340 upgrade

[BlownMGB-V8]

In anticipation of the new wheels coming in I've been doing a little math on the weights. Based on dimensions only, and with the old Centerline wheels weighing in at 11.9 lbs each, the newer larger and wider wheels should come in somewhere close to 21.2 lbs rear and 16.3 lbs front. This isn't as bad as it might seem because the new tires are lighter than might be expected. On the front, depending on the tire I end up with I'll have a +1 or +3 lb increase in unsprung weight at 41 or 43 lbs, 41 most likely. When I do the brake upgrade I expect to drop at least 7 pounds at each front corner, so in the end I think unsprung weight will be below stock, maybe significantly so. More on this later.

Does anyone have the weight of the stock wire wheel and tire, or the stock steel wheel and tire? I may have a caliper and rotor I can weigh, at least the rotor. Not sure about the caliper.

On the rear it's a different story entirely. I pick up about 10 lbs with each wheel if my calculations match the new wheels. The new tires are about 1/4 lb lighter. But I drop considerably more than that with the inboard brakes and independent suspension. I don't remember now what it comes out at, I'd have to look back through this thread to find it. But based entirely on my faulty memory, it seems to me there was something like a 40 lb per side improvement which would translate to a 30 lb decrease even with the heavier wheels.

I think I'm gonna like this.

JB

[Jim Stabe]

Jim

If it's any help the weights on my 17" ZR1 clones are 20# for the 11" and 18# for the 9.5"

[Dan B]

Harry and Pat's glider did look good though after it was finished.  I can't remember what I got out of the deal from Harry...maybe the Konis, but he made up for it on the TR6 and OD.

[BlownMGB-V8]

Bet it made yer eyes cross after awhile, didn't it?

Thankfully I'm about to finish up. Put some fresh sand in tomorrow, hit a few spots, give it all a final blast and paint it. Move on to baking.

I discovered one more little trick that really helped. I had a 2.3" port in the back of the cabinet that was sealed up with a plug so I opened that up and  ran a chunk of PVC pipe about 4 ft long and an elbow into it with the pipe pointing straight up. That gave me more airflow through the cabinet without any dust getting out. It didn't get rid of all the fog but it helped tremendously and got rid of a lot more of the dust.

I'll tell you what. After all this I can understand the rust. These are pretty long headers. 38 inches in the primary tubes. It's a little tricky getting around them in the cabinet and some spots are definitely difficult. If the guy was using the same size cabinet I doubt he came out on the price. Of course it's still way easier to do the job right than it is to do it over, but I can understand.

JB

[BlownMGB-V8]

Anything truly worth doing is worth doing twice. If it isn't you'd better be asking yourself if it is worth doing the first time. Often the wiser course is to pay someone else to do the job for you.

But having said that, there is much to be gained by the experience of trying something new. I personally take great pride in being capable of doing the job right and to my own satisfaction the first time around, regardless of the technological challenges and most times my confidence is proven right. I've been doing this type of work long enough now that I almost always am aware of the blind corners before it becomes too late. But, and this is a very big butt, I am never afraid to back up and disassemble if I discover something that I don't like. This is where doing it twice comes in, and as I always keep that thought in mind, I may begrudge the extra labor but I never feel it is unexpected. That is a major plus in a project like these headers.

So. After all of the work required to remove the old coating, including necessary upgrades to the blaster cabinet brought about by weakness in the system revealed by the heavy use, and setting up the oven,I finally was able to coat and bake the headers. YAY! Except that this water based ceramic coating isn't the easiest stuff to master and the coating was a bit heavy on the first one. When It came out of the oven it looked like a boiled egg after you crack it and roll it all around the tabletop. That was followed by a couple days of shaving the new coating off with an old carbon steel butcher knife, a couple more days of yet more upgrades to the blast cabinet, and now finally I am blasting off the last vestiges of the new coating. Should finish that up in another day or so and then there are flaws in the other header which need blasted and re-coated which were caused by mis-handling. It's pretty delicate stuff until it is baked.

If ever there was a job that merited the adage above this was it. Am I glad I did it? Yep. The headers will look much better, I have a new skill, and besides, I could never have afforded the initial cleanup to remove the old coating if I had hired it out. Many, many, many hours of shop time were required to get the old ceramic off. Plus later if any touch-up is needed I can do that quite easily. Would I consider coating headers for someone else? Maybe. It's pretty labor intensive, but for new pipes wouldn't be too bad. I think a lot depends on whether I build the vibratory polisher as that is yet another labor intensive part of the job. Once the pipes meet my satisfaction we'll see about that. It WOULD be handy to have the machine, and not just for polishing headers.

