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MGB Made a decision, my MGB is going...

Not a fan of 30 over for a road car.
Wondering what your reasoning is. What's done is done on my motor (that's likely the least over they could do, I'm confident this engine has been rebuilt before) but I'm always interested to learn more.
 
Yeah, the MGB block has a lot of "meat" to it. Obviously, the less you need to bore the better; but I believe you're going to be OK with .030.
 
There are many B blocks to be had that can bored at 10 over. There is a lot of metal in the block, but I tend to error on the more the better for sealing and cooling just to name a few. My view would be different if you where going the full job with cam, carbs, flywheel, balancer and cooling system.…..Just my opinion.
 
Only 0.030" oversized bore GB18 engine I took a risk with was one for my brother's '71 MGB-GT. Went with flat top pistons (10.5:1), CC'd the chambers, port-n-polished the head with port matching to a Hooker header & Stebro exhaust, and a manifold with a Weber 40-DCOE. Cammed it with a Crane. The thing would "go sideways at will" in spite of the GT's extra weight. Downside was it needed an auxiliary fan to keep it cool. That was in the days of Sunoco 102 octane. He burned a hole in #3 piston by cheaping out with a lower grade, learned his lesson and I foolishly fixed the problem. He then decided to sell the thing. :mad:

MY lesson was: Don't do work for anyone gratis... I kept the engine and stuffed a standard unit in to replace it.

Didn't mention I'd sprayed it a Lincoln-Mercury burgundy metallic, with the Rostyle wheel's inserts matching. HOURS of work.
 
Sound like a hot road motor. Think about running that set up in the attitude of where drew lives.

You don’t want to ask me about free work, or bartering services……
 
Sound like a hot road motor. Think about running that set up in the attitude of where drew lives.
Fattening up the Weber alone would be a challenge! Cooling it would likely mean aluminum radiator and electric fans. No way now to feed it any octane it'd need either.

You don’t want to ask me about free work, or bartering services……
Seems to be an early lesson, sometimes needing another one for re-enforcement.
 
I always worry about the metal between #2 and #3 - even without overboring it seems pretty thin right there compared to the rest of the block.
Pot #3 in those lumps has always been an issue with heat. The later engines (emission control variety) seemed to be more prone to head cracks and damage on that chamber.
 
Thanks for the thoughts, much appreciated as I'm always learning. This is what it is, it's the original block so I'm willing to take the chance to keep it running in the car. Already running an aluminum radiator and thinking of auxiliary cooling fans anyways. Carbs are the original SUs rebuilt by Hap a couple years ago. Still have to have a final conversation with the shop on the cam and other details, we were waiting to see what the machine shop told us.

It's an interesting journey for sure. I'm much more familiar with the A-series engines, so this is new territory for me. As always, I'll keep y'all updated.
 
Drew,
.030 is fine on an MGB block and I’ve gone as far as .120 over on other engines. IIRC, my MGB is bored .040 over, port and polish, VP12 cam, compression calculated at 9.6:1, aluminum flywheel and lots of other goodies. Hap provided the recipe and rebuild kit and I absolutely love this engine! Very easy to drive in stop and go traffic, keeps up with modern cars, stays cool with the original radiator and fan and requires very little attention. My daughter in law is the caretaker now and she learned to drive a stick and use a choke on this car and it was pretty brutal, but no protests from the B.
Rut
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...to a shop to get it back on the road. (Couldn't resist the clickbait title, it's been a long week -- and a long year. :wall: )

My B has been off the road since I bought it back over 4 years ago (yes, I've bought this same car twice). Engine is really tired, and I was going to put in a spare used engine so I could drive it while rebuilding the original motor. I just haven't been able to make the time to get it done. Working in IT for a public school district during a pandemic has been about what you'd expect. I'm not old, but getting old enough as I barrel down on 50 to appreciate that my supply of years is limited. I want to drive this car and not look at it.

A good friend had his '67 MGB rebuilt by a reputable shop in Scottsdale, AZ recently, and the work was excellent. They did a full engine rebuild and 5-speed swap. Not cheap, but excellent work. It got me thinking, and I decided to haul my car down there as well and get it done.

