What complications do you guys see with running a TPI setup and stock electronics (1227730) with a reverse rotation engine? Do you suppose it would bolt on (including distributor) and run with no modifications? This is a boat application using two 350ci engines.

 

TPI is batch fire (each bank is fuel pulsed at the same time) as opposed to indivudial cylinders being pulsed, so the FI should work fine. I'm not so sure about the distributor, the centrifugal advance will certainly not work, resulting in a mismatch to your ignition curves between the engines. I am fairly sure you can use any electronic ignition for them, and I'm sure someone makes something for the SBC to run reverse rotation for boats.

Good luck

 

The FI system won't know the difference and the electronics in the distributor don't know which way the distributor is turning. So I beleive that should work.

However, I beleive that the helix on the cam/distributor gear is cut in the opposite direction on a reverse rotation engine. There's probably several resons for doing so, but the main one I can think of is to make sure the oil pump still turns the same direction and pumps oil even though the engine is spinning backwards.

IF that turns out the be the case then you should just be able to replace the distributor gear on the bottom of your stock TPI distributor with a reverse-rotation gear and drop it in as normal from there.

I'm probably forgetting something here. It's an interesting application. I'm going to think about it some more and post back if I think of anything else.

 

batch fire is firing all 8 injectors at once, bank to bank is side to side and sequential is individuly

 

Thanks guys, I'm still watching this thread.

 

The fuel side won't know the difference. The distributor does spin the other way on an RR engine. The mag sensor won't know the difference though. I would look into the distributor gear situation. I think that the cam does have a gear cut the opposite direction, but a simple gear swap should rectify this problem. The cam is totally different in terms of opening and closing events.

It should work just fine and give you more low end torque than a carb, which is just what a boat needs to get up on a plane. Or you could change the prop pitch and get a little more top end out of it.

 

the TPI will work fine.

the only things i can think of are:

• you need a later style EFI alternator.. to "convert" it, it would have to have a reverse cut distrib gear... this is assuming the cams gear is cut in reverse too.
• the oil pump would be spinning backwards. you would need to get a "special" reverse pump

thats all i can think of.
the hall effect sensor in the distrib uses the movement, and isnt dependent on direction.


im sure all the parts needed already exist in the boating world... i never looked into it though. all my motors spin the "normal" way.

 

Yes, definately make sure that the oil pump is spinning the right way. It's easy to check pump operation. Determine which way the distributor will turn in operation, then prime the pump with a drill and a primer (a gutted old distributor can be made to work too). After about 30 seconds of spinning you should have oil flowing freely at the rockers. If you don't try spinning the pump the other way. I'm thinking that this is already a boat motor that you are just converting to EFI, so I think you should be fine with the pump that's already in the engine.

Years ago I built a pair of BBCs for our boat. They were 468s based on LS6 engines. Big solid cams, 10.5:1 compression, single plan intakes, and 850 Holleys helped push 600 HP out of each one. The pair made our 29' Scarab a 90+ MPH boat. Those were the good old days...

 

What kind of boat is it? Sounds hot.

 

I'm not exactly sure what kind of boat it is. He came by to look at my 89 TPI engine on the test stand. Looks like the thermostat housing will be the biggest problem. He was saying there might not be enough room. It'll require more research.

I appreciate the throughts about the reverse rotation engine.

 

Use the stock water neck and build up a hose to go wherever it needs to be. Make sure that the fill cap is the highest point in the system. You can use a remote one if need be and mount it up high. A boat engine should jsut use a stock style t-stat, but instead of a radiator they run a heat exchanger system built into the exhaust (if it's got wet exhaust).

 

My dads old 1960 Correct craft ski boat has a water pickup on the hull. It just picks up the water, runs it through the block, then dumps it into the exhuast pipes and out it goes. Tis a sweet boat. I miss it terribly. She's been out of the water for serveral years due to the wooden hull finally dry rotting. Needs some resto work on the wood. Engine runs great though, we rebuilt that when I was 10 or so.

 

Those older systems can have their downsides, particularly if you run your boat in salty or brackish water. The better systems run a closed cooling system for the engine using conventional antifreeze. The engine coolant is routed through a water/water heat exchanger. The cooler water from outside the boat is used to carry away the heat from the engine. It's the same principle as a car's radiator, which exchanges heat from the coolant into the outside air. The engine uses a pump to force the outside water through the heat exchanger. The impellers in these pumps can become damaged from debris getting sucked up by the pump. When I was about 12 my Dad taught me how to change the impellers in our Scarab. We ran the boat out of a marina with a fairly shallow channel, even at high tide. This meant that those impellers frequently required replacement. I got to where I could change them in 30 minutes. We had a lot of good times in that boat.

 

LMAO!!!!

did anyone not catch that?! i ment distributor, but i typed alternator............ anyone? buler? buler?

 

LOL, well, he's got the right front accessories anyway. It's a conversion from carb to EFI.