OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines What Power Torque is my Power Torque?

Hi lads,

As I continue reading into Power Torque motors, getting my hands on them and reading specs for various Victa mowers that were powered by these engines, it seems they're not all the same.

VS160, VSX160, VE50...what's the difference? Power Torque 2? Some have more power than others but they look pretty much the same.

Differences I've noticed have been plain mufflers or ones with Victa embossed on them, fin arrangement on the heads and block, inlet manifold design/size from the carby to the intake port and the size of the intake tubing that is the snorkel.

The last two I can see affecting power levels. I have a Vantage and a Mulch and Catch (two actually, but one is called "The Hulk" and is a parts machine now) and they don't even sound the same running.

Apart from "nicer" features on the Mulch and Catch (Could actually be a late model Commando) such as bigger wheels, different handlebars, mulching blades and disc, more plastic and larger fuel tank, there isn't any "real" differences I can spot between the two. Except of course, for the snorkel and intake differences.

I've searched both on the forum and on the internet generally for actual specs but not having much luck?

I've also come across different coloured float needles and a red spring in the carby? Are these significant? I read here a red spring has a different weight but without context that means nothing to me.

If you know your Power Torque motors, I'm handing you the floor!


Cheers.

What I have learnt.
The ones with fewer cooler fins on the barrel are Chinese castings or the Chinese Powertorque and the ones made before are earlier Australian cast and have twice as many fins. Engineers must have figured that most heat dissipation occurs in the head and/or is most vital on the head, which is alloy. Less fins means less metal needed in the casting -saves $$ in production costs over time. Victa has always been looking for ways to shave costs and charge the same price for the end product. Why do you think they moved from the G3 to the G4/LM carb? Not because it was an improvement for the end user!
Another glaring difference is the long crankshaft version for the Tornado model.
Later versions had a starter with less surrounding metal, designed to carry a different plastic engine cover. That is what mainly differentiates newer models. A new cover design disguises it as a new engine when it's not, for marketing.

As MF said, pretty much about costs and marketing, base models/deluxe, they even brought out one with a low comp head so they could save on the decomp valve, base model wheels and caps, straight handelbar, the deluxe models got all the good bits. Build the same base motor for 35 years and just fit different plastic bits to freshen it up each year or so you can claim it is a new model. Proof is when you get the base design right, why change it, just give it a facelift
As for the HP, you hear figures of 6HP but in reality it doesn't matter that much because it is the tip speed of the blades that does all the work, this is why the little 125's were so good rev them up and they chewed through all the jungle back yards in Aus. When you talk HP my classic example to prove the 2 stroke point is when the 2 stroke 500 GP bikes were replaced by 4 strokes, they had to double the cc's to 1000cc for the same riders riding the same tracks to achieve the same lap times. This was about the only time we have ever been able to compare apples with apples away from the smoke and mirrors of marketing hype
MF another interesting thing I have found (more smoke and mirror stuff) with the Tornado they used the straight inlet manifold, this then filled up the gap above the carby because the carby was higher, they then raised the plastics covers to give the impression it was a bigger motor, but underneath it is exactly the same

Yes it would be good to know what the power figures are, maybe we could even narrow down the most powerful Victa 2 stroke engine ever built!

One day something might turn up but until then all we know is that the powertorque engine when it was released in the new Victa 1984 brochure had some fine print at the bottom of the page saying that it was "7.5% more powerful than the standard Victa 160cc engine". I'm assuming they mean the previous 160cc full crank engine.

Here's a link to the brochure for the new powertorque engine on these forums:

https://www.outdoorking-forum.com.au/forum/ubbthreads.php/topics/70751/BROCHURE_-_Victa_1983-84_Range.html

But does anyone know how much power the standard Victa 160cc engine had? lol

I hope someone out there might have some more information on the power figures for Victa 2 stroke engines.

Cheers!

I used to notice early Powertorque models had "V40 engine pack" labels acne I think others said V30 engine. It was all marketing jargon and any power difference would have been to do with poppet valve settings and a slightly bigger manifold aperture, but real world performance would have had negligible difference.
Back in the eighties when you had the entry level green steel deck with 7 inch rear wheels with plastic sleeves as the bearings vs the flash looking alloy decked models with V40 engine, you had two very different looking machines which performed the exact same duties just as well as each other but at vastly different price points.

Hello MF and all other contributors,
The key differences between the V30 and V40 engine packs is the size and shape of the transfer ports. The V40 having the larger transfer port and hence producing more power, although i've never noticed the difference in power. To me a 2 stroke is a 2 stroke, one of the best mower engines ever made.

