Your Cadillac is awesome by the way! I've got a customers 57 De ville Coupe here that we'll have on the table soon and I've been sending your photos his way for ideas! And the bed liner is nice for cars like this 4 door. I really don't want to put too much work into it since it'll never be worth anything. The ongoing joke around here is that when we want to sell it we'll pull the body off and get more money for the frame by itself.
It looks to me that the Cadillac has a bit more room under the hood compared to a TriFive. I don't have that all scanned into the computer so I can't quote exact number unfortunately.
I've never experienced any noticeable lag VS tire spin with the STS cars I've been in or built so I can't comment there but I would guess that the turbos were not sized right or the exhaust tubing was too big. I drop the exhaust tubing one size to help raise the velocity of the gas to the turbine as well. It also saving money, weight and time on the installation. For the remote turbo systems they offer sealed turbos now so no more oiling pumps or lines so we don't even have to worry about that weight or leaks any longer. 50lbs that far forward and that high makes a huge difference on the roll center and CG of the car. Just imagine that much weigh with that much leverage over your suspensions roll center as you turn into a corner causing pushing on the front suspension.
The return tubing on my PT-57 truck was all aluminum and was less than 15 lbs total when the truck was done after I removed the inter coolers. I removed the inter coolers from that system because all the aluminum tubing made them redundant. I have this picture but I can't find the written weight. You can see its on a scale and its ticking my off that I can't find that number. All this weighted coming out from the front of the car but I want to say it was 20-25 lbs. And that's off the extreme end of the noise from the truck.
When I had the truck on the dyno the dyno registered 72F as native air temp and my IAT sensor at 6 psi was 75F. We had leaks I didn't have time to hunt down and a really really foul spark map that we couldn't correct I found out later what that was. We used hand held Pyrometers all over the system showed only 5F of heat drop across the IC when it was on the dyno so the only air was from the fan right on the IC not even air flow across the chassis that would cool it even further.
If I was running a built motor or hard core racing I would probably run front mount turbos as well.
Later
-Russell