was pretty pissed about it so I didn't take the time tonight an take the spring off to get an actual measurement. But with slight pressure with a screw driver the rocker damn near falls off the valve!...Tomorrow ill get an measurement with a dial indicator.

Brandon619

Vic, I would try contacting PRC or Texas Speed of this issue. I'm pretty sure that they rectify this situation asap.

vic1989

I plan to give them a shout. But I was curious though if any other member on here has had this issue. Not 2 weeks ago there was posts on another forum with two shops saying they have had nothing but issues with the PRC heads and there I was calling their BS and backing Texas speed up.. That was the real reason I figured I would check while I was swapping valve covers. This is something I don't want to happen again nor do I want a valve drop and destroy my built engine!

Vito.A

Can you explain how you performed the test?
A screwdriver against a rocker does not sound correct.

1968swbbigblock

I too am curious how you checked.
A rocker arm will certainly move with the lifter at the bottom of the base circle of the cam.
You are going to drop a valve if your keepers are falling out or if the angle of the valve stem vs guide exceeds specification during the rotation of the cam, which basically turns the stem into a lever against the keepers and exceeds their holding capacity.

old motorhead

I have a set of catty port PRC heads that had the valve guides wear out prematurely. Broke a valve spring at about 20k miles. This was a new motor bought from and assembled by TxSpeed. They offered to replace 1 (that would be one...and only one...the broken one) valve spring or sell me a full set at a reduced rate. Shortly after replacing the valve springs, I ended up pulling the heads due to excessive oil consumption. The machine shop said the valve guides were shot. I bought all new chit thinking I'd have a few miles without issues....stupid me.

Very mild cam too.

vic1989

The night I noticed all I did was wiggle the spring and can tell they were way out of spec. What I meant with the screw driver was that with the rocker still on I can pry (with very little effort) on the head and the spring and almost make the rocker fall of the valve tip. Since then I pulled the heads and with the valve seated I have 0.025 of movement and with the valve opened a little bit the valve jumps up to 0.037. that is in mostly just the intake valves but there are a few exhaust that are that bad. On cylinder 6 there was a broke exhaust spring. Texas speed did say they would take care of all the head repairs free of charge but I'm more concerned if this is going to happen again!

xBoostx

I would send both heads to them and let them take care of it get a repair statement document from them.

I'm sure they want to know if there's any longevity issues going on, is in their best interest.

You may also request a set of Pac springs for replacement.

GeneSch

I had mine boxed up and ready to go to TS and Im glade I sent them to AH. Best of luck to you. Post a video of the play.

old motorhead

I thought that too. After they refused to replace the rest of my valve springs, I knew it was no use trying to get them to fix my heads. I like to support home state companies, but, I can say for sure, that they will be waiting a VERY long time on my next order.