MG Sports Cars

Here's a thought, let's all give RM a Christmas present. Nothing that would break anyones bank you know something like $20,or $50 each. Then we could attend to the needs and with a little luck have some spare change left over.

That'd be a good idea. Bill Davidson told me there's about $125 in the bank account. Not enough to buy the megajolt that Randy Kassad is selling in the classifieds:

[forum.britishv8.org]

We've spent a lot more than that on broken starter noses, and will spend even more unless we do something about it. This would be the correct fix and very likely would allow us to squeeze a little more gas mileage out of the car at the same time.

For my Christmas contribution, you guys buy this and get it here and I'll install and tune it.

Jim

Will we also need the trigger wheel, the cord module and the coil pack. What is different about tbe RM engine from the 455 of 1970.
They didn't break starters. I hate to add enpence and complication to RM

steve

Steve, it can trigger off the distributor's points and run the stock coil back through the distributor. What it adds is a timing map. As you know, the distributor's mechanical and vacuum curves are not well suited to this engine's requirements, as retarding initial timing enough to eliminate kickback means not enough advance when running and the engine runs hot, while mileage and power go away. Nobody was able to make the MSD timing box work and nobody knows enough about the stock distributor to fix it. If we leave it like it is, we can pick one but only one of the following:

1) good mileage, good power, broken starters every now and then without warning resulting in expense and unexpected repairs
2) bad mileage, poor power and response, overheating, easier starting and no broken starters

I'm just giving you guys another option

Jim

OK guys, good news. A certain donor, who I assure you is unlikely to remain anonymous for too long, has purchased the unit from Randy for the RM. So me and my big mouth, guess who gets to install it and tune it now?

This will be a big improvement over what we have now and I think some of you are going to be surprised at what we'll be able to do with it. We'll keep the distributor and coil, lock the advance plate, and use a timing map to control the ignition and the setting will let us retard the spark while cranking so broken starters will be a thing of the past. We'll also be able to map the timing while driving the car (or on the dyno) to get the most out of it. I'm not going to predict we'll improve on the 17mpg we've been getting out of the car lately but it is certainly a possibility.

Jim

I need details for making a donation:

who to make the check pay ale to

where to mail

Ale? Did someone say ale? Ale for one & ale for all! :) :)

Sounds better now. Hope you have fun installing it. Can we get a good map without a dyno?
Steve

Shouldn't be a problem.
Donations:
[forum.britishv8.org]

Good for what ales you, Carl

Tell Bill PayPal would be helpful.

Bill,

be on the lookout for my donation finally got around to sending it toady.

Merry Christmas RM

PJ

Good looking project. I have a question about the Jaguar IRS and you appear to be far more technically knowledgeable than I am. I am concerned that the wheels will be allowed to drop enough that the U-joints will bind and something might break. What would you use to make sure the rear wheels only drop as much as the U-joints can take as an angle? I hope this made some sense.

Not that I plan on jumping the car into the air where this could happen, but I just want to make sure the car is safe.

Not a problem Henry. The shocks we chose limit the downward motion. Now, these are a racing spec coil-over and do not have an internal bump stop so if frequent full extension of the rear suspension is anticipated (as in jumping the car) an external limiting strap or a shock with internal bump stops should be used. The latter has the unfortunate side effect of limiting suspension travel however, are not available in the same length and would have to be positioned differently, and are larger in diameter and therefore more difficult to package. We did use an external bump stop for compression travel. There are compromises with the design as in any other, but with the long travel, being able to keep the wheels on the ground has not been one of them, nor has the ride.

In further news, we will have a work weekend scheduled at Blackwood Labs within the next few weeks. There are three projects here that may be involved in that work weekend depending on who shows up to work on what. The Roadmaster is one of those three and there are several tasks that need attention such as fixing the door lock, adjusting the side windows, etc and Randy is getting us a Molex connector so maybe we can install the MegaSpark module as well. The IRS subframe cushions need inspection and possible replacement also. The other two are the Chump car and Dan's TR-7 conversion. Anyone who wants to is free to stop by. I'll post more info as it becomes available.

Jim

I have taken the car out driving around a bit a couple of times now. It still kicks back and isn't real happy starting in the cold. And with the timing retarded a bit it feels like we've lost the edge on the power curve... it's no longer so comfortable with that 2.88 in 5th gear as it was before. We should be able to remedy both of those problems once the MegaJolt goes in, and should be getting the connector for it before too long. I haven''t had the car on the lift yet... Need to check the rear crossmember bushings and shim them up so we don't have to worry about breaking another shock. But, my RD is on the lift. I probably won't move it until I have some help as the posi makes it harder to maneuver. Those are some other things we can do together which would make for a fun weekend, not too strenuous, pretty easy, more or less clean work with good results.

Jim

Hey Jim, all:

(Been awhile since I've caught up on RM. Holidays, etc. :-) )

Went back and reread some of the 2011 posts when we just got the car on the road.

IF we ended up set up for manifold vacuum-- why have we been breaking starters?

Since I last timed the car it had an MSD added, a spark control box, it killed a coil, it's been to the dyno... and now it's killed it's 3rd starter!

It's nice that we have this MegaSpark unit (I guess), but you'll have to go back to the dyno to get it right! (We run a programmable 123Tune in the racecar. It is AWESOME, but I wont' lie that it was every bit of $300 dyno time to work out all the timing points!)

