I'm hoping to widen the much needed power band, so I've been spending a few hours porting and reshaping the ports. This car always blew a buff of smoke at start up, and I had thought that at some point under boost the guide seals got pushed off the guides. I've seen this happen before with boosted engines, with stock style seals. Went in to replace the seals and found out that the intake seals are in perfect shape, while replacing them with the newer style seal, I stumbled to what I think was the problem. It appears that Callaway made some changes with regards to the valve guides. (they don't look stock)The exhaust guides are about .125" taller than the intake guides. This was causing the bottom of the retainer to hit the seal on the exhaust side, and pretty much destroyed all the exhaust seals. I'm going to have to grind down some clearance on the retainer in order to keep them from making contact with the seals. I could just imagine what would have happened if 1.6 rockers had been installed without checking for clearances. I don't know if it's like this with all Callaway heads, but for those out there reading this, just as a percaution, before changing rocker ratios, I would check the clearances first. Normally, on a stock cam corvette heads, there is enough clearances when swapping to the 1.6 rockers.
Can't wait to take it out on the Texas "track" in a few weeks - plane ticket came in the mail today :cool
Sam: Good luck and keep us posted! Ike
