MGB Roadmaster

Started by BlownMGB-V8, October 23, 2007, 01:27:13 PM

Previous topic - Next topic

BlownMGB-V8

Almost have the Roadmaster ready for the Louisville meet. I made a new surge tank and it's installed. Re-routed the drain so it can function as it should. I'd be happy to explain the details in person if anyone is interested.

IMG_0004.JPG

I also installed the new fuel pump that was bought for the car. Honestly guys, I don't know if this made any sense. That's at least the 3rd pump of that type that has been on the car. This engine has the ability to instantaneously suck down fuel like almost no other one in the fleet. If we are having a starvation issue maybe we should bite the bullet and install a *new* high flow pump of a type suitable for the use.

I installed a TR6 heater valve on Jim Watson's recommendation, then found it needs the GT6 valve which works opposite of the TR6 one. (They look almost identical) One of those is on order and may get here tomorrow or the next day. If so I will install it. Anyone want to buy a new TR6 valve? (Hasn't had fluid in it yet)

I also installed the new replacement steering column we've been carrying around for a year, after checking the rack shims and universal (both good). The play is gone, part was in the column's slip joint and part was at the steering wheel hub. All gone now. Charles and Mikey are working together on an EPS unit using the old column, which is good because it fits better than the replacement.

The heater knobs have mismatched gearboxes, one old style and one new. Sorry, it's all we had to put in at the time. So for now, I've installed a new knob on the left so the heater valve can be adjusted. We need an old style gearbox to fix this problem.

Haven't had time to do anything about the gages yet but the good news is that I have a full set including the voltage regulator. The tach can be run off one coil pack and the speedo can be run off a cable. I see no real problems there, it just needs to be done.

Jim

MGBV8

The metal fuel line to the carb body needs a brace. It was leaking fuel at the carb due to vibrating loose.
Carl

BlownMGB-V8

While I had it on the rack I test fitted two A/C compressors, or rather tried to. A Sanden and a GM A4 "pancake" compressor. Neither one would fit in the low spot on the driver's side between the frame and the block. That spot is definitely a non starter.

That leaves the location in front of the driver's side head, and above the oil pump drive where the distributor used to be, basically two variations of the same place. The A4 should fit here. The Sanden might but it'll be very tricky, and hood clearance gets into the picture. (Incidentally I do not have a known good A4, just a questionable take-off.)

This location will require a complete re-routing of the upper radiator hose, including re-welding of the thermostat neck and extension, but this can be done. However, nothing will happen here until after Louisville.

Jim

BlownMGB-V8

OK, I've done everything I will be able to do before the show. As it now stands, the car is in very good shape and comfortable to drive. The steering is a little stiff from the solid bushings in the column but hey, no play. The new EPS will fix that.

It still has a lean bog on acceleration, the pump can't keep up. 3rd synchro is unchanged.

But hey, temp holds steady at 190 with no problems, and best of all it now has a full compliment of functioning gages!

Stock Fuel, Tach, Speedo, and Temp. Curved bezel style. White faced Oil pressure and Voltmeter in the center. Doesn't look bad really, at least it is symetric.

I think the fuel gage will be accurate but still have to check it out. At about 3/4 I put in 4.4 gallons.

The tach seems reasonably close. Shows about 1700rpm at 70mph in 5th. That was a trick btw, I wired the supply from one (EDIS) coil pack through the tach, tried both polarities and picked the one that gave the lower reading, then used a screwdriver to adjust the calibration pot for the lowest reading. Didn''t have a dwell tach to compare it to but at least it is usable and best of all, no mods to the 4 cylinder tach. We could run Dan's spreadsheet to see how close we are, the rear tire size is 245/45-17.

The speedo reads 10% low, so 70 mph @ 77. With a 19 tooth gear installed, a 17 should bring it to within 1 mph. That was also a trick. Hey Guys! I found how to use a stock speedo cable with a T5!!  All you need is the nut off a GM speedo cable. File the inner cable end down so it fits in the GM drive gear, then cut the threads off the big nut on the MG cable leaving a washer. Sand down the outside of the washer to fit in the GM nut (a belt sander works nice, letting the washer spin on the cable to get an even perimeter) and then bolt it up! Presto!