I can't help but think we should stop throwing extra parts (that aren't fully understood by all possible users!) onto the car and Keep It Simple, etc. We could have recurved that current distributor to do what you want. (Or Schlemmer could have). It just needs more mechanical timing. Open the gap, stiffen the springs (low compression).

In fact, as a Back Up, I'd be happy to do that. Grab a junk distributor and lock that down for the MegaSpark. Send me the good one...

$.02

M

PS: Emily says when I spend time reading this thread I'm "RoadMasterbating". I thought that was hilarious... :-)

Careful Max, I think this is supposed to be a family friendly forum ;-) but I think it's funny too.

To each his own I guess, somebody had to do something about this kickback problem and it's been well over a year and nothing had been done. Three starters in less than 2 years is completely unacceptable. So I ventured to drag the group kicking and screaming into the present. Or near-present since MegaJolt (That's the correct name btw) has been around nearly a decade and a half now. So it's actually become "old technology" and as old codgers we are now free to embrace it at last.

As for the dyno, well if you *have* a dyno, and the money, you might as well... but lots of tuning can be done with neither. I expect we'll quickly get it as close or closer than it was after Texas without it.

And this *is* an effort to simplify things. Get rid of the advance/retard box that NOBODY knows anything about, maybe get rid of the MSD box as well, still have to see about that part. Get rid of the mechanical advance and the vacuum diaphraghm. Less parts to wear, tear, and break, and *way* easier to adjust.

And really Max your offer to help is appreciated by all but you're a little late. Do try to keep up if you can. Now if you had a good solution for the wimpy stock heater fan that was a bolt-in replacement without cutting the heater box that would be a good place to apply your efforts. I don't know why, the fan runs fine and in the right direction and on the bench a similar heater box blows plenty of air and there isn't any blockage of the heater core fins, but we get barely a wisp of air out of the vents. There simply has to be a stronger motor with a wider squirrel cage that will fit the opening. We just haven't found it yet.

Jim

JIm:

uhm... you've flipped OPEN the vents, right? :-) (Manual control!)

For awhile there was a Grainger fan that was a near match to the MGB one in diameter, shaft size, etc., and it was only $25. (Whereas a Moss one is like $70). That might be an option.

The earlier, taller motors will work and seem a little stronger. (Something '62-'67, I think.) IF you want to scrounge amongst the ranks....

I don't remember anything about the heater (I think it was IN already?) but if it isn't sealed inside the box then it doesn't "heat" very well.

(It's NOT a great system, either way. :-( )

M

Steve and I worked on the car some over the weekend. The issue with the coil-overs is now resolved and we should not have to worry about breaking another one. The idea of spacing the subframe down was not feasible because of the 6 point mounting so we simply cut about a 1-1/2" hole in the sheet metal above each upper mount and drove in a heavy PVC plug with a domed center which gives the necessary clearance. It's not a perfect fix, but it should serve the need.



While on the lift we noticed that the bottom of the tank was badly bulged in and seeing only one fairly small scratch decided it must have been due to suction. So we blew the tank back out and drilled a hole in the misfit cap. Since Dan or I (probably me) was responsible for losing the cap when we turned the car over to Rick after Omaha on our last fill-up it sounds like I need to buy a new cap. But if someone took a notion to donate one I'd certainly be grateful. It is the type (OEM) that engages the inside of the filler neck, but we could change out neck and cap both if matching ones were available.

We moved on to the ignition. I told Paul when he bought the MegaJolt that I'd install it. And I will. I didn't know at the time that it would not work with the stock distributor and Pertronix module, but required an EDIS ignition system but I try to keep my word if at all possible. So Steve and I removed the crank pulley and put it on the small bench top mill, where I drilled and milled the 36-1 tooth pattern needed for the crank trigger, and then we made a mount for the pick-up that bolts to the unused mechanical fuel pump location.





Then we mounted the EDIS coils and module using extra parts that I had on the shelf



And somewhere along the line made a trip to the pick-n-pull for connectors and stopped by the hardware store for some stainless fasteners and standoffs. Steve bought a new set of coil wires to work with the EDIS coil packs and we got everything done except the wiring connections before we'd had enough.

I'm not sure how long it'll take me to finish up the wiring. If my car's any indication... well let's not go there. But I won't be able to help get it to Colorado and other points West so you guys might want to be thinking about how you are going to get that done. I'll let you know as soon as it is running again.

So some might ask, WHY? The best reason I can give is that we could not find a happy balance between the timing needs for starting, idle, midrange and WOT using what we had. I don't know why that was, we certainly tried. And broke starters. Again, and again, and again. Well, no more. Early BBB engines ran just fine with distributors but ours never did. Perhaps the cam, perhaps something else. At any rate the EDIS system is very good and will run the engine even without the timing signal from the MegaJolt. No timing advance, but it'll run. And with a .050" spark gap recommended, which can't hurt. The MegaJolt enables any setting for advance on start, at idle, and anywhere else, based on vacuum and engine speed. So we can easily create an optimized advance map using a laptop. That should allow us to get the best mileage we can as well as the best power, while being able to start easily with no kick-back. It's a bit of trouble to get there, but it's the best way I know to solve those problems.

Jim

Once again Jim, you, Steve and everyone else has gone way over and above the call of duty.
And it's very much appreciated.
If the car ever gets out this way, or if I trek east sometime I would love to work on it as well.

And p.s. the chump car trans is nearly done if you still need it.

Cheers
Fred