Hi Mystyler,

So there are a few things that have been thrown around here that I'd like to cover to the best of my knowledge.

The specifics of how the V40/VS40/VE40 differ from the V50/VS50/VE50 and V160/VS160/VSX60/VEX60, I cannot 100% confirm. That said, I agree with bigted that you should notice a difference between the transfer port sizes, which you would assume means that those engines are letting more fuel through which in turn produces a larger explosion and more power. That said, if you look on the Victa website right now, you'll find under the residential mowers a VE50 which reports 8 NM of torque, whereas the commercial model reports a torque of 7.8 NM. So not 100% in relation to that, I think the website is probably just wrong lol. However, the other differences that you can clearly see are the snorkel size and muffler.

Moving to some of the internals, there are several versions of the main jet. These different versions will allow a different amount of fuel through them, which can relate to power output as well.

Sticking with the internals, the diaphragm spring, you mentioned the Red spring. The mowers and their governing speed work off vacuum which is created by the flywheel, and the springs. When a mower is running at full speed, the hose at the top of the carby sucks the air out of the diaphragm cap due to a vacuum created by the flywheel (The other side of that hose is connected to the engine block, under which is the flywheel). This, in turn, pulls the poppet valve closed so as to not let too much fuel into the engine. When the engine slows down due to hitting a thick patch of grass, for example, the flywheel slows, reducing vacuum which reduces the vacuum on the diaphragm cap and allows the poppet valve to open, allowing more fuel into the engine which produces more power, which is why the engines speed up after they bog down. The spring installed in the diaphragm cap will change how much of an effect the vacuum has on the poppet valve. If you install a 250G plain spring, it will be stronger and the vacuum will have less of an effect (Resulting in the poppet valve being more open, allowing more fuel in, and running at a higher RPM), than if you installed the Red 150G spring (Which would result in the poppet valve being closed more, reducing the fuel entering the engine and RPM's). The lower the spring number, the softer the spring and the softer the spring, the easier the vacuum can pull the diaphragm and in turn the poppet valve, up. So I would assume the "Weight" of the spring would refer to how much weight it can hold/repel/resist. Make sense?

The Victa Power Torque 2 engine is the result of redesigning the engine to meet new emission standards that were introduced years ago. These engines are denoted by the VE, instead of just V or VS. I can only assume the E stands for Eco or Environmental. These engines were designed to run on 50-1 2-stroke mix I believe, and there were modifications to the spray nozzle, spray nozzle position, carby body, jet, compression, exhaust port positioning, muffler, and engine block, all to try to meet the new standards, which they did successfully. That is of course until the standards were changed again, at which point Victa said.. you know what.. we're owned by Briggs and Stratton now.. why would we re-design a classic at a huge cost to us, when we can just use our existing range of 4 stroke engines which already meet the standard...?

Just a note on the engine fins, as mentioned by Mowerfreak. Yes, the fins are heavier and longer in the newer engines, but this was done to lower engine temperatures as part of the re-design for the VE series.

For the carby needles, I've seen Black, White, Yellow, Orange, and Silver. The difference between all of them, unknown, except the Silver/Metal coloured ones, they have rubber tips to try to seal off the float chamber better.

For the carby float chamber cap and what's inside the fuel inlet port, I too have seen some with a spring looking device and others without, I'm assuming the spring is an older design but I'm not 100% sure.

I hope this helps if anyone knows I was wrong about something please correct me, I'm just going off the information I had available to me and figuring this stuff out over time, I'm not a mower or 2-stroke certified engineer/servicer or anything.

Cheers,

pau13z

Thanks Paul, very interesting.
I really admire the PT engine and have 3 for my personal use.
I have always thought they were Australian designed. Do you know anything about their origin?
I heard the Victa twin was designed in Canada.
thanks
speedy

Hello guys, thank you all very much for your insights. bigted and pau13z, thanks for your mention of the transfer ports. I have a small engine book that lists them as "old" and "new" or something to that effect. I guess if you wanted to create a power differential in what is otherwise essentially the same motor, that would be one way of doing so. Also thanks for the info regarding the red spring. I have one kicking around now, and might use it on an engine that is running too quickly.

Regarding the main jet, I've read that they have a different number of "lines" on them, which indicates fuel flow, but I've never come across them. Not that I've noticed anyway. Is that the correct way to identify them?

I could have also sworn one of the float needles I have come across was pink...who knows what it means! I've got some metal ones with rubber tip on order from ebay.

