Push a TIII head...

[2.216vturbo]

Quote:

Originally Posted by mopar2ya I posted earlier that the HG on the R/T finally let loose after about 5 years and being reused. For about a year Ive been thinking about something Id like to try if I had to pull the head for any reason. So Im in the process of sticking some modified R/T intake valves on the exaust side to see if the exhaust flow can be raised and by how much. The intake responds fairly well to being ported, but the exhaust just doesnt come around as well. The small valves and poor port configuration just make it difficult to keep a good intake to exhaust ratio. I'll post what I find when Im done.

Back in '89 when the FIRST motor was apart on my GLHS, the shop I worked for had the same idea, to cram the biggest exhaust valve in the head physically possible. So we did The stock intake is 1.595 (IIRC) adn we found a valve that had the right sized stem and head for what we wanted, we just had to cut the length as it was about 2" too long It was the intake valve from a Caterpillar diesel motor. We thoerized that since it was from a Diesel, it could handle the increases temps of going from being an intake valve to an exhaust valve. That valve had a head diameter or 1.575 so intake and exhaust were nearly the same size! It looked goofy and these were back in the days before we knew shite about big IC's or turbos but the efficientcy of the motor went way up combined with the porting of the head and manifolds. Heck I even lightened the factory LW rods by grinding/polishing the ribs off of the beams. Got like 35 grams off each (BTW one of those rods did eventually let go windowing the original block of my GLHS in '91)

So I am a big believer on doing the majority of the flow/headwork on the exhaust side to empty the motor, you can always cram/overfill the intake side with boost.

Wallace, are you looking at a valve that can handle the increased temps of exhaust duty?

Alan

[cj011]

The old vw sand guys use to do that to there heads. It would end up being 40x40 valves. The heads ran rediculously cool and were super effiecient.

[yogurtslinger]

bigger exhaust valves?? Great, more work for Wallace to do to my head... I would like to beat bring up the cfm a bit, it would be pretty nice having a head capable of 8 sec runs...... )

[mopar2ya]

Im hoping the intake valve will handle it. I cant find any info that the intake/exhaust valves use different alloys for OEM. I know the intake isnt the optimal shape, but WTH.

Bryan your head flows just peachy. It flowed within 9 cfm of SMPs head on the intake and you have stock valves...Thats alot more than My R/T had, which was umm stock flow when I pulled it off. Its only mildly ported now, in fact I swapped the Omni head onto the R/T and am reworking the R/T head to go on to the Omni this winter....Just gotta swap in the Omni trans to make room for the auto...