MG Sports Cars

What year/style mirror do we need? I can put out an ABP to my two British car clubs.

I thought the correct lugnuts would do the trick.

Donations to the Roadmaster Project can be made to:

Bill Davidson, Treasurer
7208 W 54th Terrace
Overland Park, KS 66202

913 677-0884
Bill74mgb@yahoo.com

Checks should be made out to:

British American Deviant Automotive Sportscar Society
or
BADASS

Wondering about your trip from Durham, NC to Richmond, VA. . . .

Here is an unsolicited email I think everyone can enjoy:

My name is Greg Porter, and I live in Durham, NC. I was at southpoint mall today and saw the Roadmaster project parked outside. I just wanted to say that this car made my day. I have been a fan of the MGB-GT since I first saw one, and seeing a V8 swapped MG is truly awesome. My friend and I looked over the car for a good 10 minutes in awe of its greatness. Thanks again for building an awesome car

Greg Porter

Oh... yeah. I'm back. :-)

Okay, about the Mall: Emily wants to know if any of the other Wives have driven the Roadmaster? Cuz.. she did. :-) (I was passenger.) Did prolly 30 miles down to the mall and back. (Her first car was a Nova. Then a Chevelle. She likes Big American Iron.)

Yeah, we parked in a conspicous spot-- out in the middle of the lot! Easy to see....

RE: Trip. Some highlights here (as long as I'm responding) and then seperate posts with different topics. (Actually, look under the Conference thread, cuz some of them are more appropriate there, maybe?)

a) Vibration is GONE. Two hours up to Petersburg-- 60 to 75 mph, no problems. :-)

b) First gas stint: didn't do well keeping track of mileage around town, so added an estimate to the trip driving. It came up at only 15 mpg. HOWEVER--- set a trip meter on the GPS (I'm learning...) on the drive back and got 17 mpg! So, it is better.

b-2) If I had to hypothesize about why it's not MUCH better, I would hazard a guess (that I could maybe prove with a Plug cut-out Test) that the primaries are rich and the secondaries are lean! This would explain the stumbling/pinging issues in the high end and the lack of much fuel economy improvement. (The revs being much lower, we are now definitely in the primaries while cruising! (And, might have been before, too, I don't know...)

c) Gauges. (This ties into the BMTA). Talked with Peter Bayer (Nisonger Instrument) re: the Stewart Warners. A synopsis:

1) Fuel Gauge. "Check the grounds. They need a good ground AT the Sender (dunno, will check) and AT the Gauge!"
2) Re: Speedo. "Is it stable?" "yes, just wrong". "Sounds like someone didn't do the math right and needs to recalibrate." (NOTE: new axle, we needed to do this anyway!!). I found the speedo read nearly half what it should. REad 40 when the GPS said 80, but would also read 37 when I was doing 70. Also, the odometer seemed to come up at very nearly half-mileage (just not perfect.) So, we should do that calibration again.
3) Tachometer. I explained it's behavior to Peter and while it was VERY stable on the drive back (and I'll work out the speed/rev calculations in another post so that we can see what's going on) his conclusion was: "Sounds like a bad tach". :-)

More later. Car was fine-- never grabbed a tool. A few noises, small coolant leak somewhere (green globule). Car was much loved and liked, and got a special parking spot @ Moss Motors for the day. :-)

At this point, my biggest worry for the enjoyment of the car is that the lack of good tune makes you unconfident in getting on the gas, accelerating hard, or... showing off. :-)

M

PS: CARL: passenger side mirror needs to be gooseneck, long base style, with CENTER attachment mirror. An exact match would be NOS or used, only. They haven't made that style of mirror in years, and the new goosenecks are bent too sharply, and don't work for tall drivers (like many of us are!)



Edited 1 time(s). Last edit at 03/03/2013 04:25PM by madmax.

Glad it was an uneventful drive up & back!

I still maintain we should pass the hat & spring for a brand new carb.

I thought the carb was good on the dyno in Texas.
Has anything changed?
If you replace the carb, can I have mine back?
Steve

Max Did you have any close calls on fuel? I failed to make 150 miles one time.

