Why/Why not use crossover
 

I am rebuilding my gen 6 502's that had blowers on them. They also did away with the water circulation pump. They had just a crossover instead. This seems to be a popular setup with blowers but I plan on rebuilding the engines back to the 502MPI setup. My question is should I buy new circulation pumps of go just with a crossover? What would be difference between the two? I mean you already have a seawater pump pushing the water through. Why should I spend the money on a new circ pump? Does it really matter? - Ray

The reasons note to go with a cross over is that you will proably have excessive pressure and the engine will run too cold.

That said, are you interested in selling one of the crossovers?

If you want to sell the other, let me know.

The cross-over will eliminate the HP robbing recirculating pump. Croos-overs are usually located on the supercharged motors. It will allow more cooling. I run a restrictor disc instead of a t-stat. I'll run all day on my SC motor and top out at 160*. I don't see many downfalls with the cross-over. You can run t-stats with these if your water temps remain cool.

I'm not sure if your computer for the MPI will have problems. If your water temps are too low your computer may have you running too rich (start/warm up mode) ???

The crossovers are allready spoken for if I dont use them. - sorry

It will be a EFI setup and I am concerned about the ECU too.

Thanks for the input!

Ive never done it so this is all hearsay. The circ pump take 5 hp. People remove them on blowers due to the pulley and belt problems. If you trailer and basically do start and run full WOT, crossover OK. If you have to idle out of a marina or channel etc. the circ pump will help maintain better control of engine water temps. But I just drank way too much crown so what do I know. I'd rather have circ pump just to help keep the engine temp constant.

.

RandyI have a 502-blower motor with an intercooler. I use a cross over with a bypass a thermostat. This has all the advantages of the circulating pump with out the extra belt. For information I'm going to put a closed cooling system on so the circulating pump is going back on soon, as soon as I get the custom built SEN-DUR heat exchanger mounted. I want a more even engine temp.

Randy

Just installed Stainless Marine's x-over kits last summer on both my 454 mags (stock carbed). I asked the same questions here on the board that you are asking and it seems different people are getting different results. Personally, I didn't see the wisdom in spending $200+ per circ pump when I could clean up the front of the motors and gain some HP (albeit a tiny bit) by buying the x-overs. Anyway, I've had no problems at all with mine, idling or at wot. Does take a little longer to warm up due to the volume of water that is forced into the motor. Run mine with t-stats. Good consistent flow and temp.