I have a 455 with late model heads 78cc and i'am buying some 430 heads that are 68cc. I was wanting to know if I shave the heads .040 would it be around 63-64cc? Also will I need to shave the intake? Im using the SPX intake form TA Performance. I also had a valve train promblems with the passenger side head. The pushrod was bent and the valve spring down by its self the passenger side of the motor ran hot and driver side ran cool and the top raditor hose craked by the intake... What happend to cause the valve to be stuck opend???? How do you put the bigger stage 1 valves in 430 heads. I know machine work will be needed, and were would you get new stage 1 valves? Thanks for any info.
Hi Brian. TA Performance and Poston both have Stage1 valves - stainless and stock types. If you shave the heads then you must also shave the intake. A good machine shop should know what the relationship is. Not sure what the final cc would be after you mill them. Also, a good shop should have no problem fitting the Stage1 valves into a 430 head. It is just a matter of opening the valves seats up. But have them magnaflux the heads first because 430 heads have been known to suffer from cracking problems. As for what would make the valve hang open like that??? Not sure. Again, a good shop can look at the head and be able to answer that.
Brian, You may want to price out the changes you would have in mind for the Stage 1 conversion. Also understand that you don't just swap the valves out. The seat area will be need to be unshrouded. This alone won't necessarily show you an improvement over a good set of standard valve heads though. You may need to do a little more head-work such as unshrouding the valves to make it worth your while. By the time you're done, you may find that it would be a better deal to either buy some of the new aluminum heads (I think they're still on sale at TA for BPG members) or find someone who just got aluminum heads and is selling their already worked iron heads. Prices for good iron heads are in the $1000 range lately. Do a search in the parts for sale section with heads as the keyword. You'll see what they're going for.
I asume you will use pushrod oiling method of the 455 to oil you're rockers. If you use 430 heads on a 455 you must plug the hole that feeds the driver's side rockers. You will see it only on the drivers bank on a 455 at the front that leads to you're front cam bearing. That will also give you a little more oil at the front cam bearing, where you need it. Best of luck.
i had the same problem with a 360 fe heads that a valve stuck open. i had taken them to a machine shop to rebuilt and after puuting them on the engine probably 5 minutes later the the valve stuck open.i took it back supposedly they fixed it and again after 5 minutes it stuck open.many people told me the valve guides were too tight but after sending the heads to another shop they found out that the previous shop had put the wrong valves,some of them were a little too long and milled the heads crooked on the intake side. they said they were unrepairable because of that bought some new heads never had a problem after that.so check for correct valves and the guides.
