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MG TD TF 1500 - Supercharger -Eaton, Moss or not a good idea

Considering a modern supercharger addition to my 1952 mg td and would like some input.

Research has been difficult because most threads deal with MGBs or older less modern super chargers. I read the install instructions on Moss and one article on Eaton on Ttypes site.

Facts on car ( if this helps)

1. Ten year old restoration with 500 miles on it.
2. Compression is 125 in all cylinders, idle and running oil pressure is excellent, temp excellent ( new radiator when rebuilt)
3. CAM specs and head ratio unknown. Suspect OEM or real close.
4. MGA rear gear ratio.
5. Standard rockers and tappets.
6. New tune up.
7. Car does leak a drop or two of oil but nothing major for a British car. I have three.

Input requested on:

1. You're experience with these superchargers.
2. Difficulty to tune correctly. I live in a very rural area and do not have access to a lot of fancy equipment.
3. Pro and cons of supercharging a MG TD.
4. Others sources to research.

Thanks

Joe
JWP Policastro

I too fantasize about adding some more oompf to my 52TD to deal with hills and such. Hopefully this thread will create a nice "requirements" list/guide for the minimum state of engine/car tune/status to guide one on how to go about getting to some additional horsepower and the pros/cons, costs, etc to get there. Will watch this thread with interest!
Randy
R Biallas

I have a 1950 TD. When I bought it three and a half years ago it had a Judson supercharger. Last winter I replaced it with a Moss supercharger. I have no problems with my set up but as you know all of our cars have changed differently over the years. I can tell you about my experiences but hesitate to advise since I don't have the expertise.
There will be others that will do that.
Glad to answer any specific questions.
Mort
Mort 50 TD (Mobius)

In addition to Joe's questions, (don't want to hijack his thread though) I assume that a supercharger would out added stress on the engine, so I'd like to know more about whether things like;
Is the "stock" engine specs (Stage 1?) sufficient or does one need to upgrade to higher stage tunings first before adding a supercharge.
Does one need to do the advanced balancing of crank and everything else. (I presume that stuff wouldn't hurt and only make the engine smoother and better anyway.)
Guess asking about what's the "extra" stuff needed to do before jumping into the supercharger route. Or is there more bang for buck to be obtained elsewhere?
R
R Biallas

Mort thanks. I do have a couple of questions.

Can you describe if the car ran better with the modern supercharger

Is the rest of your car stock -- cam, valves, rockers, etc.

Why did you change?

What rear are running?

Would you do it again?

Are you running a standard tranny? 4 speed.

How does it run on the highways, parkways, freeways or what they are called in NJ? I remember the Garden State parkway and the Jersey Thruway?

Joe
JWP Policastro

R Biailas great follow up questions. I too only want to do stock. Not really interested in tearing the engine a part.

Joe
JWP Policastro

As the North American source for the Mirage Garages Eaton blower, I can answer a number of your excellent questions. Most of the superchargers I have sold have gone into basically stock cars, where the owner wanted a bit more power to feel safer on the road. Sometimes they are installed in conjunction with a 4.3 differential swap, and sometimes in addition to a 5-speed conversion. I recommend them both highly - they transform the car, and turn it into a reliable and more-powerful T-type, approaching a Miata. I promise an honest 45% increase in HP at the real wheels (nothing theoretical about that!), and dyno tunes of the cars have shown that it is an accurate figure.

I will not sell a supercharger until I am confident that the blower and car (and owner) are a good match. I ask a series of questions:
1) How long have you owned your car, and when was the engine last rebuilt
2) Who works on the car, and what engine problems have you had in the past few years
3) What are hot oil pressure and temperature at speed?
4) What state of tune is your car now
5) How do you plan to drive the car

I should say that I have indeed declined to sell a blower to the owner of a car I think is sketchy; a supercharger will not improve the condition of an engine!

Your car sounds as if it is in good shape, and would benefit, especially since you already have a 4.3. My only recommendation would be that you put more miles on your engine before you install any supercharger - 2,000 miles should see your engine fully broken in and settled. Tuning the car will be easier, as you have only one carb to adjust, and it stays in tune for a good long time. I do recommend a dyno tune after installation, as as much as 8 or 10 HP can be gained by a careful tune. I also recommend a distributor rebuild by Jeff Schlemmer, as that is another source where HP can be gained.

I know of nobody who regrets installing one of the dozens of blowers we have supplied, and I continue to get e-mails telling me how great it is. My kit comes complete with the highest-quality ARP fasteners, with installation instructions and Joe Curto carb, and (very importantly to me and unlike others on the market) requires NO CUTTING to make the blower fit. I provide my cell phone for questions, and feel that I can help with any installation problems.

