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TR4/4A Moss TR2-4A Supercharger Kits

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Tabcon

Tabcon

Jedi Warrior
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Sorry if this is a big repeat, but I could only find one similar thread and it seems to have died...how sad. So now for something entirely different:

How about this Moss supercharger kit?
Has anyone installed this kit?

It's not that I doubt the claims Moss makes on it's website, it's the PRICE!

!!!! TODAY ONLY...TRIUMPH PARTS AT FERRARI PRICES !!!!

Toss in a new high port cylinder head at $3K and you're already in for well over $7K!

Given the selling price for a nice TR4 these days, that's about half the cost of an entire car.

Voodoo economics?

:nopity:

You tell me.
 
I have not installed it, but I am considering it. While I wish it was cheaper, I don't think the price is out of line. The supercharger itself is probably at least a thousand. Add in the custom manifold, modified carb, mounting plate for the belts, pulleys, alternator and water pump, plus the cost of development for what is going to certainly be low-run item and it adds up fast.

I also don't think there is really any other option to increase power and torque that much in a streetable way.
 
Tabcon said:
!!!! TODAY ONLY...TRIUMPH PARTS AT FERRARI PRICES !!!!
Click to expand...

Same old story, if you can't stand the heat, stay out of the kitchen !

Moss did some market research before developing the kit; apparently they decided the market was fairly small and so they need to recover their development costs over a small number of units. I don't know what those costs were, but since it's been quite a few years since they were researching the market, I would guess that there are quite a few man-years of NRE involved.

They even showed a prototype at last year's TRfest (as I recall), and were still doing some last-minute preparation just a few days before this year's TRfest. (Something about not enough fuel delivery at high rpm, due to wrong float valve installed in the carb.) Point being, they put a lot of work (aka money) into this product.

And they are a business, after all. If they consistently lose money, then pretty soon they will be out of business and not selling anything at all. Since no one is forced to buy their supercharger kit, I feel this way is better.

As Ken Gillanders says, "Speed costs money. How fast do you want to go?"
 
It'll be spring before I have anything to report. But the installation instructions make pleasant bedtime reading.

Personally, I'm delighted that Moss sponsored this project. It's astonishing to me to be able to find not just a plethora of replacement parts but extraordinary innovations made available for my fifty-year-old car. I have the same response to Mad Marx's rear engine seal or "Uncle Jack's" front spindle sets or Joe Alexander's steering link pins or TRF's myriad "kits," generally far superior to original parts. I'd certainly put Revington at the top of the list, if I could only figure how to use their web site.
 
@tabcon

Aren't Webers not good enough?

Cheers
Chris
 
Well Chris, as soon as I put a body on it and drive it I will let you know! :yesnod: By the way, how fast is too fast? :banana:

I suppose that if you have a rebuilt and slightly upgraded engine, the supercharger is not that bad of a deal. If it really adds 40 or more horses to a stock engine, then the cost is pretty much in line. In my case though, with more than $10K already invested in the motor, it makes it a bit pricey.

I'm hoping my engine turns around 165 hp and with the addition of a supercharger, maybe 225 to 250 hp. I must admit that I'm very curious and very tempted but I will wait until the verdict is in with what I already have.

0 to 60 Calculator

If this thing is even remotely accurate, it means that my car would do zero to sixty in 3.98 seconds! I realize there are many more variables involved, but what a hoot to even get close to this number in a TR4!
 
Like all things engine wise, there is more involved than just bolting it on. If your compression ratio is too high then it will affect the tuning and the set up will be different than what Moss has set it up for and may find your self going through a lot of head gaskets getting it all sorted. If your lucky, it would only be headgaskets that were blowing. If you have a high lift camshaft you could actually produce less horsepower as well. A mild profile cam like stock will produce more power with a supercharger than a performance cam will.

Generally you can build an engine for naturally aspirated performance or for forced induction performance but not both. Trying to add forced induction to a naturally aspirated performance engine typically ends in a hand grenade. The Moss kit is geared torwards adding that level of horsepower to a stock engine. Not to one that is already modified.