The temp gage is wired to the wrong sender but it is usable until we can install the correct one. I didn't have an identifiable MGB sender to use. At 190 the needle is a bit south of the "N". I made a mark with a sharpie. With the right sender it will read like any MGB.

So you may ask, why didn't we use stock gages originally? Mainly because we didn't know how to make the speedo and tach work right. We did not have EDIS at that point so we couldn't use the single coil pack trick, and we did not have a mechanical drive for the speedo. Thanks to Steve DeGroat for that btw, I pulled the drive out of the 4 speed he brought up for the Chump Car and it works great. (Also Steve, the tool kit you donated for the RM is now back in it's spot behind the driver's seat.)

And that's about it.

Rick, I will call you a bit later to coordinate.

Jim

lawnvett

Wow Jim you've gotten a lot done!

BlownMGB-V8

Yeah, I sorta went to work on it.

I ran Dan's spreadsheet. Assuming a 2.88 axle ratio and a .63 OD, 77 actual mph (70 indicated) should be about 1800-1850 rpm, which seems to indicate there is enough adjustment in the calibration pot to get the tach centered on the actual engine speed. But hey, at this point an error of maybe 150 rpm max at that speed is a great result. I'll certainly take it.

I also remembered, I didn't have a firewall grommet for the speedo cable... well actually I did, I took the one out of the Chump Car and set it on the dashboard of the RM. Then when I went to use it I couldn't find it. It still may show up but that's one thing more we need.

Also I wasn't able to get one of the retainers on the speedo. The one to the inside naturally. My hands are just too big I guess. The speedo looks cocked a little because of it but there's not much I can do about it.

Also the windshield washer bottle leaks. It looks like there might have been a repair job on a crack in the bottom of it that failed. Don't know if I have anything that would work any better, we should probably get a new bottle. (The round type)

Jim

BlownMGB-V8

Here's a shot of the dashboard:
IMG_0022.JPG

BlownMGB-V8

Not much luck so far finding a voltmeter with a black face, white needle, rounded chrome bezel and flat glass. Haven't looked at oil pressure gages.

Installed the 17 tooth speedo gear, the needle wobbles a bit now and it reads a smidge low but that's about as good as we are going to do with those 2.88 gears. It's a couple mph low at 50 I think.

Tightened up the throttle spring just a bit, it was light anyway. Maybe that'll eliminate the need to blip the throttle to get the idle to drop.

Fuel pump: I found this Bosch 44 knock off which seems to be pretty common. Costs $30. For that price I just went ahead and ordered it. Hopefully it will not overpower our Holley inline regulator.

danmas

QuoteI ran Dan's spreadsheet. Assuming a 2.88 axle ratio and a .63 OD......

Jim,

What are the gearbox ratios in the Roadmaster? 1st through 3rd.

BlownMGB-V8

Carl might know. I think it is a V8 unit.

Jim

MGBV8

That was my spare, so it is the same as the one in my B.

1991 Camaro V8. 1st=2.95  2nd=1.94  3rd= 1.34  5=0.63

Corrected the year: Both T-5s are supposed to be '91 models.  That is what i posted in older threads. I confused the years with my my two 1989 Rover 3.9 engines.
Carl

mowog1

Dennis Gage liked the Roadmaster.....as did the guys from Hagerty Insurance.

Dennis Gage with Roadmaster.jpg

BlownMGB-V8


BlownMGB-V8

So I've been taking the car to some of the local shows and feeling out a few people whenever they want to know the asking price of the car. So far, $30K has been seen as too little, so I decided to see if I could find out what wasn't. Yesterday's experiment was for me to name a price and ask for an honest reaction so I asked, "What would you say to $45K?" The response was, "If I had it right now and you'd take $35K I'd go right to the bank for the money." That was before he knew that the car had a history and said that would make a difference for him. This from a guy who occasionally buys/sells. If we could get that kind of money out of the car I don't think any of us would be unhappy with selling it. 45 may be a fair ask.

