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Anyone finished their winter engine builds and ready to test
http://ww.w.hpbc.ca/viewtopic.php?f=20&t=4562		 Page 1 of 2
Author:  Hounddog [ March 28th, 2024, 1:18 pm ]
Post subject:  Anyone finished their winter engine builds and ready to test
I know in the T Boat group there has been a lot of engine building over the winter months. Several are ready to test and it will be interesting to hear the results. I got a rebuild started on a 56 OMC this winter. In the early 1990’s APBA started the SST 70 class. It was originally a mod SST 60 tunnel with a modified 56 OMC motor. Later the class included 1/2 (3 cylinders) of a V6 Mercury and that motor made the 56 OMC not competitive.
I able able to purchase Sam L /Baker Marine mod 56 powerhead in the 1990’s, I thought it might be a good lake runner on a T boat, but the very high exhaust porting wouldn’t work so the engine sat until this winter . Tim Topping pulled the sleeves and installed Stock SST 60 sleeves so it will now work on a T Boat.

Anyone else have a story to share??
Author:  sharpeye Mike [ March 29th, 2024, 8:15 am ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
I've only tore my Vee 4 apart so far.
I want to send it to Monty Racing for a mod 2 but first I have to build a crate that's light but strong. I was thinking of glassing a carboard box. Every pounds count.
Author:  Hounddog [ April 4th, 2024, 2:25 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
sharpeye Mike wrote:
I've only tore my Vee 4 apart so far.
I want to send it to Monty Racing for a mod 2 but first I have to build a crate that's light but strong. I was thinking of glassing a carboard box. Every pounds count.


Something like these!
https://minneapolis.craigslist.org/ank/ ... 76419.html
Author:  Hounddog [ April 4th, 2024, 2:51 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
I hope some T guys try the “Stuffers” on their OMC build!
https://www.ebay.ca/itm/324148394328
Author:  sharpeye Mike [ April 4th, 2024, 5:52 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
Nice
You're the man Don
Mine is a looper and I cut mine down to 15.5"
I've seen the stuffers before but they don't look they would make that much of a difference but I could be wrong
Author:  mercrazy [ April 5th, 2024, 9:23 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
I managed to do some 56 sleeve swaps to what we think is the most efficient block and the most efficient sleeve. To my knowledge this combo never came as a production option but with the talented boaters out there trying different things this seemed like an interesting combo to put together to at least try! Hopefully i will be able to try it out this summer then report back with a win! Or a fail! Lol! I don’t think it will be any worse than what i have already put together in the past but as it sits its around 150psi compression with the usual big carbs.

Has anyone else got any new builds to talk about? I love reading this stuff even if its just something you stumbled across and think it might work!
Author:  LittleCharger [ April 7th, 2024, 8:21 am ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
mercrazy wrote:
I managed to do some 56 sleeve swaps to what we think is the most efficient block and the most efficient sleeve. To my knowledge this combo never came as a production option but with the talented boaters out there trying different things this seemed like an interesting combo to put together to at least try! Hopefully i will be able to try it out this summer then report back with a win! Or a fail! Lol! I don’t think it will be any worse than what i have already put together in the past but as it sits its around 150psi compression with the usual big carbs.

Has anyone else got any new builds to talk about? I love reading this stuff even if its just something you stumbled across and think it might work!


Tim,

What did you throw together?
Author:  Hounddog [ April 7th, 2024, 11:48 am ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
[quote="mercrazy" Has anyone else got any new builds to talk about![/quote]
Thanks to Tim and Paul Hickey I have a new 56 build completed over the winter.
Here’s the story.
Over 20 years ago after the SST 70 class died I was able to purchase at an APR SUPERLEAGUE Race in the states an OMC 56 SST 70 powerhead. It had been just been refreshed but never started. I thought it would be good as a T Boat lake runner. Paul Hickey and I checked it over and realized the porting was so extreme that it wouldn’t be a very good T Boat motor. Paul had the powerhead until this winter. Tim was doing some sleeve removals on 56 blocks this winter and suggested we change the sleeves. In my garage I had 3 New old stock OMC SST 60 sleeves and 3 New old stock standard bore wiseco pistons. Tim disassembled the powerhead and found assembly grease on the bearings proving the motor had never been started after the refresh. The motor was assembled last week. The compression was 163 psi with it’s current cylinder head. That’s over the legal 160 if the motor was to race so we will get a second cylinder head cut with a .525 depth and that will drop the compression below 160. The motor is a stock SST 60 sleeved 1986-7 block with SST 60 reed cages 73D main jets. Motor will eventually be installed in a Johnson Stinger 15 inch nitro case with a Kevi billet baseplate and tuner.
But first it will run at 6 mile to see how it matches up against the other powerheads.
Author:  LittleCharger [ April 7th, 2024, 12:19 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
Hounddog wrote:
[quote="mercrazy" Has anyone else got any new builds to talk about!

Thanks to Tim and Paul Hickey I have a new 56 build completed over the winter.
Here’s the story.
Over 20 years ago after the SST 70 class died I was able to purchase at an APR SUPERLEAGUE Race in the states an OMC 56 SST 70 powerhead. It had been just been refreshed but never started. I thought it would be good as a T Boat lake runner. Paul Hickey and I checked it over and realized the porting was so extreme that it wouldn’t be a very good T Boat motor. Paul had the powerhead until this winter. Tim was doing some sleeve removals on 56 blocks this winter and suggested we change the sleeves. In my garage I had 3 New old stock OMC SST 60 sleeves and 3 New old stock standard bore wiseco pistons. Tim disassembled the powerhead and found assembly grease on the bearings proving the motor had never been started after the refresh. The motor was assembled last week. The compression was 163 psi with it’s current cylinder head. That’s over the legal 160 if the motor was to race so we will get a second cylinder head cut with a .525 depth and that will drop the compression below 160. The motor is a stock SST 60 sleeved 1986-7 block with SST 60 reed cages 73D main jets. Motor will eventually be installed in a Johnson Stinger 15 inch nitro case with a Kevi billet baseplate and tuner.
But first it will run at 6 mile to see how it matches up against the other powerheads.[/quote]

Did you run the motor and check compression or was that cold?
Author:  Hounddog [ April 7th, 2024, 1:28 pm ]
Post subject:  Re: Anyone finished their winter engine builds and ready to
LittleCharger wrote:
Did you run the motor and check compression or was that cold?


Paul, the compression reading was a cold reading.

Years ago Dave Elsey and I did cold reading comparison cold compression tests on several different 56 cubic inch Bridgeport powerheads including pure SST 60, non rebuilt stock powerheads, rebuilt T850 spec ported and rebuilt stock
Powerheads with several different sized cc cylinder heads. We used two different compression gauges for the testing.

A pure SST 60 with it’s spec SST 60 head was 175 to 180 psi.
The non rebuilt stock 56 with that same SST 60 head was 155 to 161 psi.
The rebuilt stock 56 were 165 if the block was decked during the rebuild.
The rebuilt T850 Spec powerheads were all below 160 psi with the spec SST 60 head.
The pure SST 60 needed approximately a 30 cc head to make 160 compression. We ran that size head on our SST 60 T850.

if the .525 depth head results in a lower than expected reading I know from experience that if I replace the head bolts with studs and re-torque the head with a thinner head gasket I can increase the compression several lbs.
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