Finished Engine Replacement... tips inside
Oil Pan from FBody has to be used
The coolant temp sensor in the drivers side head is a complete different thread size. The 98's are 3 pronged sensors that are I think 1/2" thick, and the one from the 2001 vette was I believe a 3/8"s, and was only 2 pronged. So what I did, was I went to the plumbing section of the local hardware store and bought a reducer, along with a connecting "nipple." Now, the nipple is just a long brass piece of thread, but the thread is plumbing thread, so you have to get a dye/grind set with a 12 x 1.5 to break it down that low. The nipple ended up being too big, and after we would cut it, it would have gone straight through to the hollow nipple, so we found some compressor fittings that worked perfectly for the grind.
The crank pully from the vette is really offset from the fbody ls1. It is a total pain in the *** to get a puller on them for the swap. To put the new one (fbody) on the block, you basically have to nail the **** out of it with a rubber mallet.
Heads on the 98s are completely differnt than the other model years. They have a center bolt pattern, as compared to the more modern perimeter bolt pattern, so you can't interchange the heads at all to my knowledge. Make sure to use teh JMX head/cam install page on LS1HowTo to get the torque of the heads right.
The valvecovers are completely different, because the heads are completely different. This means you can't really mount the coil packs to the new ones, because it has a different bolt pattern. So, I ended up using zipties all around to AIR hoses, PCV hoses, and I think I might have done a couple to the fuel rail (don't quite remember). Just find a spot to do it with... Not hard.
Overall, I would say taking the engine out the bottom is the easiest. Be sure to bring the tranny with it, as it is a lot easier. One more thing, after all that jolting around, CHECK the torque converter, as mine apparently came loose and now I have no power to the tranny because the TC has to be seated correctly in order for it to engage the tranny pump. The transmission works by hydraulics (no mechanical connection between the engine and tranny), the pump HAS to be engaged. Anyway, overall it was successful and took a couple days of hard work in the Texas sun. If anyone has any questions on engine removal, please don't hesitate to ask. Goodluck!