My B will get engine rebuild, trans rebuild (if needed), and whatever other little things we find. Hope to be driving it before the snow flies. Will likely cost more than I paid for the car to do this, but this car is a keeper and worth it to me. Car goes down there in early June.

I bought this B for the first time in 2011, 10 years ago as of this post. In all that time I've never actually had 2 cars running at the same time. It's about dern time to make that happen, and sometimes that just takes bringing in the professionals.

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You mention a "reputable shop in Scottsdale, AZ " that worked on your car. I have a 1957 Morgan Plus 4, 4 seater that needs work on several levels. I have 2 popped head bolts on the TR4 engine. They will have to be bored out. I also have an awful sound coming from underneath the rear of the car that sounds like metal on metal scrapping. I was a block from my house when it happened, so I drove it home. I don't know if it is the differential or something simple with the brakes. The brakes were ostensibly replaced less than 500 miles ago.

I recently did major damage to my foot (cut 6 tendons and an artery) and have been on the mend for many months. I can barely change a tire much less do major work on my car. I want to fix the car and then sell it.

I am looking for someone who does quality work at a fair price. Got any ideas?
 
We're getting close on the engine, but have run into a bit of a snag sourcing a cam. We're keeping things fairly close to stock for the most part, not looking to go wild with compression or cam timing. Due to supply chain issues we're not finding a bunch of cam options available right now.

We can find a new stock cam, and BPNorthwest has an option available that looked potentially interesting for a mild build:
> British Parts Northwest Camshaft New MGB 65 to 80 Performance KC - Camshaft - Camshaft & Timing Components - 5-Main Engine Components - Engine Main Components - MGB - MG <

Moss is out of stock, and in talking to the builder the cams that APT Fast have available right now are a bit more extreme than we're thinking.

So for a fairly stock engine, stay with stock cam or keep looking? Go with the mild upgrade from BPNorthwest? Something I'm missing?

I'm not looking for max performance, but don't want to miss an easy update while we're in there.
 
Just got a few "sundry" bits from BP Northwest, went thru some of their engine parts when ordering. I've a mild Crane cam in this B, I'd have no reservation about putting BPNw's cam in there, and new lifters and pushrods. 👍

Oh, and the stuff I received (points, rotor, spare throttle cable and a spare brakelight switch) came with a "bite-sized" Twix and Snickers bar! :smile:
 
Thanks, Doc. That's helpful to hear. I'm pretty sure that's the way we're going to go with this engine.
 
We wound up going with that BPNorthwest camshaft -- we're keeping this pretty stock where we can, and given what's available right now this was the best choice for that mission. I'm happy with the recipe. Given how tired this engine was, this is going to be a nice step up.

Engine is mostly assembled, and they're working on doing a bit of engine bay cleanup before it's all back together. We've had a number of delays throughout this project but things seem to be coming together now. I expect things will move right along now.

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Looks great, Drew!

You will be thrilled with the engine performance. You may likely need to do some needle juggling with the SU's.

Good to keep pump gas in mind, I made a bit of a faux pas with the current B; a 40 DCOE Weber and upped compression, along with the cam. Hadn't considered possible octane limitations (It was 1999 ~ early 2000). Only a minor inconvenience but have to plan fuel stops.

But it's quick! :D
 
Tuning it will be interesting. Hap rebuilt the carbs a few years ago and we had it pretty well setup for my altitude (6500' at my house). Will see how it does now with the engine in better health. Still running the stock SUs.

Because of the elevation our octane is a bit lower here. 91 is the best you can find, and if you want ethanol free that's usually 88. So it's a thing to think of, particularly if you're going to travel at all to lower elevation. Most of the good roads around here go up to about 10,000' so I'm usually more concerned about thinner air than thicker.
 
We're making progress! From the shop:

These photos are of prepping the engine bay, priming the engine bay, putting color on the engine bay. We also inspected, resealed and cleaned the four speed over drive gear box. We attached the engine to the transmission and installed into the car.

I'm really glad I decided to get the engine bay painted while they were in there. Wasn't originally going to do that for budget reasons, but ultimately decided to just get it done.

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Looks sweet, Drew! And so much easier than waiting and fighting all the masking of engine, wiring and plumbing later.
 
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