Turbo on an MGB engine?

I was going to post my question on the straight up MGB & GT forum, but thought that there might be a bit more info on this side.

I've been working with turbos for the air cooled VW engine, pretty good luck mixing and matching "back yard" parts, and was wondering if anyone knew how the MGB engine responded to turbo charging? It seems like a pretty good candidate, there are several aftermarket Weber manifolds that could be adapted to work with the plumbing pretty well, tube headers are easily had, distributor is similar to the VW Bosch in it's workings and will accept the Pertronix module, etc.

I was wondering about the strength of the bottom end, pistons and such.

I'd love to poke around a bit, I've got extra parts to work with, a few appropriately sized turbos, and there sure seems to be enough room to fit everything, especially if I remove the heater fan/box.

Any help at all would be appreciated.

Thanks,

TC

Sounds interesting. I was thinking about turbocharging the 66 bug. I think the smarter guys here will say the bottom end of B motor is quite strong. Heat might be the problem with the carbs and exhaust manifold so close.

We had a local club member did one years ago. Used a Ford Escort turbo with a Harley CV carb. Ran great.

I was thinking that I might mount the turbo on the heater shelf, then run a nice stainless tube with urethane couplers to a "hat" mounted to the top of an aftermarket Weber progressive two barrel manifold. This would make for a nice clean and isolated turbo mounting and air/fuel inlet to the engine.

The carb for the turbo could be either a 1.75"/2" SU or a Weber DCOE. The turbo would probably be one of the KKK Audi turbos with an internal vacuum/boost regulated waste gate, nice and simple. An old four tube header running down to a collector, then a single pipe under the engine where the engine and trans join and back up against the firewall to the heater shelf/turbo ought to be fairly straight forward and simple. The final exhaust from the turbo would run back down the firewall through a few bends and out the back of the car. With the usual chop from the turbo and such a long pipe, there's no need for a muffler.

The oil for lubrication would be tapped at the brass fitting for the oil pressure gauge and returned to the sump or an angled fitting at the lifter side cover. Distributor would be locked, as is traditionally done with the VW engines, and a Pertronix ignition module installed. A boost referenced fuel pressure regulator, especially considering the small bowl on the SU carbs, would be simple and easy. Possibly a boost sensitive water/alcohol intake manifold injection set-up as well to cool things down. Simple to make one, fill with Winter formula windshield washer fluid and done.

Otherwise, this set-up would be as simple as installing a sink, as long as the bottom end can take it and the compression isn't too high, it should be a neat little power booster and as cheap and easy as can be to make and install.

Just sorta wondering if anyone's done it and what they ran into while doing it. Again, I've never played with an MGB engine, but have a lot of experience with back-yard turbos on other engines. Not at a professional level, and none really larger than around 1,900cc or so, but it sounds like a fun project that I could handle if I could get a bit of prior knowledge before blundering on in.

Thanks,

TC

Sounds really cool. Todd Budde did it on a B engine. Apparently it ran fine but he ended up blowing up his engine when he ran too much boost.

I don't know much about it, but you could ask him. Anyway, here was his setup. Scroll down to the bottom to see the MGB engine:

http://www.britishv8.org/MG/ToddBudde.htm

Hi!
I have turbocharged some B's with great results and it is really easy to do it.
I have one exhaust manifold available for sale.

There was a fellow a number of years back that I think post here about his turbo'ed MGB GT in Hawaii. he used a Marina intake manifold split from the exhaust manifold if memory serves. The power was not enough as I believe he planned to go for a GM 2.8L V6 conversion which is the lowest standard BHP GM V6 conversion at 110 bhp and 140 lbs tq in stock form- more with a few mods. which would have been more power than he could produce.

Will it do more than the standard motor? Yes. The MG Metro Turbo produced 95 BHP I believe.

-BMC.

There was a extreme build thread on a MG Motor to see what the real max power it could produce. Where they took a MG 1.8l up to 160 hp not sure of the torque number. I can not remember if it was a turbo or the normal SC, but they went over every inch of the engine to maximize air flow.

I tried to search but could not find the thread. Maybe someone here will have it bookmarked.

This was one reason I came to the dark side. (:D If they had to pay for all the labor that went into that build, $10,000 would be on the low side. So I set my budget at that number and looked at what I could buy for that amount.

A 3.4l V6 stock has same hp and is a lot less the 10K!

On the other side, there is something to be said in going down the road less traveled! It's your car, make it YOUR CAR. >:D<

Charles,

I know what it takes to build a 1950cc engine, I know what it takes to build a SC MGB motor. Combine the two and you are certainly over $10K. Add to that a 5 speed and now your ever more running the numbers up.