PJ:

First fill was 10.2 gals. 2nd was 8.7. We heeded your warning. :-)


RE: carb. It was "good" on the dyno (I wasn't there-- can't say for sure) because you pull to WOT. Thus, as long as the OVERALL mixture is good, it doesn't care. So, very easy for the primaries to be rich and the secondarys lean-- but open up both and the overall mixture is good enough, etc.

Also, there could be a "change" in the tune, somehow, but what I'm experiencing seems to be a lot of what Steve D. reported in his experiences.


I have a book on Rochesters. The carb has to come out to check for Idle Air bypass (on the base) and a few other things before you do any performance tuning.

The question is: do you bother to tune to this camshaft or wait for a milder one?

My current thinking is lets just tune to THIS cam so that everyone can enjoy the car this year. But I would strongly suggest marking what the current adjustments ARE (as the car is driveable, just not fully enjoyable) before we going messing everything up! :)

$.02

Last point in regards our Mission to get the youth involved: Emily took the Roadmaster to her high school today! Be curious what comments THAT garnered! :)

M



Edited 1 time(s). Last edit at 03/04/2013 11:05AM by madmax.

Allright Emily!! It's great that somebody did that. Bet the kids crawl over it all day. It's great to see the car out doing what it was intended to do.

Did Steve change the carb before or after The V8 meet last year? Regardless, I'm glad somebody who is more sensitive to the nuances of carb tuning is looking at it (Max). I drove it a lot at the meet and was certainly less sensitive to misbehavior, but that's probably reasonable since I wanted to see it do good.

You guys keep it up and you're going to make a very fine vehicle out of this old sow's ear.

And to think when all this started all we wanted to do was prove the 455 engine swap was possible.

Jim

I changed the carb before the V8 meet.

Steve

PROBLEM:

Battery was flat at the end of the day and Emily had to call me to jump start. Soon as car was hooked up-- fan started running!

Not the adjustable sender-- it did nothing. So, what's up? Car was dead cold. It was 4:30 pm and she'd last driven it at 8 am at the latest.

I found a breaker/fuse looking thing lying on the passenger floor, marked 15A (two-prong, metal casing.) The RH (pass/upper) fan was the only one spinning-- this breaker-thingy looks like it fell out of the LH circuit. I removed the RH (20A) fuse and the fan stopped. I installed it in both the LH and back in the RH sockets and the fan did NOT start up again.

DAN Masters: is this a shorted relay? Other thoughts?

I'm never in favor of ancillaries running without the ignition key on, and this is a perfect example-- in kept running, somehow, until the battery was flat. :-(

Have we seen this before? And why is this metal-casing "fuse" in the socket rather than just a "normal" 20A?

M

Next Post:

GEARING and Tachometer readings.

With a known speed via GPS (70 mph) and a known gear ratio (4th gear is 1 to 1 and the diff is 2.88), and the known tire size (245/45 x 17 rear) I can report the following:

I was getting a tach reading of ~2800 in 4th gear doing 70 mph. In actuality, I was doing 2638.

I was getting a tach reading of ~ 1780 in 5th gear. BUT... I don't know what 5th gear is in this T5. Is it .62? In which case, at 70 mph we are only lugging 1636. However, if it is a .73 5th gear, then we are doing 1925 @ 70mph whilst in 5th gear.

I guess my answer here is-- WHEN the tach is reading steady, it does NOT seem to be that far off! (A couple hundred, maybe.) It's just that it goes wonky..


Peter Bayer (Nisonger INstrument) also mentioned that the Lucas tachs don't like Pertronix. I did not get a chance to ask about the SW-- as the tach was never that steady on the drive up, I gave him a very bad impression of it! It was far steadier on the drive home (how else could I have gotten the above readings? :-) )

M

Thanks for the write-up(s), Max!

I run a Pertronix with a stock (V8 mod) tach. Works okay.

Overdrive 5th is .63. Sounds like the tach is reading right where we want it.....a bit higher than actual. ;)

Thx, Carl. Sounds like our 5th gear, 70 mph cruising is then an actual tach reading of 1662. :-)


So..... TOP SPEED:

Using the same above formula and the peak HP point of 4800 rpm, the Roadmaster is now capable of:

4800 x 25.68 x .002975 / .63 x 2.88 = 202 mph. :-p

(before it was only 164!)