Meanwhile, my new wheels are supposed to come in today. Can't wait. But I have to I guess. Photos soon!

JB

[BlownMGB-V8]

[Bill Young]

That's really looking good Jim. I look forward to seeing the car up and running. I came along late to the group and you towed the Roadmaster up to Wisconsin the first year I made the meet and then the engine died soon after that.

[Dan B]

It's coming together really nice!

[BlownMGB-V8]

Thanks guys. This time I expect to be pretty much done with upgrades except maybe some stuff like the dashboard and A/C. It'll be time to start putting the miles on again.

Weighed the wheels, 20.5 rear, 3/4 of a lb lighter than expected. Front is 18.1, 2.2 lbs heavier than expected but that was before going to the high pad design which had to add some weight. Those are some really stout center spiders, they look really strong. Plus there is room for any brake package I could want. Here are a couple shots of the wheels and tires. That measuring stick is 12" long. The tire shown with the front wheel is actually a little smaller than what I have in mind for it. That's a 225/45-17 and I expect to go with the 255/45-17, but these will work for now.





Here's an elevated shot of the front. Sorta looks like it means business, don't it?



JB

[BlownMGB-V8]

Now I know what you're thinking: There's no way that much rubber is going to fit under an MGB. Right?





I'd have jacked the tire up higher but the coil-over was wanting to lift the body.

JB

[rficalora]

It looks great Jim!  Did you do some rocker work too?  Don't recall you mentioning it but looks like new metal in the last pic.

[Jim Stabe]

Take some pictures of the whole car on the ground. I want to see what it looks like with the flared rocker panels and the big tires.

[BlownMGB-V8]

Jim, this is the best I can do right now, still waiting on new front tires and other things. Car still looks a little high as I couldn't roll it to let the suspension settle.

Rob, that's all old metalwork, nothing new there. New paint isn't on the schedule for another couple years, although it does need it.

The rockers date back to the early 80's but were upgraded with perforated stainless to help cool the mufflers about 15 years back. But bodywork is not my strong suit. There are plenty of flaws.

JB

[BlownMGB-V8]

I've met with some success on the header re-coating process and now have 1 header with a good coating of cermachrome ceramic, ready for the polishing step. I'm in the process of stripping the other one again for re-coat and after initial work with blade and blaster have opted to try a chemical strip. Using first oven cleaner and then liquid draino (lye) the coating is slowly being eaten away. I'll see how it looks in the morning.

Anyway, I also have a pair of tires for the front on their way but they are back ordered. Hopefully they will ship soon. I went with the 255/45-17s. Not sure exactly how they will fit, but it's going to be close on the inside. I can justify temporary spacers on these though to move them out if I need to, because the planned brake upgrade will be using slip on rotors which should move the flange out about 1/4" anyway. A little fine tuning could be necessary, maybe a bump in the fenderwell or a spacer under the bump stop. I'll have a lot better idea once the tires are mounted. That will also let me know what the car's stance will look like and help me decide how much I need to "bend" the car.

That probably struck you as a funny statement. It should. But allow me to explain. This car has had a rough history. It was a dirt track racer in southern W.Va. (a very rough neighborhood in case you didn't know) and then, after the usual rust attacks, permanently became an experimental vehicle. Along the way a sill replacement was done, but without benefit of the mandatory temporary bracing, the result of which is a sag wherein the center of the car is somewhat higher than the ends. This causes all manner of problems, the most obvious of which are gaps at the windshield and poor door alignment, but it also causes the radiator support to sit lower than it should. The proper repair involves yet another sill replacement which, if you've noticed the rockers, is a bit more of a custom job than the standard repair. So I've come up with a possible solution, but one which is not without risk. I propose to "bend" the car straight. This is to be done by using the 2 post lift as a very large hydraulic press. The idea is to position a beam through the door openings, chain it to the floor on both sides, position blocking to apply force to the selected area of the sill being bent, and then bump the lift up to force the sill down. Will it work? I haven't a clue. But if it does I'll be able to close the gaps and align the doors. And what's the worst that can happen? (OK, maybe I shouldn't even be asking that question. Maybe I should go ahead and order replacement panels. Maybe it's a good thing I have a spare car sitting in the shed.)

I don't know at what point I will attempt this insanity. Sooner than later if I don't like the stance of the car on it's new tires. Or I may wait until I've driven it a bit. We'll see.