Some owner comments are on my webpage (mgtrepair.net), but I just heard from an Australian customer who took his TD on a longish road-trip with his local club. Although his was the only T-type in a field of other cars, his car with my blower had no problem keeping up with the MGB's, and took hills in 4th where before he would be down-shifting constantly. He feels that the torque in the 2000-2500 range is much improved, and he could not be happier!

I will be happy to provide owner's names and contact information (with their OK), in case you wish to address them personally. I am also happy to answer any questions, 207-479-3695 (cell).

Cons are slightly increased fuel use, and some small degree of inevitable engine wear, as you would find with any engine improvement.

Tom Lange
MGT Repair

t lange

I have two supercharged MG TC's..

#1 - Almost box stock. Engine was sleeved back to stock, original crank, rods, new pistons and rings. Cam upgraded to Crane 3/4 race. Valves and valve train stock 1250. Rear end stock (for TC) 5.125, transmission upgraded to Sierra 5-speed so I could get out of my own way in traffic. Marshall-Nordec supercharger, 4-5 lbs boost. Car is comfortable to drive, lots of torque and still reliable. Tuning is easy...ONE carburetor. Pretty much just adjust idle and go.

#2 - Bored 0.80 over, J&E pistons, Saenz rods, billet crank, Len Fanelli roller cam, extractor exhaust, 1500 spec valves and rebuilt valve train, etc. Did have a 4.55 rear end, just changed to 4.22, transmission Sierra 5-speed. Eaton (Moss equivalent) supercharger, 4-5 lbs boost. Again, lots of torque and fun to drive and only ONE carburetor to mess with.

You're not going to gain a lot of top speed, superchargers are good for torque, not so much for speed...you'll notice it most when changing gears. They don't put out a constant boost pressure, only when needed...most of the time you won't know it's there but it's nice to have when you need it. Helps greatly going up hills, very little downshifting needed, so if you live in a hilly area you'll love it.

And did I mention there's only ONE carburetor?
Gene Gillam

Thanks Gene. Yes hills are a issue for me. I drove 140 miles one way to go to a MG T gathering once a month and have never been able to drive the TD. I drive my other foreign cars which I do not like to do to a MG event.

The elevation change is 7000 to about 1000 MSL and the grades are really rather step or shallow and long. Semis do about 30 on some of those. Going down is OK just coming up is terrible.

Even local driving up the locals hills are an issue. I noticed an improvement when I changed out the rear but really looking to add just a little more.

Joe

JWP Policastro

I had a Judson on my car for about a year. Loved the dang thing. Broke a crankshaft( no relation to Supercharger) Once raced an A up the hills in Mo. and I walked away from that car going uphill. I rebuilt my engine to handle a supercharger, crank, pistons and custom rods. Spent so much money had to sell the Supercharger to do repairs, miss the thing everyday I drive mine. That said if you have an old tired engine I would not recommend it..
Tom Maine

Joe,
I am the Aussie that Tome Lange mentioned in his comments above. I shared all the uncertainties you presently have but took the plunge and am now very pleased I did so.
The comment offered by Gene Gillam (You're not going to gain a lot of top speed ......) is worth reading again. It certainly sums up my experience.
With a limited mechanical background I was able to fit the blower myself and had it tuned on a dyno as recommended.
Should you wish to tap into my experience you are most welcome to email me at robert.woodfull@bigpond.com
Rob
Rob Woodfull (TD 11148)

I'd guess I've got more miles on an Eaton supercharger than most. About 20000 miles in two years.

They are not particularly hard to tune but jet selection is very important. Contrary to what a few others have said...if you have some higher gearing..you can achieve some higher top end speed, but thats not what its all about. It's driveability. I live at 4800 ft elevation and drive over passes that exceed 12000 ft. Without the blower I'm struggling to make the grades in 3rd gear. With the blower I can pull them at 60 in 4th and can use 5th on a lot of grades.

Heat is a big issue so the distributor should be configured (curved) by a pro. I think an oil cooler is a wise investment as well. Premium gas is a must.

MG LaVerne

Joe - the better your engine now runs, the better it will run when supercharged. A 'proper' engine rebuild these days includes balancing of the crank, rods, pistons and flywheel, as the forces spinning around in there are pretty fierce at the speeds we spin our engines. They were rudimentarily balanced at the factory (I've heard to 6 grams), but we try to get less than 1 gram now.

Tuning is easy with a single SU, but it is also critical - we recommend the engine run ever so slightly rich, as even the barest lean mixture can wreak havoc with pistons and rings. If one is in the slightest hard of hearing - and even if one's hearing is great - the car should be tuned on a dyno, to demonstrate there is no lean mixture anywhere in the RPM range.

