Hi all, am quite happy to find finally a web site related to the boat performance... My name is Sonny and am from Quebec city in Canada...

Here is the set-up, my boat is a VIP Vindicator 24' 1996, it's my first boat that I have since now 2 year, I bought that boat in part and I slowly rebuild it 2 year ago, I start to run it with a stock 454 MAG carb, with a Bravo one, When I get the boat, the rear transholm was damage so I had to re-cap the aft then re-do a cutout so in the mean time I increase the height or the outdrive of 2 1/2 inche to get better speed. The set up was running OK for me and I hit 66mph on GPS and I was happy with that. Unfortunately last summer during a nice day, I blew it on the St-Laurence River... What a fun story, when I start to look to rebuild it, I start to empty the oil and I drop about 5 gallon of water mixed with oil from the oil pan so I didn't went deeper in the rebuilding story...

So I start to look to find another engine to replace it, I finally found some thing, I found a 502 stroker 560 big block GM, the engine was build for a guys and he finally try to put in a 21' boat and he finally get scared and he remove back for a stock one. The engine actually have Crower crank, carillo rods, high compression pistons, dart head, dart intake, holley 1150 CFM carb, the engine is full roller mechanic with complete crane cam valve adjustement kit, GILL oil cooler and also bigger oil filter, 12 liter oil pan full aluminum pulley kit and lot more. The exhaust system is a full Stelling double wall headers. Basically the engine pulled around 600HP on the dyno which is not bad.

My first trial was not bad, I found some issue as usual like the acceleration pump diaphram was crack an start to leak, but nothing major. Now my major issue is the cooling. The existing set up on my 454 was a sea water system but the engine had is factory pump up front which was creating a close circulation. Now that engine is not running with that anymore, there is a cross over pipe up front with a hose from that cross over pipe directly from the sea water pump and another 3/4 hose go up to the thermostat housing. On the thermostat housing there also two hose also goes down to the headers for the water outlet. The major issue is that I cannot keep the cooling stable at all the engine cannot keep the heat, I disable the thermostat housing the there is a stainless thermostat now but there is 4 times 1/4 inch hole hand drilled to allow flow thru it. Now I suspect the problem is there, on the same time if I use a normal thermostat, am scared the water wont reach it due to the non-closed circulation pump. The other issue is I also blew the 2 first front spark plug, I expect because these 2 front cylinder cannot get hot an off so it's burn spark plug, I would like to know...

My question now is there any special thermostat for this crossover system?? I expect that there is a small hole at least to create some kind of circulation but not an off to create my temperature issue, i alao talk with a local dealer and it's too modded for him so...

Thanks a lot in advance!!!

Sonny

Welcome to the site Sonny. I have the same set up with the crossover. I put in a 143 degree thermostat that I drilled 3 3/16" holes in to allow some water to go through to keep cooling water going to the headers. My temp guage is rock solid at 145 degrees. I wonder if you have a bad thermostat?

Start with a new 140* tstat and drill 3 3/16 holes and go from there. Crossovers can be trial and error to get them just right. More importantly is how is your oil temp?????

Thanks a lot for your answer, I may consider that I may have a bad thermostat, this spring I will change it for a new one, I will try to drill these 3/16 holes. First I was consider to re-install the existing engine pump to keep the cooling in close loop but seem that there a lot of people run with this cross over system and it seem to run OK.

Sonny

This is also a very good question that you bring up, the oil cooling system now seem to be not ok to me. The existing set-up for the oil cooling now use this big Gill oil cooler but also there is 2 other cooler one in the top half of the engine and one below the driver side for cool the power steering as well the engine. To me it's too much I guess, and also the oil have some trouble to heat... I have to verify to see if there any tstat for the oil some where on the engine. I expect to keep just the Gill oil cooler and remove the two other one and use a power steering oil cooler separate. This Gill one is really big and bolt on direct to the block where is the original filter...

I know the set-up is not right for now and all the input will be very appreciate to make that thing runing better, I think am on the good way now. Also I work all time out of my home so the time that I get also is short to work on... Thanks for your help!

Sonny