In the meantime, I have purchased most of the parts to upgrade the fuel delivery system. Some parts have yet to arrive and I think I need to go buy one more fitting. I'm keeping receipts. That is the 1st priority at the moment, followed by the steering upgrade Mike is working on, which is also a safety issue since the U-joint currently is not properly secured. I really cannot turn the car over or let anyone drive it until that is fixed. I can take the risk myself, and I don't feel it's likely to come loose, but... well you never know. The heater controls are finally fixed, though they are a little stiffer to turn than I'd like, the dash lights don't work, the speedo is not properly secured, I haven't had the chance to do more than just look at the A/C compressor mount, and of course the diff is noisy. That's everything I can think of at the moment. If things would quiet down a bit around here I was thinking about loading the megaspark software on my laptop and using it to calibrate the tachometer but that is a pretty low priority. All the gages work well though the speedo wobbles a bit and we will probably have to replace the inner cable to fix that. My fault I suppose, I had filed the end down to fit the 22 tooth gear that came out of the B/W 4 speed (it was rock steady then) and when I got the 19 tooth gear it was loose and the needle wobbled. Oh, also one of the headlight buckets fell off and I just stuck it back on, so I need to pull that back off and make sure it is right. Just the fact that I'm identifying these smaller details though says much about where we are with the car.

The second weekend in September is the GS Nationals in Bowling Green. We may finally be positioned to make an appearance there provided the fuel system and steering are sorted out by then. The central feature of the meet is the drag strip and we will be expected to make at least one run down the strip if we are to have any credibility with this crowd. If you will recall, they are the people who were largely responsible for our being able to get the engine for the car in the first place, Dave Enneking donating the initial 400 BBB and Allan Mandeen providing the '71 455 (which is the lightest BBB btw), as well as things like flywheel, bellhousing, intake, cam, etc. It has long been on our to-do list to show up at this meet but up to now the car hasn't been ready.

Next Saturday is the Dayton British car show and I plan to be there with this car. Matt is also going, with his SBC/Jag. We look forward to seeing several of you there.

Jim

lawnvett

I hope you are having fun Jim, it's your turn.

BlownMGB-V8

It's getting better. Yesterday at the Dayton car show Mike Moor handed me a ready-to-install Electric Power Steering conversion for the Roadmaster. He and I are both convinced that this will completely transfom the character of the car.

So, a bit more work for me to do but it'll be worth it. I'm beginning to wonder if another Roadmaster weekend might not be in order though, as the job list is increasing. As it now stands:

-Install the EPS
-Install the fuel supply system upgrade including return line
-Fabricate compressor mounts
-Troubleshoot dash lights and install rheostat
-Calibrate tachometer

And then a more long term issue, fix the noisy rear end.

But the drive up and back was enjoyable, about 70 miles each way and mild weather. The car performed flawlessly if you discount a couple of minor things to be addressed by the list above. As usual it drew a crowd all day. I even did a video interview for a show to be broadcast on a local TV station.

Jim

lawnvett

let me know if you schedule a work on RM date, I'll try to be there

BlownMGB-V8

Thanks PJ, it means a lot. I'll have to get back to you though on plans, as scheduling might be a bit tricky.

Jim

BlownMGB-V8

Yesterday I took the car to the 98th annual Four Corners Party of the American Legion's National Convention, held in Cincinnati this year, a rather well attended event as you might imagine. I parked it right next to the doors in a spot of shade opposite the food vendors and parked myself in a folding chair nearby in the draft of A/C coming outside and was there for questions and such. We got lots of attention as practically everyone who came and went stopped to admire the car, take pictures and/or ask questions. Regrettably there were not a lot of young people, our target audience, but there were a few.

Because Rick's "For Sale" sign remains in the back visible through the hatch, I got quite a few inquiries as to how much we wanted for it, and that became an interesting thing. I would say $45K and invariably the person asking would say something like, "That's very reasonable, I would have expected 50 or 55." We may still be asking too little for the car, but if we hope to get that sort of a price I expect we will have to fix the noise from the rear, whether it is from gears or tires or both.