Now to get the proper power to 160 BHP (and probably 130 lbs Tq) at the flywheel, your going to need tuning time and this is a carb which means anything will upset it and fuel economy is going to be somewhere in the lower 20s or higher teens.

If I did that much to many of the conversion engines with fuel injection, my $$ numbers will be lower, my BHP/Tq numbers will be higher, my drivability at low speed will be better, oh, my higher speed driving will be better as well and the fuel economy will blow the Austin B series out of the water.

Now if i want original- I'll stick with the B series Austin (it's NOT originally an MG motor!!!) motor. I enjoy working on, playing with and driving A and B series motors but they have limits- like everything man made does.

-BMC.

Found this on eBay:

http://www.ebay.com/itm/110714387218?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648

Looks like it might be good for my stupid experiment, if I get it, then I won't have to break up the Weber Progressive kit.


"I have one exhaust manifold available for sale."

Photos and a price would be nice, if you have the time.

Thanks !

TC

I love force induction. Force induction has its place and a 1.8 MGB I4 is not the place. Maybe, just maybe with a crossflow head. Then is the issue of reliability.

If it is a most to do, consider the smallest Garret turbo GTX4294R which is used on motorcycles. The same power can be achieved with an engine swap with more reliability.

I have a build thread in the midget forum using a Suzuki Hayabusa (motorcycle) engine/trans assembly and turbocharging it. Less weight, WAY more power, and a 6 speed transmission.

Yes you are right. the # was in my head since it is going on a friends V8.
But you get the idea.

Do you have a link to your project Ian? Sounds great!

Thousands of Chrysler 2.2 K car turbo's in wrecking yards. Probably about right size for MGB. There is a company that has rebuild kits for turbo's.

SAAB turbos with cooler

In response to Brians comment about the Gt here in hawaii. Mark actually made 168hp to the wheels of the stock B motor. Ive been told he had given some STIs a run for their money on the freeways, but engine reliability was certainly an issue. If you do decide to turbo the stock motor, be sure to have a nice reserve of motors on hand, cause you will be blowing things up from time to time! I personally would opt for a motor swap. Its a lot of work, but worth it in the end! No matter how fast your car goes, if you can't enjoy it every time you get in it, its not so much fun anymore! Save your frustration, swap an SR20 or CA18 motor! More bang for the buck, and it definitely has a bigger WOW factor!!

I encourage you to try so that I can learn from your mistakes! :)

I've been looking at this as well. There are a few leaders on the B-series engine world (like Luis) but the best experience is actually for the similar A-series Mini engines. A lot of people doing it there.

Here are the issues so far that I've uncovered:

1) Fueling. Turbos get hot, much hotter than superchargers. You really don't want fuel-laden charge going through the turbo, so the fuel should go in after pressurization. Because carbs are generally not designed for positive pressure, you will likely need to go with fuel injection and a sealed throttle body.

2) Knock/detonation #1. It sure would be nice to protect the engine with some sort of knock detection. The MGB engine is noisy, so classic microphone-based knock detection is tough I imagine.

3) Knock/detonation #2. Ignition timing should ideally be retarded once you get into boost to protect the engine against detonation. Distributors can't really do this, so think electronic ignition with some sort of boost retard functionality.

3) Knock/detonation #3. Another way to prevent knock is to dump more fuel in during high boost. Another vote for fuel injection.

4) Knock/detonation #4. Another way to prevent knock is to avoid transient overboost conditions. Think boost control valves, tied to the ECU even better.

If I were to do this, and I'm thinking hard about it, here would be my plan:

- Downdraft Weber intake manifold adapted to some throttle body.
- Throttle body injection with a wet manifold to reduce charge-stealing behavior with the Siamese intake ports.
- Small turbo, something like a GT17 or GT25, for quick spool-up but less chance to grenade the engine
- Electronic ignition
- Electronic boost control valve to protect against overboost

I'm looking at the Saab Trionic 5 ECU. Using the Saab coil pack ("Direct Ignition Cassette"), this combination can detect knock conditions using the spark plug as a sensor, and automatically dial back boost and retard ignition in real time. Fully tunable as well. It does require a 60-2 crank trigger wheel (but does not need a cam position sensor).

-Tim

1 - yes, you can have the turbo suck through a carb. It works quite well, but you need to pay special attention to shielding the float and carb (and may have to mount on an isulated extender to get the right effect).