JB

[BlownMGB-V8]

Sitting on it's own wheels again finally. The car sits a little high right now, it still has 60 psi in the tires and the suspension needs adjusted down, but that's pretty easy with the coil-overs in the rear and the air bags in the front. Front air bag pressure is at 90 psi which is 10-20 psi high.



After the car is back on the road I will probably look into replacing the rear coil-overs with air shocks in order to get air suspension all the way around, but the real trick will be if I can get the same air pressures front and rear. That's doubtful but possible. We'll see. It would be nice to be able to raise and lower the entire car at the touch of a button.



Still sand blasting the second header. If anyone ever tells you this is easy, smack 'em for me! So maybe by a week from now I'll be ready to polish those and I hear that job is real labor intensive. Just the sort of thing I was looking forward to. Incidentally, Techline does have a header coating they say is almost as good which doesn't require polishing or baking. (I think baking it would still be a good idea.) I might consider putting some of that on the MG-Roadmaster's headers sometime.

Looking forward... Driveshaft, shifter, A/C compressor, accessory drive, double condensers, fuel rails, air inlet/throttle body, intercooler plumbing, along with various and sundry small details. This might take awhile.

JB

[BlownMGB-V8]

I found a way to put off building a vibratory polisher to shine up the headers. The labor was one thing, but the ceramic tumbling media was going to cost a couple grand, I don't have that kind of money to spend on it, and pea gravel wasn't looking like an acceptable substitute. So I found a shop that would polish them for me and shipped them off. Hopefully they'll be back next week sometime. In the meantime I've begun work on the inlet scoop. The IAC valve isn't going to work very well on the downstream side of the blower so I pulled that off and will make a blanking plate to replace it, and will locate the IAC on the bottom of the scoop between the butterflies and the air filter. The large pcv breather line will go there as well from the Lucas flame trap, and if I decide I want a throttle blip valve there will be enough room left there for it as well. It's looking like the three butterflies will be very close to 2-1/2" diameter which is pretty big in terms of airflow but visually about right and proportional to the rest of the scoop and the blower. If low throttle openings give me trouble I may have to play with the linkage to get less movement with the first part of the pedal travel.

I will almost assuredly have to cut the hood again. Maybe that won't be too bad though. After the nice way the opening in the Roadmaster's hood came out I think I can do a little better on the edge treatment.

Anyway, I have the bottom of the scoop cut out and bolted to the inlet with a spacer and I've found how to make nice clean large radius bends in the 1/8" aluminum sheet I'm using for it so now I'm just waiting on more supplies to come in. I'll try to get some photos.

JB

[BlownMGB-V8]

[rficalora]

Menacing.  I almost didn't notice the headers.  Looks like they polished out very nicely.  Too bad most of them are hidden by the fenders.

[BlownMGB-V8]

Actually Rob, they are not. You're forgetting it's a tilt front end, so when the hood is open it looks about like what you see there.

The headers came out very nice. The place I sent them to did a really good job polishing them and was fair on the price at $50. The shipping ate me up though, $75 there and $55 coming back. (10 of the 75 was insurance) But these always were expensive headers. When I first built them I had $750 in the headers and header mufflers. This time around I couldn't even say but it's probably less than that and I have other things to show for it like the oven and blaster upgrades as well as a new skill so it wasn't that bad. You can see the age in them though. Pockmarks from old rust, tool marks from cleaning, etc. They have character. But I hope the coating will last longer than the last time. If it does I won't have to worry about the next time around.

One thing I did was to install bungs for individual EGT sensors. But the sensors themselves are about $55 each so they won't get installed right away. I think they are a good idea, but buying wheels put them off the radar for awhile. Gotta have wheels though, if it don't roll it can't go anywhere. These headers are 1-1/2" diameter long tube (38") equal length within 1/8" on all 8 tubes and they really lit a fire under my high revving Buick 215 and the blown  Olds 215. I built them expecting to end up with a 5L BOPR but I think they will do just fine on the 340. I cannot overemphasize the benefit of equal length tubes. I know our MGBs don't have room for them but they really wake the engine up.

Menacing... That's a word I'd never thought of but now that you mention it the new scoop does sort of convey that character just based on its size. Really it doesn't look quite that big in real life. I don't know if that will change when the throttle body goes on and with the rest of it boxed in. I have several more significant challenges in finishing it and I'm flying by the seat of the pants but it's coming out pretty good so far. The challenge is making it look good and also work right. But I'm pretty confident of success. One critical part fell into place today, a domed aluminum weld cap which will provide the transition pieces at the upper rear corners. Some trickiness with the filter tray and some lower radius transition pieces and then a bunch of welding, clean up and polishing. The throttle body is an entirely different challenge. If anyone is interested I can take some construction photos of the scoop. I was inspired by Gary Walker's work on the surge tank for the MG-Roadmaster to try some new tricks and up my game and I think it is going to pay off. You know, there are tasks that you do in which you try to work quickly and get done, and then there are some fairly rare opportunities when you take your time, work deliberately and carefully and create artworks. This is one of those opportunities and I'm trying my best to make the most of it.

