MGB & GT Forum

I'm just askin'.

Stock motor. Get quality parts and machine work.

And add a supercharger!

---

John Moore

'70 MGB, '68 MGBGT, '99 Land Rover Discovery II, '61 Austin Healey Bugeye Sprite

My preference, keeping the MG 1800:
Burgess street/econo head on the 72 big valve, 9.5:1cr or so. Stock cam
Megasquirt wet manifold TBI on a Cannon manifold
Wasted spark ignition
Nissan 5 speed
Alternator, positive engagement starter, TR7 disk.


Now, if you just want an 1800...
Toyota 18RG twin cam, Megasquirt et. al.

These are my ideas of an ideal street MG. I am sure others will go on for 40 or so posts telling how EFI is immoral and kills baby seals.

---

Cogito ergo sum periculoso

I bought a Mgb because I like the old fashioned parts like the SUcarbs, points and original fuel pump and shocks.
If I wanted a modern sports car I would buy a Z06 Corvette or a 993
Porsche.

"How to build the ultimate MGB 1800 engine for a daily driver?"
Daily driver or constant fiddling and less driving?

Mine's simple (OD + Schlemmerized), ZS, and drives great with simple maintenance.

For the most bang for low bucks beyond stock do the following:

.060 overbore
Balance rotating assemblies/take some meat off the 3 main flywheel
Stock or one stage up cam
Have head ported by an experienced machinist
Have Jeff Schlemmer overhaul distributor
Have Dave Braun revamp the SUs

3 main Bs are the best revving anyway, and the overbore really helps mid range power.

The above is basically what my iris 62 has and it is one quick little street B that will idle at 650rpm. I've done a bunch to these specs and unless you really spend a lot of money this works.

Good advice guys, just what I need. Anthony mine is a post october 64 so is 5 main but I expect the formula is the same. John, I like the idea that if I build a solid and reliable motor SC'ing is an option down the road.

That's exactly what I did! Have fun building your engine.

---

John Moore

'70 MGB, '68 MGBGT, '99 Land Rover Discovery II, '61 Austin Healey Bugeye Sprite

This is a great thread idea but I am also interested in improved performance. So what sort of horsepower/torque increase is reasonable for an MGB 1800 naturally aspirated, streetable and reliable?

And how do you get there in terms of build?

Basically it has to breath more air, compress it tighter and evacuate it efficiently.

Ideas?

---

The goal - Reliable summer driver interspersed with mechanical tinkering...
Motto - "Driving fifty in the twisties..."
On Mods - It's your damn car - Do what you want. Haters gonna hate...
On SUVs - Drive your B like a soccer mom is texting her friends about how she wants to kill you...
Red Betty - http://www.mgexp.com/registry/GHN5UH418165
Bart - http://www.mgexp.com/registry/GHD4U146898G

With the 5-main, you have some other options in addition. Change the rods, pushrods, and lifters out for the 18v style. The 18v pushrods are longer and the lifters are shorter, hence less weight riding on your cam. The 18v rods are lighter also than the stock earlies.

Dan get a good head.
Peter Burgess calls his Econotune. Dave Headley call his street head a 80-20.
Get a good line hone and get the block milled to square it up.
A critical item that often gets overlooked is the fit of the distributor drive gear.
You want to be able to maintain consistent timing numbers.
If the gear fit is sloppy the timing moves around.
Spend some time and get the compression ratio figured out by measuring the combustion chambers and how far the pistons are down in the hole. Don't push the compression ratio to high. Keep it low enough to you can run a lot of advance.
Pay attention to cam timing.
Get it dyno'd after it is broken in.

Here I did two of them back to back, one was for Dennis Johnson in Alaska, then one for my car, which I have since traded for a vintage racing MGB. There were 1900cc engine, which we used special order .080" over pistons, that might be the only thing I would change, the .060 Piston are less than 200.00, the .080 piston were more like 450.00. In retrospect I think the .060 over piston are a better budget choice and the extra .020" over wasn't good for much more HP. The engine made 125+ HP, are completely streetable, my ex car has probably has close to 20K mile on it since I built it. The new owner drives it to work several days each week, I also did the T9 5 speed for highway cruising . My goal with these builds were to get to stockish engine with a supercharger HP, and cost considerably less, since I was not buying a $4000 supercharge, and have a cleaner, less fussy engine bay,and easier car to work on.


It's a long read, but lots fo good stuff in there, and some stupid stuff in the thread.

http://www.mgexp.com/phorum/read.php?1,1814529


OH and I getting ready to build a similar engine to this in .060" this fall. I will document it here when I do.

---

Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com

I suggest you take the time to read the Burgess book. I expect those who have had great success above did so before they spec's their engines.

If you must have lots more power, put on the blower or put in a 3.4 V6. The later being probably much cheaper than even building a sweet 1800.

---

Cogito ergo sum periculoso

Rather than just opening a catalog and ordering parts, work with one of the smaller vendors to get the most for your money and have a more reliable/better setup. There are several, I was very happy with the results.

All in, I was just over the $3k range with me doing the pull, disassembly, assembly and install. It could be done for less money, I didn't skimp on much.

It's definitely a full winter's project. I started in November and finished late February.