So I guess a Power Torque is a Power Torque. If you swapped over some simple parts you can essentially get "full" power from the things. I'm also guessing that a PT2 does not share a whole lot of common parts with the other PT motors, reading the above post by pau13z.

The only other difference I've noticed is the crank pin.

I've seen pink or salmon needles, as I call them, yellow black and off white being the most common.
I just assume the colour had to with when they were made or being aftermarket.

Regardless of the colour as soon as I get a mower the plastic needle goes straight in the bin, I don't even attempt to see if they work or not. MF I think it is the black ones that are the shortest, this is why you have to be careful with the one length viton ones, the primer caps vary and on some the float comes up too high and hits the body of the primer cap and won't shut the needle off. I have to visibly check every one up against the light to make sure it works properly. Even a new primer cap and needle with an old float can have the same result. I have to mix and match to get a set that works and even then they can still fail and not always straight away, sometimes a week after fitting a new set they can start spewing fuel out the primer bulb

Hi speedy,

If you are to believe the advertising material (Below), the PowerTorque engine was designed and built in Australia and released somewhere in the mid 80's.

Hi Mystyler,

To identify the jet in use, please see the images below. Note that the rings refer to the raised sections on the face, not the grooves. Based on the parts manual and the figures noted next to them, it's a fair assumption that the purpose of the different jets are to allow different mL/Min flow rates which should relate to additional fuel, power, and RPM.


Some of these parts are interchangeable, however, that doesn't mean the mower will run as designed, or have the emissions that are expected, etc. As I understand it, the current carby replacement available is the same carby that comes on the VE series of engines, which should be backwards compatible with other PowerTorque engines. The question is, what main jet, poppet valve setting, and diaphragm spring, do you use to get the correct settings for the mower in question? The carby replacement I refer to is part number CR03773A.

More information on the creation of the VE series of engines can be found at the Museum of Applied Arts & Sciences - https://ma.as/364560

As I'm aware, there were several revisions of the PowerTorque Engine. You have the original V series (V40/V50), then there was the V160/VS160/VSX160, then there was the VE series (VE40/VE50/VEX60).

I'm sure I'm missing a lot of model numbers here so please, if anyone has additional info, share it.

As I understand it, the VSX160 was the newer more powerful engine which was released, and the modifications which I listed in my post above to the various engine and carby components allowed it to keep or increase the power output while reducing emissions. This is why the name changed from the VSX160 to the VEX60.

The crankpin can be different depending on the chassis and blade setup. Something else I forgot about, depending on the model of the mower and if it's a residential 2-stroke or commercial 2-stroke, is the inlet manifold shape. Higher powered models have a straight manifold, lower powered models have a bent manifold.

Hope this helps

Cheers,

pau13z

The only thing I do not interchange on these carbys is I do not use the black poppets from the G4's, everything else works fine

Hi Normk,

As per the document below, there were changes to the body of the carby. So if you're going from newer to older, you may find the mower more stable (In relation to fuel supply and carby function). However, if you go the other way, and take an older carby and put it on one of the VE series mowers, it might work, but who knows how well, and you may end up having issues down the track. Also, if you're worried about emissions, you may notice a difference there too.

https://www.outdoorking-forum.com.au/forum/u...2220/filename/322-PowerTorque2Engine.pdf

Bit too late for me to start worrying about emissions Paul, I'm more interested in getting the grass cut and with the couple of hundred 2 strokes, PT's and FC's I have got back into service, the emissions created is in total zilch compared to the pollution created by the manufacture of ONE new Chonda mower that will be sent to landfill after a couple of years

And also about the springs, I often just cut the long spring in half and one half below the diaphragm and the other half above it, works fine because I don't use the governor on them, I just use the springs to keep some tension on the diaphragm to open and close the poppet

Interesting to see the next to useless idle adjustment dial on the carby in the Powertorque brochure. I thought they did away with that in 1978 with the introduction of the LM.
I have a FCSP Mustang with that dial.

That is a bit harsh MF I find the G4 cap is fine, no problems to me and it saves me having to fit a 6mm nut as I do in the LM caps so I can adjust the idle

NormK, it actually works the best I've ever seen (heard) with the modified carby. You're right about it saving the trouble of fitting your own. I'd like to find more of them for that reason.
In the event I need to install the nut and bolt, is there any compound involved? It looked that way in one of your pictures, where the bolt goes in.

pau13z, thanks again for the info!

I actually have a table in my book for poppet settings, etc for various PT engine "types". I'll get it scanned and share it here.