A stock engine is actually the best engine to supercharge, because the pressures in supercharging a "hot" engine can lead to many problems. Mort (q.v.) had significantly high compression, and has lowered it with a thicker head gasket, to avoid any problems.

I'd be happy to talk with you directly, if you have any questions I can answer.

Tom Lange
MGT Repair
t lange

Joe,
Our TDs are my wife's toys and she drives them hard!!! With the 5.12:1 gearing, it drove me nuts listening to the engines winding out down the highway.
I added a Magnacharger (Moss/Eaton version 1) and MGB 3.92:1 rear end to the '50. Now she regularly cruises at 80mph, and it is only turning 4000rpm.
We also have a '51 TD with a Marshall-Nordec blower and stock gearing, which will blow the doors off a stock TD in a drag race, but must still rev like hell at highway speeds. Wife was running 75mph laps at Michigan International Speedway and I was expecting a rod to launch out of the block or the crank to let go!
With your MGA gearing + blower, you'll be enjoying better acceleration, but where it'll really make a difference is in very good highway cruising and hill climbing with power to spare, without the rpms.
You don't BUY a supercharger- it is an investment that returns great dividends every drive, and if you keep it in good shape, it'll always be worth as much or maybe more than you originally paid. Besides the Magnacharger & Marshall, we now have a S.Co.T. and Shorrock setups waiting for their turn on the road.

JIM
JRN JIM

JWP,

I know what you mean about hills in Arizona. My wife and I attended the GOF West this year in Carefree in our MGA. I had always imagined the area around Phoenix to be relatively flat but was amazed at the number of hills. I don't have a supercharger on the MGA but if I lived in that area I'd have one on it too.

We'd been to one of the Al Moss meetings in Sedona in the supercharged stock TC and definitely appreciated the supercharger there.

I'm sure you'll love it if you get one...and don't forget, not only do you gain torque you gain the "Look at what I've got" factor.
Gene Gillam

Jim brings up a great point I have not really considered. How much maintenance is there with a supercharger?

Joe

PS This has been a superb thread. Thanks a million for all the input.
JWP Policastro

My Eaton blower requires NO maintenance for a full 100,000 miles. It requires no more distributor adjustment than any other MG, and the single carb is a snap to tune (and rarely needs it).

Older superchargers like the Shorrock and Marshall require an external oil line for lubrication, which - if it vibrates much - will fracture, losing all your engine oil if not caught in a hurry. This, and questions about 60-year-old metallurgy - is why a new blower is much better than an old one. I'm not knocking old ones - I have Shorrocks, S.Co.Ts and a Judson - the old ones can work fine. But one of mine will be more efficient and will yield more HP.

Tom Lange
MGT Repair
t lange

Regarding the Moss kits, there are probably more of them out there today than any other type since they have been selling them for close to 30 years. I've never heard of a major problem outside of normal maintenance. The Eaton blower they use (pretty much the same blower most modern kits for old Brit cars use) are very robust and won't require anything for probably 100,000 miles. I have one of their kits on an MGB with a purpose-built engine and the improvement in torque is nothing short of amazing. In stock form it is still a significant increase. I've considered putting one on the TC, and if I do it will be a modern kit, not a vintage one. I love using period-correct equipment but those old blowers offer far less performance and tend to be finicky and wear out much faster.

Your engine sounds like a good candidate, although lower compression works best with a blower. There will be tuning issues after installing, there always are. A dyno is a good idea but you can do a pretty good job with an AF meter also. A carburetor-equipped car will be less finicky about tuning but once you get the blower set up correctly it isn't too bad. You just have to be more strict about keeping things just right.
Steve S

With the Marshall-Nordec, there's a needle sight valve to adjust, a half dozen or more drops per minute. Most of the time, when I look, there's no drip[. Not to worry since it has a sump just like the others and will probalby run forever on that oil. I found that when running, it'll add more to the system which'll drain out after shutdown.
The Moss/Magnacharger was a newer Eaton than the Marshall and was SUPPOSED to be maintenance free, but ever since we first got it, I pull the drain plug every few months and nothing comes out. I squirt a shot of oil in almost as regular as checking/adding oil to the engine. I have no illusion that my tires won't need a shot of air once in a while either, so they get checked regularly. Just doublechecked the knockoff hubs yesterday, too.
Hopefully, the newer blowers will have better integrity, and never need looking at- no one ever checks these Roots type blowers on new cars.
JRN JIM

Steve - The current Moss T-type blower design does not resemble the older Moss blower, as the kit now on offer was put together about a year ago by entirely different people. I would also think long and hard about the need to permanently cut a chunk out of the right radiator stay bracket, as the Moss blower kit requires.