2 - 4 - I solve this on my race car using a knock sensor and a cockpit adjustable timing control. MSD has all the necessary bits available. Save yourself a lot of trouble and expense and use a 1 3/4" HS6 SU

I am running a turbo on a Mustang 2.3. Mine pretty modified. I would think highly on EFI, with a wideband air/fuel ratio meter so can datalog info and change, I would think of a standalone system. Megasquirt is one comes to my mind. Speed density is probably easiest way to go. [MAF system have problem with back flow of air after throttle body shuts off]Intercooler air to air or maybe water to air. [water to air has less charge air and can run a small water radiator in front of B one.
http://www.megasquirt.info/
Need to lower compression ratio, forged pistons,
I presently run 15psi, 38lb injectors, I run a stock turbocoupe computer.
If can use a Ford EFI distributor and TFI. Could run a turbocoupe computer setup,
My setup.
http://i177.photobucket.com/albums/w224/mgman75/mgmidget006.jpg
This how my firstup started.
http://i177.photobucket.com/albums/w224/mgman75/100_4654_0001.jpg
Here is site where a guy turbo'd a Midget.
http://81.149.250.214:76/Inject.htm
Showed how he did the fuel injectors etc. Maybe give you some ideas. Good luck sound like interesting project. Maurice

This is NOT a low budget installation..
EFI, aftermarket internals, crossflow, 200ft/pound of torque at less than 5k rpm

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Dann Wade. Just curious what was the airfuel ratio on motor with blown pistons, compression ratio, did it have oil squiters [to cool pistons]. What did the datalog say. Was pistons forged if not about 4 to 6psi is as general rule is about it. Fuel pump specs. I run 255 HP?HV pump. Lean and too much boost will take out pistons. I know I ran 20psi on mine with 38lb injectors. I took out the top of pistons.
Note on Luis Rodriquez setup. His setup on the B is way past mine on the 2.3 turbo Mustang. Note EFI, I assume speed density tuning [No Maf or Vam meter], blow off valve, piping to front for intercooler, Looks like catchcan for blowby. Cogged belts on front unsure what he is driving. Would love to know. Major bucks. Nice and thanks for sharing. Maurice
Edit I can't argue. Turboing a B would probably be more expensive. Lot of custom parts. But a turbo is a blast. Maurice

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I was just curious. Sounds like a real good setup of that time. I know Ford tried carb turbo and it wasn't too good. [Lot have converted to EFI]. I know I melt my pistons with too much boost on my Ford. Turbo is nice but if having to engineer your own system can be real expensive and still lot of experiment and failure. Sound like you went the proper way. Thanks for answering my question. Maurice

My take on this conversation:

Turbocharging by itself is not an issue - Moss has proven with the supercharger kit that decent performance improvement can be had with sensible boost levels, and boost is boost.

But unlike a supercharger, it's easy to get boost-happy and blow up an engine with a turbo. If you are looking for 200HP and 200 ft-lbs you had better know what you are doing and plan on not getting it right until the fourth engine. Nobody gets to the fourth engine because by that time they've given up and dropped a V6 in.

So there's nothing inherently bad about turbocharging a B engine. The Mini turbo guys have been strapping turbos to their engines for a long time and generally have things worked out. They know what boost they can do at what compression ratios, how to prep the engine, keep the A/F and detonation in line, fuel inject with siamese ports, etc. And in the end it looks a lot like the Moss supercharger: 5-10 psi boost (depending on CR) using small T2 turbos, well under 150HP.

And maybe the only reason that it is better developed for the Mini is because those guys generally can't swap engines. If they could, they would.

If your goals are modest (additional 20-40 HP) and your budget is somewhere between a $1200 cross-flow head and a $3000+ Moss supercharger or engine swap (not counting your time and fabrication skill), then a turbo might play a role in your future.

Midget 1275 is easier. In Uk there is turbo Metro already done. Lot of site with that setup. Going on a MGB that is pretty well start from scratch. That can get interesting and expensive. Maurice

Wonder if it would clear the hood. These motors are solid, easily built up power wise and generally cheap to find. I've been searching on this the last few days lol.

I had found the bellhousing shop yesterday thanks for the link I forgot to book mark it. That takes care of one of the big hurtles on this one. Did some quick looking on car-parts.com and found a few 4 cyl T-5's in my area for around $350 and a couple of the proper year range Saab's for a donor for under $800. Figuring out the ancillaries would be fairly easy and a front mount inter-cooler. The cross member wouldn't be to bad to figure out looking at the dimensions on the motor. I wonder if classic conversions sells the tranny mount for the T-5 separately.

I think I have completely hijacked this thread now.

saab b234L + adapter plate + bmw m20 gearbox, this is the way, I have the picture to make the adapter plate if you're interested.
That will be the way I do when I finish a couple of projects I have in progress.
AHHHHH I have an ecu also modified to 230 hp.
Cheap swap¡¡:D

would there actually be a benefit to running the BMW transmission over the ford? Cost wise it's Ford all the way and I know it's a solid reliable transmission.

Your probably right on the European availability.

Going to look at a 96 Saab 900 tomorrow :D