mac62989

iTrader: (1)

Are aftermarket rockers a must with AFR's? Looking in my AFR product guide I see no options to upgrade to powdered guides. What are the chances a problem arises with the bronze guides even with a mild camshaft? I know the upgraded springs are always recommended but Im not sure why if your not revving the **** out of the engine or running a cam bigger than .600 lift. I chatted with Tony awhile back via PM and other than the upgraded springs the other things didnt come up. Im just lookin for some opinions/answers from those AFR users. Any problems that ever came up or how many worry free miles on your setups? The ported GM heads vs. AFR is a tough choice. Both have pros and cons, Im just trying to figure out what fits me (and my wallet) best. Im sure Mr. Mamo will chime in as well as he was a great help with my previous questions.

-Matt

mark21742

Brine guides work great, but are softer and will wear quicker than the powdered metal guides when you put a side load on them...that is the reason you are recommended to get the roller tip rockers with the bronze guides. You can use stock rockers with them, but will get side load and premature guide wear

Tainted

iTrader: (9)

^^ in short enjoy wearing out your guides risking destorying something when it fonally lets go, and have fun removing your heads and having to replace the guides.

Get roller rockers, but check all your measurements and make sure everything is right.

RezinTexas

What is your experience with this and how many miles, cam lift, max RPM's etc. did you have on the setup?

vettenuts

iTrader: (4)

I ran Cranes with another type of bronze guide head. The Crane rockers have a rather wide wipe pattern but weren't as bad as stock. I had noticeable wear within 10K miles.

I now run AFR's with YT rockers. The wipe pattern turned out very narrow and centered and were more easily adjusted to get this pattern. I was not able to get this pattern with the stock rockers despite spending a few night trying (I still have my stock rockers preserved in oil). If you are going with the AFR's, spring for the rockers too.

RezinTexas

what valve lift and peak rpm's were you running?

mark21742

I'm running heavily worked 241's with a 255/271 .624/.624 115lsa cam spinning to 8,000 right now...90,000+ miles on the stock valve guides and original rockers have been upgraded with the Truton (sp?) kit. Any time nomatter what the lift is if I had bronze guides I'd run roller rockers

vettenuts

iTrader: (4)

Lift was low, 0.551" on my previous cam. The Crane rockers have the high ratio off the seat ("Quick Lift") when motion starts and the resulting wipe pattern is widened as a result. The stock rockers start at a lower ratio (1.54 as I recall reading) and build to 1.7 at full lift but they also wipe wide on the valve stem. I spent a lot of time trying to get the stockers to provide a good pattern to keep installation simple and the valve train light but I never got there. In contrast, the Yella Terra's set up in a few minutes with some shims and washers to establish a proper height, then I ordered a correct single shim from McMaster-Car for final installation. Several months after I initially installed the Yella Terra's, I removed them for a pushrod change and the wipe pattern could be seen on the valve stems if you held the light at the proper angle, they were narrow as measured on the work bench.

mac62989

iTrader: (1)

Im surprised out of all the guys running 205s only one chimed in. After reviewing all the old threads this is just never mentioned and Mr. Mamo didnt mention it to me either. I get it makes sense to run them but how many people didnt and ran worry free?

vettenuts

iTrader: (4)

I tend to do the worrying up front in hopes of preventing issues down the road. My experience with the prior set of heads lead me to the Yella Terra's on the AFR's, which were a lot more money and I wanted to ensure long life.