My Eaton blower was designed and engineered by Terry Peddicord, who worked for Moss back in the day, and designed the earlier Moss blowers for both MGB and T-types, to great success. His design has indeed been successful for the past 30 years, which is probably the very best recommendation for my blower!

My supercharger kit sells complete for $4295 in raw aluminum and $4795 fully polished (that sets off a show car like you wouldn't believe!) - I will include shipping for a limited time, so $4295 is the total price out the door, with a completely re-manufactured Joe Curto carb. I see the Moss blower is now $4595 plus shipping, without discounting.

Whichever blower you get, it will be a great up-grade, with virtually no down-side.

Tom Lange
MGT Repair
t lange

Joe,
I think you have gotten a lot of great responses to your questions. For the sake of completeness i will answer your questions about my car.
JWP Policastro, Arizona, USA

"Mort thanks. I do have a couple of questions.

Can you describe if the car ran better with the modern supercharger"
Yes is the short answer. The Judson while nice was 60-70 year old technology and required a separate oil feeder that used a quart of Marvel Mystery oil every 300 miles.

"Is the rest of your car stock -- cam, valves, rockers, etc."
Again, short answer is no. I had a heat issue and replaced my radiator with a 4 core. Fantastic improvement. I put in a 5 speed tranny from Skyhook Eng. Fantastic improvement. I put in a roller lifter cam for a street supercharger. Fantastic improvement. I replaced my stock 5.125 rear for a 4.55. Fantastic improvement. I am using a .085" head gasket to make up for the thinner head and lower my compression ratio. I've had my distributor tuned by Jeff at Advanced. I just put in an oxygen sensor to get a better handle on the air fuel ratio and to keep the carb tuned well. I just got a neat little SU carb tuning kit from Joe Curto and as soon as I finish the tune up it's back to the chassis dyno to check it out. I will report back on horsepower etc. when finished.

"Why did you change?" Answered above

"What rear are running?" 4.55

"Would you do it again?" Absolutely

"Are you running a standard tranny? 4 speed." 5 speed

"How does it run on the highways, parkways, freeways or what they are called in NJ? I remember the Garden State parkway and the Jersey Thruway?"

I live in Yuck NJ. To get anywhere requires a bit of travel. Although I like the back roads with the TD I am compelled to take highways a lot. I have made most of my changes to improve performance and safety. I need to feel a little more comfortable on the Turnpike and Parkway. I do now.

Best of luck,
Mort
Mort 50 TD (Mobius)

Mort thanks. Like you I too have to use highways to go anymore. Just replaced the rear with a 4.55 also. This weekend I did the entire front end including a new steering rack from Moss.

Made the decision to do the supercharger based on all the input. I can't thank all of you enough for all the great input. I now feel very comfortable with my decision.

By the way the steering rack took about 1.5 hours. Really night and day. Just had it aligned. Runs great.

Thanks again

Joe
JWP Policastro

Just wanted to add a comment on the steering. I was able to remove it without removing the radiator. My guess is that being able to push the sterling wheel up gave me enough room to get it out without a issue.
JWP Policastro

One thing I failed to mention is that choke usage becomes much more finicky with a supercharged engine. It is very picky about the mixture so there can be a lot of fiddling required until the engine is fully warm.
Steve S

Steve,
That might be unique to some engines but I have not had that problem with the old or new supercharger.
Mort
Mort 50 TD (Mobius)

Steve I do not know if the choke issue you mentioned is related but one of the things I found in my research was that the warm idle oil pressure needs to be a minimum of 25 psi.


Compression needs to 120 psi and ideally within 10 % on each cylinder. I found this interesting because I have The T Series Handbook produced by the NE "T" Register and it states the following in regards to compression.

max 140. Min 100 var 20 psi.

Based on that we could have an engine within specs but marginal for a supercharger.

The other thing that comes to my mind is the carb tuning.

I'd love to know your model of supercharger and the carb it is running.

Joe
JWP Policastro

I installed an air/fuel ratio gauge and it shows running pretty rich at idle and hits just a touch rich at 80mph.
Since the enrichener is rotated an extra 90 degrees on the supercharger, the "single wire choke cables" on the shelf today are virtually worthless and our "choke" is disconnected, BUT- the car starts instantly every time.
This is with the reproduction SU that came with the Magnacharger.
Do not make the mistake of trying to adapt a Harley carb to the supercharged XPAG! You will really appreciate the "constant velocity" function of the SU slide!!!
JRN JIM

Compression pressure is not the issue, compression ratio is, an 8.0 compression ratio is recommended for a S/C application. The camshaft timing & duration will alter the compression pressure for a given compression ratio.
Len
Len Fanelli

This thread was discussed between 12/04/2014 and 16/04/2014

MG TD TF 1500 index

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