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New guy on the site and have a few questions.
Why are the evinrudes and johnsons used so much and why not mercs.
Why short shafts used more than long shafts. I thought with the long shafts there would be an advantage with trim.

Good to see you made it over George, welcome! There's a bunch of T guys here with tons of info for ya

The old OMCs put out very good horsepower per cubic inch when the made the old triples and twins. As a comparison, you can get a 59ci Merc that puts out 60hp at the propshaft or a get a 56ci OMC that puts out 70hp at the prop. You can remove the heads on an OMC which makes it easier to bump up the compression as well. Short shaft has lower center of gravity making it handle better. We use through transom trim or modify a Yamaha pro50 trim to fit on the triples. Twins had power trim option for the short shaft. I still think someone could really make one of those 59ci go if they wanted to spend the time and money on it.

Kevin

Thanks that info makes a lot of sense.Right now I have a 70 merc long shaft on a voodoo because when I bought the boat it has the 24 inch transom. Later on I installed a jack plate to bring it up to run better. I bought a 1974 70 stinger with a long shaft that I was going to put on it not sure how good these motors are I know they are only 49ci but for now I will try the 70 merc.
Are the short shafts you put on the johnsons gearcaes the same size 4inches.

We use the nitro style gearcase. Same size as the 2 cylinder gearcase but came with different gears. Was available only on the short shaft 75hp. It is 3.5" diameter. SST-60 is almost the same gearcase but has a nose cone.

I ran a 20" on the delta to get started...it worked just fine. 15's look cooler but it wouldn't stop me from racing lol. Everyone does convert the 15's to trim though and the nitro case (like kevi said) and for the most part string steering. If you are interested in racing come out...no matter what you're driving you'll get to do some laps...it will change your life lol.

On your 24 inch transom VooDoo the 49 cubic inch long shaft Mercury will work fine. It is a legal T750 boat and even with mechanical steering it will drive fine. Low to mid 50's is competitive in the class. Your driving will make the difference. Last year Jake's Delta raised the bar above the others. With a new driver in Jake's boat this year, it may take her a few heats to beat you guys. I think your 18 chopper will also do a good job on the race course. You will hear the drivers talk about acceleration and ET more than top speed. That is because oval racing is all about being quick and not about top speed.
It is more like a drag race from pin to pin. Example: if you get from turn one to turn two in 17 seconds and show a top speed of 54 mph and your racing another boat that runs 17.5 seconds and a top speed of 57 mph. Your boat is QUICKER and it will beat the faster top end boat every time. Most lake racers are surprised when they get beat by a boat slower than their boat.
Their beat because the other boat gets to 54 mph faster than their boat. That is also the reason why racers run smaller props. Just like running a 4 speed car in 3 rd gear. The motor spools up faster.
One more thing about your Mercury..IT HAS AN EXCELLENT GEAR CASE which is very easy to drive. The big foot cases are a real challenge in the turns.

Thanks guys Have learned a lot and am going to give it a try. If the ice goes away and I can get it in the water.
Thanks again

One more question.LOL. In the T750 are the 4cyl. 43.8 ci allowed to race in that class.

sorry the 43.8 mercs