If you want to add another expensive part though, look into the alloy heads they were making in England.
 
LBCs_since_1988 said:
It's too bad that they jacked the price up a good $500 from last week!!! :nonod:
Click to expand...

Yikes, I hadn't noticed that until today!

One Moss reseller is still showing it at $3320.25 with their discount, I wonder if they will honor that price?
 
I would hope that anyone considering "bolt-on" power did a proper job when building the basic engine, especially balancing. When I was in high school, we would hang out at Judson's shop which was close to our home. Judson superchargers were often bolted on in the rear parking lot. Owners eager to test their new rockets would disappear down the lane. We used to bet on which owners would blow up their engines- and many of them did!
 
Tab, I really doubt the stock crank will take that kind of power. You're also going to need to strap the center main bearing cap.

Tab,

I saw your post on Kastner's forum about welding the cylinder head while making my weekly rounds on the forums. I don't have a contact, but ask over on speedtalk.com. A lot of the professional US cylinder head porters lurk over there, and will give you contacts for a few shops that do that kind of work.
 
I still don't see the stock crank lasting that long with power levels over 180bhp.

I also predict that he is also going to have to run different bearing clearances as well.

Keep this in mind, the SCCA National racers in the 1960s had to replace their stock cranks after 5 races. This is when the parts where brand new and power levels where about 155-160bhp. Granted they didn't have access to nitriding either and were spinning them past 6000rpm.
 
Tabcon said:
!!!! TODAY ONLY...TRIUMPH PARTS AT FERRARI PRICES !!!!

Toss in a new high port cylinder head at $3K and you're already in for well over $7K!
Click to expand...

Your joking, right? $7K for a supercharger and a cylinder head, Ferrari Prices? That's not even Jaguar prices. I'm sure GBRandy would be doing hand stands if he could get parts for his Ferrari that cheap. Heck, an ECU for his Ferrari costs over $3K, just a stock cylinder head (just one not the two) cost over $10,000!
 
Anyway, to throw some real numbers out there, from the graph Moss has posted, they report:

regular kit: 120 HP, 142 ft-lbs torque (measured at the wheels)
big boost kit: 134 HP, 153 ft-lbs torque (at the wheels)

Using a factor of 0.8 to estimate flywheel numbers gets:

regular kit: 150 HP, 178 ft-lbs (estimated at flywheel)
big boost kit: 168 HP, 191 ft-lbs (estimated at flywheel)

Their testing was on a 62 TR3 (I assume a TR3A). Unfortunately they didn't publish any baseline measurements before adding the supercharger.

I found one reference that lists the TR3A as 101 HP, 127 ft-lbs of torque (at the flywheel). I believe at that time, these numbers were probably taken under ideal circumstances (perhaps even without accessories like the water pump, fan and generator connected). But even taking them at face value, the regular kit looks to be about a 50HP and 50 ft-lbs torque gain, and the big boost kit over 65HP and 64 ft-lbs of torque gain.
 
The Moss site says about a 40% increase in power with the standard kit, which is very consistent with all the Eaton blowers I've seen (including the one on my Miata), when running at about 6psi of boost. That should give you a solid 140HP at the crank. The big boost kit runs up 2-3 psi more generally, but with it, comes more concerns, specifically detonation.

The biggest problem I see here, is with spark timing control. When I put the supercharger on my Miata, I had to set the timing back six degrees from normal to keep detonation at bay when in boost. It makes for a sluggish engine when not in boost. I quickly purchased a timing controller that retained the basic timing, and adjusted it according to boost, rpm, and other factors. A world of difference. The car is a blast to drive.

I like the idea that Moss is doing this, and the Eaton system is far superior to the old Judson. But, I think that the right way to do this is to EFI the engine with a proper ECU and then stuff on the blower. I'm going to start saving my money! :cheers:
 
I was seriously looking to buy the Moss kit. But then the unemployment man came calling. So for the time being I will wait. All the numbers about how much horse power gain and torque are all great information. As stated earlier each engine is built some what different, results may vary. A little horsepower gain is always welcome. But I just love the way it looks! SO COOOOL!! My 2 cents worth.
 
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