HarleyTechTalk

As these come from s&s @ 10.2:1 what cc pistons are used? Is it a .030" head gasket? Chamber volume of the heads? How are they achieving 10.2:1 in other words?

Thanks

IIRC, they use the 91cc SuperStock heads with -10cc (dish) pistons and a .040" HG.

Has anyone ever done a simple cam swap in one of these. At 10.2:1 theres gotta be an RV cam that could pump a big tq number without stuffing it up? I run a 117 with an s&s 570 at 10.2 and it's a nice tractor motor... maybe a TR625??? It's got a Bassani 2-1 on it now but it's that little shorty muffler that muffler could be replaced for the big one. SE58mm w/ 5.3's.

The only simple cam swap you can do in an S&S T series crate motor is with S&S cams made for the crate motor.

If it were me, I'd increase compression to 11.3:1 and run the S&S-625GP cams.

S&S T Series cam chest parts.

Flat top pistons and skin the heads by 2cc and you get 11.3:1.

Is this because they are ez start gear drive? Or is there more to it?

Quote from: Ohio HD
link=msg=1446365 date=1693699362The only simple cam swap you can do in an S&S T series crate motor is with S&S cams made for the crate motor.

If it were me, I'd increase compression to 11.3:1 and run the S&S-625GP cams.

Also I just checked the price book, S&S only supplies these four cams for the T series motors. These also are easy start cams.

585GPE
635GPE
640GPE
675GPE

Here are the 635 specs.

Quote from: 838 on September 02, 2023, 08:59:07 PMIs this because they are ez start gear drive? Or is there more to it?

S&S Twin Cam motors (T series) have a completely different cam chest. Oil pump, cam plate, cams, gears etc. are all S&S proprietary parts. This was how they got around the HD Twin Cam motor patents.

This is what S&S T-series motor cams look like.

Is this the same with the aftermarket s&s cases as well? Do they only accept these t-series components?

No, they can use HD style parts. You can convert the T-series to HD style cam chest.  $$$$$$

Quote from: Ohio HD on September 02, 2023, 09:12:47 PMS&S Twin Cam motors (T series) have a completely different cam chest. Oil pump, cam plate, cams, gears etc. are all S&S proprietary parts. This was how they got around the HD Twin Cam motor patents.

One caveat!

I think that may depend on what year T-series engine someone has.
I have a faint memory of reading something, either an ad or maybe an email where S&S was now installing their TC3 cam plate and oil pump in the T series instead of their proprietary gear drive oil pump.
They used the cam gears as the oil pump in that system.
In searching for where the heck I seen that.
Never did find the specific disclaimer I was thinking about. May of been on their site at one time.

The 2019 catalog has the standalone proprietary oil pump/cam system sold separately.
Also under the Features and Benefits for the T-series it states the T-series has the

QuoteS&S high flow oil pump and cam cover

The 2020 catalog under the Features and Benefits for the T-series it states the T-series has the

QuoteTC3 Oil Pump and Cam Plate

Their standard set up.
The standalone proprietary  oil pump/cam system isn't listed separately (parts are but not the system).
2021 catalog doesn't even have parts listed anymore.

So my long point is if he's pondering a newly manufactured T-series.
I'm pretty sure he'll have no issues installing anyone's gear drive cams.

Double check me though. 

If they did start using the OEM style parts, a quick peak under the cam cover will tell that. I would imagine that a call to S&S with the motor number might do the trick. I would prefer to look myself to be certain.

Good info Cheech.

Quote from: Ohio HD on September 05, 2023, 07:45:55 AMIf they did start using the OEM style parts, a quick peak under the cam cover will tell that. I would imagine that a call to S&S with the motor number might do the trick. I would prefer to look myself to be certain.

Good info Cheech.

Certainly, I was going to post that disclaimer to call with the serial number if used or if inquiring about a new one to verify. Hence the "double check me."

In the words of Turboprop; "Why don't you just call S&S? Good grief" 

Anyhow that info stood out because that proprietary setup always made me skeptical of those T-series as far as if ever wanting to modify one after a few years.
Then I seen where they were marketing them with the TC3 stuff and though that makes them more attractive.

Yeah I agree. They had always locked you into a few cams for the T series. But even their HC version leaves a lot to be desired, much like the 120r.

You can build a better 124" for the same money as long as you're able to assemble them yourself, and reuse your case, motor covers and heads.

Parts, head work, cylinder work I'm at $10,915.00.
Without case, covers, head cores you would be at $8,215.00

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I would recommend calling S&S and see what they actually have to offer in cams.  Beginning of the season I was doing a cam swap and they did not offer the 640GPE.  I was told they really had nothing left for that set up.

I saw that the 2021 price book only showed a few T series cams. I bet you're right, probably limited or no stock on any. 

I learn something every day, today from cheech and hrdtail78.