JB

[BlownMGB-V8]

Here's what I've been working on during the last couple of weeks:







Still have to make the throttle body to go on the front, and the housing needs polished and buffed, but functionally it is complete except for the breather tube fitting. The air filter is a modified K&N for a SBC if I remember correctly, and the IAC valve will mount to a block on the underside. I still have to make an inlet screen for the block.

JB

[DiDueColpi]

Looking real nice Jim!
How do you change the air filter?
Cheers
Fred

[cgill]

I think you might have created a bit of a blind spot with that blower!

Seriously, amazing fabrication work Jim. Keep the pictures coming. I can't wait to hear it.

[BlownMGB-V8]

Thanks for the kind words.
I can actually see over it so the blind spot is only right in front of the car on the right side, not as bad as it might seem.  It's a little taller than the old one (in my avitar) but I honestly never even noticed that one at all. We'll see how it looks when the front end goes back on the car. To clean the filter I just pull down and forward on the frame below the filter (just takes a gentle tug) and then the filter drops out. The throttle body will have a pair of tapered prongs attached to the back side which will wedge the frame upwards to seat it when the TB is attached. Getting that piece made is my winter project this year. There's quite a bit of trickery that goes into the TB and it won't be fast or easy, but at least it'll be the second time through this time and I have a few new things to try. For one, I am going to make the butterflies this time instead of cannibalizing an old carb base. Then I am going to use a pair of bellcranks along with heim joints and polished stainless rod to actuate the shaft and this will let me configure the linkage to get maximum pedal movement at minimum throttle openings and vice-versa. I may even put the TPS on the lower bellcrank if I can get all the play out of the linkage as it would look cleaner and get the same proportional advantage as the gas pedal.

But for now I have polishing and buffing to do, any tips gratefully accepted. Not just the housing but also my stringers for the inner fenders which are stainless and more than a little tedious to buff. I have to get those done next though because they are holding me up on my plans to bend the car, which has to be done before I can hook up the header mufflers. So at this point it's all pretty much brainless labor for awhile. Which is actually a good thing because I'm not up for any more big challenges until I get time to recharge. Maybe sometime between Thanksgiving and Christmas I can get back on the more demanding stuff.

JB

[BlownMGB-V8]

Much closer now. All the major components are in place and it looks pretty complete. Today was a big day for me.



The scoop and stringers are nicely polished and installed. Not perfect, but I was always more interested in results than appearance anyway.



This is the third major build for this car and finally, I am completing the car I've always wanted. There is really nothing on the car I would change even if time and money were no object. Well, maybe spruce up the interior and paint a little, but it's very comfortable the way it is so maybe not. Maybe run the exhaust out the rear and do the planned upgrade on the brakes sometime but those are pretty minor compared to all the rest. I'm really looking forward to driving this car.

Still a lot of smaller jobs to do, and one very particular milling job. But the worst is behind me now.

JB

[BlownMGB-V8]

Today I managed to cut out the blanks to make the throttle plates. That job was sandwiched in between making upgrade parts for the milling machine. (It's the Blackwood way... fix or make a machine so you can do the job. Usually the fixing takes 3 times what the job does.) Those blanks will be placed into a custom angle jig (yet to be made) and have the edges turned on the lathe so that they match the bores in the throttle body when at a small angle  like any other throttle. It's exacting work, but a good job on that means a nice low idle will be possible. Of course I have to decide which comes first, the plates or the bores. A lot of thought goes into making a throttle body before even the first chips can be made, and parts like shaft bearings have to be on hand before determining final dimensions. Getting ever closer though, the plan is pretty complete.

I also moved the car to the lift, ordered a box of 5/8 x 7" tapcons and found a length of 3 x 3" square tube to run across the sills so hopefully I'll be ready to bend the car in another day or two. I still haven't decided whether to remove the perforated rockers first, but I probably will. I'll probably sink the tapcons tomorrow and set up the rigging, then I have a bunch of very careful measuring and comparing to do before giving it the first shot. It should be very handy having the '74 in the shed for comparison.

JB