The car continues to improve. On the drive home I noticed some trailing throttle understeer when briskly changing lanes and lifting off the gas, and this means we can and should go ahead with the installation of a front sway bar to induce a little understeer and counteract that. It wasn't bad, not to the extent of causing the tires to slip, but also does not instill confidence. The MGB tends towards a little trailing throttle understeer anyway, which can be put to good use in very tight hairpins such as on an autocross course, but I think we have a little more than what is commonly there. It is probably more noticeable now due to the vastly improved light steering from the EPS, and possibly aggravated some by the Fusion tires on the rear. (I should probably check the tire pressures) I do have a few swaybars to choose from, it will require just a little fabrication for mounts, but I don't think we have the downlinks that we need, so if anyone has a spare set of CB downlinks they can donate please send them along.

Speaking of the EPS: What a pleasure it is to drive the car on the freeway! It was really the first time I'd been able to take it out for any distance at all and I've got to say the experience is vastly improved. Every bit of control is still there but there is now just a wee bit of isolation from road shock and it is enough to make all the difference in the world. The feel is very much like that of virtually any new car that you might choose to drive in terms of noise, vibration and harshness (NVH). The small steering wheel is just fine in terms of steering force with the control knob turned almost all the way down, though it does lend a bit of quickness to the steering that some may like and some may not. Incidentally, the control pot that comes with the Bruno unit appears to be a typical pot with dead zones at the end and as such gives erratic results when it is turned to the stop. A pot with no dead zones at the ends would be better, or in this case perhaps a fixed resistor instead.

Kudos to all who have helped develop the EPS and especially to Mike Moor who donated the unit complete and ready to install. This is most definitely a ground breaking improvement to the MGB and something that will improve every car it is installed in, even a completely stock 1800cc MGB.

I have plans afoot to go drive Corinth road (that's the, "little Dragon", right?) Which will let me evaluate the new steering in the twisties. Hope to do that this week if possible, and if I get the new fuel pump installed in time, take it to the Buick GS Nationals on my birthday weekend. After that I'll have a look at the A/C compressor mount.

I want to apologize for not scheduling a Roadmaster weekend so those of you who wanted to could come and help. Scheduling has been a problem and other things have taken priority as I'm sure all of you very well understand. Meanwhile I've taken care of a few small issues as I've been able to. I'm afraid the situation will remain unchanged until after Townsend. By then if matters have progressed as expected about all that will be left to do is work on the A/C system and the noise at the rear. Maybe improve the seat belts. If we are able to address those concerns in a satisfactory manner, we may at that time want to reconsider our decision to sell, as the car will then be a completely modernized and thoroughly enjoyable ride, almost the pride of the fleet you might say, and I'd really be surprised at anyone who wouldn't enjoy taking custody of it, even if just for a short drive. (And this comment coming from a convertible guy too!)

Jim

MGBV8

Trailing throttle oversteer also know as lift-off oversteer?  I experienced that in my MGB at Grattan Raceway. I immediately got back on the gas.

You wrote this:

QuoteOn the drive home I noticed some trailing throttle understeer when briskly changing lanes and lifting off the gas, and this means we can and should go ahead with the installation of a front sway bar to induce a little understeer and counteract that. It wasn't bad, not to the extent of causing the tires to slip, but also does not instill confidence. The MGB tends towards a little trailing throttle understeer anyway, which can be put to good use in very tight hairpins such as on an autocross course, but I think we have a little more than what is commonly there.

I believe you meant this:

On the drive home I noticed some trailing throttle oversteer when briskly changing lanes and lifting off the gas, and this means we can and should go ahead with the installation of a front sway bar to induce a little understeer and counteract that. It wasn't bad, not to the extent of causing the tires to slip, but also does not instill confidence. The MGB tends towards a little trailing throttle oversteer anyway, which can be put to good use in very tight hairpins such as on an autocross course, but I think we have a little more than what is commonly there.
Carl

BlownMGB-V8

You are correct. Where's the spellchecker when you really need it?

