38 (377) staggered scarab setup (x dimension)
 

I have recently purchased a staggered 377 scarab and am re rigging it with 540 ci Big blocks. Before i install the engines i am cleaning up the transom and was wondering if anyone has ever raised the TRS drives , how far, and what the results were? I will be keeping the TRS drives as i have plenty of parts to keep them alive for time to come. Any help , hints or suggextions in X dimension for a trs on this hull would be of great help.

I know TRS run deep and they'd have to come way up to turn it into a surfacing drive. I forgot the reason this is discouraged, maybe because it was so deep. Try this in the scarab or the classic offshore topic, there are people there who know a lot about this.

konrads will raise the x dimension

Any amount you can go up will likely help and if you are starting with a clean transom and stringers the only real conflict you have is rub rail interference and engine hatch clearance. I doubt you could get them too high. Find out how high you can go and back your way into where they would put the shaft.

To raise X with TRS the engine gets raised up 4" and exhaust holes 4". Bad idea to raise center of gravity on hull with motors higher. That's why Merc designed speedmaster, a number 4 is like four inches shorter to keep engines lower in hull. Put Konrads on her and save a ton of money. I did, im happy.

Konrads would be ideal but unfortunately theyre not in the budget at the moment. As far as fiberglass and wood work I have done this on multiple boats (stringer and transom replacement) and have all the tools, supplies and skills that i need so it wont break my bank to do a little extra work. I understand your concern about changing the center of gravity but didnt plan on going more than 2". I was just curious if anyone has ever done this on this specific hull with staggered engines and what there experience and results were.

most of the time trs drives were mounted deep because back then prop selection was limited.... IMO.... TRS weak link is the lower ..... but a couple of inches up will probably only help the boat

I agree, I know it will definitely help but was curious how much. Ive heard some say 5-6 mph but havent had any hard definite answers. The TRS lower is definitely the weak link, especially the RH rotation. We have had good luck with them just keeping up on oil changes and checking tolerances regularly. We have a 31 Excalibur with twin 700hp blower motors with the drives raised 1 inch and havent had a problem and we drive it like its stolen haha

2" up is not that bad. Your prop shaft center currently must be deeper than 6". Standard depth.
yours is staggered like my Bertram, mine was 6.25" below, with Konrads roughly 4.25" below. I gain 4 mph just with bolting on the Konrads. Still too deap to surface props but better. Then I put 650 HP per side and gained another 12 mph. 84 mph now baby. Turn her up to 750 HP per and I'm around 87-88.
Good luck brother.