Then in October I was taking the car to the other side of the island the stretch its legs a little before the head swap and the power steering went out while going down the highway. I stopped at the nearest opportunity and checked, the belt was still there and I had fluid, and no leaks. After some posts on the Pro-Touring forum didn’t turn up and obvious answers I called Detroit Speed and Engineering, and after some discussion they decided to send me a new power steering pump. That fixed me up and they didn’t charge me a cent—how’s that for standing behind a product they sold me three years prior? Unfortunately I developed a nagging leak in the power steering system while attempting to troubleshoot the problem and wasn’t able to contain it. The leak was pretty minor, so I decided to soldier on with my head swap.
The head swap went pretty smoothly in November of 2007, and having the heads off the car for the first time since I bought it back in 2004 yielded one more surprise—the shortblock was loaded with forged pistons! The pistons are TRW L3026F. They are also 0.030” over, so I actually have a 355 on my hands. I couldn’t find this exact number anywhere on the internet, and Craig over at Ted’s Automotive Machine who looked in some older TRW and Federal Mogul catalogs but didn’t find it either. If anyone has the exact info on these pistons, please let me know. I measured the top of the piston to the deck height at top dead center and had 0.045” on the passenger side and 0.050” on the driver’s side. Because Chevy generally made the small block so that at top dead center the pistons are at 0.025” to 0.020” from the deck, so I suspect these pistons are not stock height but are a little shorter.
The pistons being so far below the deck also makes my compression ratio much lower than I thought it was. With a bore of 4.030” and stroke of 3.48” and the average of 0.047” below the deck at top dead center, I estimated the volume of the top of the piston as 4 cc’s, I’ll need a 0.015” gasket to get to 10:1 compression ratio. Check out this web page for a great compression ratio calculator. Craig hooked me up with the Fel Pro gasket I needed to at least get to 10:1 compression ratio, although I’d like to get closer to 11:1 since I’ll only be burning premium gas in my aluminum-headed Chevy small block.
I took the opportunity while everything was apart to port the cast iron intake manifold according to the guidance of David Vizard in his book “How to Build Horsepower Vol. 2 Carburetors and Intake Manifolds”. It took me two weekends to put everything together because I spent a lot of time cleaning the heads up and porting the manifold and also because I decided to put some ARP head studs on and they leaked although I had used the PTFE based sealant recommended by ARP. So I spent quite a bit of time posting on message boards, calling ARP, and messing with the heads and re-installed the heads twice trying to get them not to leak but finally broke down and put some AlumAseal in the radiator tank. This cleared the leak up.