Jim

BlownMGB-V8

Fuel system upgrade: The pickup tube had popped out of the bracket that holds the end down which resulted in leaving an unusable 2-3 gallons in the tank. Fortunately that is now the return line so it doesn't matter any more. I've plumbed in and hooked up the new filter and pump, but the regulator has to be replaced too as it is the wrong type for the new pump and I'm working on that now. With a return line it has to have a bypass regulator rather than the deadhead regulator that it had. So I've got a new one out there to put on it, just have to switch around some fittings and a bracket, and put a lighter spring in it for carb useage.

As it stands, we have a 1/2" line from the tank to the pump, then the 3/8" line that Carl installed to the regulator, then a 3/8" hose to the carb. The return is 5/16" and my concerns that this might restrict the flow and raise the pressure at the regulator were unfounded. (I've tested that) The carb will get full flow, with anything over the regulated pressure returning to the tank. With a bit of luck I hope to finish that today and test to see if the bog has gone away.

The gas gage now reads correctly, but the needle doesn't go down far enough towards E. I wouldn't run it below 1/8 of a tank.

Jim

BlownMGB-V8

OK then, status report on the fuel system:
First, I was mistaken about the 5/16" return line not increasing line pressure, I had the wrong gage on the thing. It does. About 8psi in fact. So I got that wrong, oh well. Set to the minimum there is a very slow drip into the throttle bores. The easiest correction will be to plumb the deadhead regulator back in as a second stage and since I had broken the old one and ordered a replacement I will do that when it comes in. That will allow the bypass regulator to take the pressure off the pump for long pump life, and the deadhead regulator to hold accurate pressure to the carb. Should be a superior arrangement, 2 stage regulators are commonplace, and flow won't be restricted. I should be able to set the first stage to about 15 psi.

So I took it up to the gas station. There's still a slight bog when the secondaries are opened, I think with that Rochester you can tighten up the spring on the secondary flaps and get rid of that maybe, at least that's what I've heard. Aside from that it seemed to work like it should. There was no evidence of fuel starvation that I could tell and I wound it up pretty good several times to check. Lots of power. Pardon me for abusing the tires but I can let y'all know that it is capable of breaking both loose at the same time and laying a pretty even double stripe 3/4 of the way up my driveway and more than that if I hadn't let off. I think it'll be OK at higher speeds but there's only so much I could do between here and the gas station.

So sorry about the mistake, and breaking the regulator, or if I didn't do it right. I suppose y'all could dock my pay...

Now who is willing to pay for the parts? I have spent $344.98 on parts for repairs to the car while it has been here, not just on the fuel system but also fixing things like the heater valve, gages, and so on. I've done all the labor for these repairs, I don't think it's quite right to also expect me to pay for the parts.

Jim

BlownMGB-V8

I watched a youtube video and adjusted the secondary air flap spring 1/4 turn tighter. It had been hanging up a little. That made a definite improvement and power delivery is now smooth and consistent. Took it out on the freeway and up to a hundred or so it continues to pull strongly. (Didn't go much over that I don't think, but the speedo needle was bouncing a little.) Under some conditions there can be a very slight hitch in acceleration but you're quickly past it and I only noticed it once or twice. Normally not even there.

I began to drive the car a little more aggressively. It likes it. Very good around turns and tight corners. The car has definitely become much more fun to drive.

I think it could benefit from a front swaybar, and if someone will send a pair of CB down links I will mount something up, probably a stock 5/8" bar. It'll require modified mounts but shouldn't be difficult. I'd say that's all we really still need to do to it.

You guys need to drive this car. I know you will like it.

Jim

BlownMGB-V8

Done with the fuel system. Fuel pressure set at 7psi, rock solid far as I can tell. It likes 8 psi better, but dribbles a bit at that pressure and 7 is recommended so that's where it is. Maybe slightly more tension on the secondaries flapper spring might make it just a little smoother, probably worth trying. I have the bypass regulator set to about 8psi and the deadhead (Holley) regulator set to 7. That's because when I first plumbed it the Holley wasn't regulating but was leaking past the valve. Had dirt, teflon or something on the seat and a blast of air cleared it. It's possible running a higher intermediate pressure could benefit top end performance, we should watch for pressure drop if we ever put it on the dyno again.

It's great to have good smooth reliable power though. Does a great job through tight corners and works well in transitions. Starts easier too.

Jim