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Saw an engine today with an 8cyl on it. Had the GITSU cylinders on it, and the intake was on top. Looked like it had only one mag. The guy said it was a 720.

I didn't really look close at it, but I am confused as to what this engine was.

Could it have been a 720 with Continental cylinders? I've never seen that combo on an 8cyl, but if that's what it was, then it wouldn't have been a 720 would it? :?

According to my calcs, if it was a 626 Cont with 520 cylinders, it would be a 693???
Wow I was just thinking of asking the same type question almost :shock: I know Lycome has a 720 but what is the 8cyl cont engine and any ideas where o find one and some 720 jugs

If you find any info let me know I would be interested as I am trying to plan ahead and I have apparently been convinced I need a little extra hP
I'm not a 100% sure butt it has 520 jugs on it.it has a different stroke on the crank
were the cylinders mounted upside down? ive seen them do that before on gpu cases to put better cylinders on. seen the same with upstack lycoming cylinders on contentals.
If I'm not mistaken Continental did make an eight cylinder ground power and if thats what it was it would have been a 693.

If it was a Lycoming with Continental jugs it would have been a 758. The Contintal has a larger bore than the lycoming. (5.25/5.1250) The Lycoming has a longer stroke

Bore x bore x stroke x .7854 = CID per cylinder.

Either way I don't see how it could have been a 720

Goldhunter_2, All O/IO-360/540/720 Lycoming cylinders are interchangeable as long as you keep in mind that there are narrow deck cylinders (old style engine) and wide deck cylinders (newer style engine) Most airboaters (but not all) use the narrow deck cylinders.

Continental has a 8 cyl gpu, they run pretty good, but seem to be a little heavy. That case was modified for gitsu cylinders probally a good combination. Did you notice what carb it had?
Layla has taken several pictures of one of those for us. Here is one of them:

so a 8 cyl cont case & crank with lycome rods and cont jugs will provide the max output possible then does that sound about right :?:

any ideas where to find one around here?
Rod length does not affect the size or Cubic inches of a motor. I believe the rod length differance is .125 between a Continental and a Lycoming
If it only had one mag, wouldn't it likely be the GPU though?
I have been told several times the 8cyl Continentals are originally GPU's used in fire trucks to power water pumps!
That was one of the uses. I have seen pictures of them in that application. Probably had other apps too.
The 8 cylinder continental is a ground power unit. It had many uses, one I was told it was used to get big turbine engines started. The 8 cylinder continental is a BIG BLOCK and has alot of power. You figure a 520 continental @ 300hp is 50hp per cylinder so 8 cylinders x 50 hp per cylinder is a whopping 400 hp stock. Imagine if you put lycoming rods and lighten and balance the rotating assembly. You go above and beyond 400hp easy.
I will post a couple of pictures if someone will tell me the secret of how to do that on these computers[/code][/list]
Theres a pretty good pic of JCs eight cyl with gear box in my pic gallery,but I dont know how to move it to this thread.Sorry guys

Here ya go skeeter..... Cowboy
Skeeter, you would think an 8 cylinder with a gear box would be the baddest thing on the river. Whats up with the gearbox on the groundpowers, i didnt see any at the races and i have not heard alot about them on the river or seen them out there. Are they all that and a bag of chips or not.


Click on your edit button for this post. You will see what the "Picture Text" looks like.
Then go into the " On the Hill "section of the board. Moodfood posted a great explanation there on how to post pictures. It's simple.
That's probably all the same exact laughs the A/C direct drive crowd had when Auto boats started running PSRU's.

Nowaday's the real autoboats are running torque multiplyers.
New props came into being to help that.
Sweet part is that the A/C motors won't be going through that PSRU development phase.

Here's a picture of a six cylinder with a silly little prop on it.
It truly needed more prop than this I believe.

Checkout your last post above for Picture Posting help.