I seriously doubt the car could actually achieve those speeds-- it only has 273 hp @ 4800 and the wind resistance and rolling inertia increase dramatically, esp. above speeds of 150 mph. (REM: Bugatti Veyron. The first ~300 hp get it to 150. It needs the other 700 hp to get to 253mph!)

HOWEVER--- given a long enough straight, I would think Roadmaster could hit 140. If anyone had the balls to TRY... :-)

M

Fan Relay? I thought Dan M had that fixed.

Jim

Quote:

Fan Relay? I thought Dan M had that fixed.

I thought so too. What did we do to it in Texas?

The metal thing is a circuit breaker. I don't know who put it there instead of a fuse or why.

I'm stumped. The only thing that will operate the relays is a grounding of one or more of the black/green wires from the relays to the temperature switch, or for the switch itself to operate. Possibly one of the B/G wires has pinched against the body somewhere and is grounding? Pull the B/G wires from the switch and touch them to ground - the relays should come on and off as the B/G wires are grounded and ungrounded.

I suppose it's possible for the relay to short, but if it did, it would have stayed on when you pulled the fuse and replaced it. Possibly the fan current is too high for the relays, and arcing during opening and closing could pit the contacts and make them stick occasionally. If so, we're screwed! These relays are rated at either 30 or 40 amps. Surely each fan (they are relayed and fused individually) is not drawing more than 30 amps. If contact pitting/sticking is a problem, I guess we could put suppressors on each one. I don't think that's the case, because no one else is having problems like this with the powerblock and electric fans, and we've sold hundreds of them. The first two cars I wired with the powerblock kits and electric fans have been on the road 12 years now, with no problems.

For troubleshooting, remember that the Driver's side fan relay is on the fender well under the hood, and the passenger's side is on the power block. Fuses for both are on the power block. Someone suggested that maybe engine bay heat is the culprit, but it's the driver's side relay that's under the hood, and it was the passenger's side fan that was running (maybe both of them would have been if the circuit breaker for the driver's side hadn't fallen out of the fuse block.

You got me! I'm pretty sure it's not a design problem or an installation problem, as it would show up all the time if it were. As far as I know, it has worked fine most of the time, with this time and the time in Texas being the problems we've had. If it happens again, before doing anything else pull the B/G wires from the switch and see what happens. If the fans go off, it's the switch; if not, it's somewhere else.

Max, could you cut the offending relay open and see if the points are badly pitted? I don't think we have done that yet and it seems that would be the best way to know for sure. This seems to have been a problem that we've had off and on pretty much from the beginning, not just in Texas but also on the Power Tour. Maybe that suppressor is a good idea. Is it possible that the inrush current is much higher and causing the points to burn and stick?

Jim

Dan/JIm:

2 years ago when we had the car and were getting it started (and I reported some overheating issues) it was because both fans were on the same relay AND fuse and this 20A fuse was blowing (likely on start up of the fans.)

I did a current draw check and found the fans wanted 26A when they were triggered! I called Carrick, got approval, and put in a 30A fuse. I believe this was also a problem (?) and then last I heard Dan had added in the separate relay and moved it to the fender area, and separated the fans on the fuse block.

IS THIS still that original relay? In which case, if it had to deal with the firing of BOTH fans at one time in it's life, then we should probably change it and open up the one that was there and check for the pitting issue.

When we jump started the RM yesterday I readjusted the fan switch for a slightly higher temp (190F). The fans were running-- they went off. Thus, IF the switch is having a problem, it, too, is tempermental. I have 3 times moved that switch and only this time when the fans were still running on a cold car did it NOT obey the rheostat. (I wish that I'd stuck that circuit breaker back in and then seen if BOTH fans ran. That might have given us a better clue. At the time, I didn't even know it had fallen out of the socket.)

I would presume, given that it's NOT the right fuse that Dan set up, that it had blown sometime during the power tour or texas. Does anyone know about this and what were the reasons for it?

I'm driving the car Thursday to show to Rob Edwards (who had helped do the wiring and is listed on the hatch glass.) We'll have an hour lunch-- I'll see if the fan still runs when I get back, etc.

Thx for the info, Dan.

M