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MGB MGB engine conversion

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I had a friend call me and ask what alternative engines work well in the MGB. Being British myself I am a purist and wouldn't change it - however he does want to. He's considering a Miata engine? But I'm sure there are plenty of other 4 cyls out there. He doesn't want to cramp a V8 into it.
 
SWC said:
I had a friend call me and ask what alternative engines work well in the MGB. Being British myself I am a purist and wouldn't change it - however he does want to. He's considering a Miata engine? But I'm sure there are plenty of other 4 cyls out there. He doesn't want to cramp a V8 into it.
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The 60-degree GM V6 and T5 transmission combo is a great choice. Gobs more power than the B engine, about the same weight, and an easy conversion with lots of support. Here's the one I did a while back: http://www.britishv8.org/MG/MickeyRichaud.htm

Sold it a while back to downsize a bit, but sure do miss it!

Mickey
 
Mickey Richaud said:
The 60-degree GM V6 and T5 transmission combo is a great choice. Gobs more power than the B engine, about the same weight, and an easy conversion with lots of support. Here's the one I did a while back: http://www.britishv8.org/MG/MickeyRichaud.htm

Sold it a while back to downsize a bit, but sure do miss it!

Mickey
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Meant to ask but always forgot; was it necessary to remove the Smith's heater box to fit the V-6? And if so, did you put a heater core in the footwell with the AC unit somehow?
 
DrEntropy said:
Meant to ask but always forgot; was it necessary to remove the Smith's heater box to fit the V-6? And if so, did you put a heater core in the footwell with the AC unit somehow?
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It's not necessary, though it does afford more room for the dizzy. The AC unit I installed included a heater core in the evaporator housing under and behind the dash. A bit tight and fiddly on the installation due to all the hoses, but worked out very well. You can see the "manifold" for the heat and AC hoses upper left in this picture:

MickeyRichaud-BB.jpg
 
Mickey Richaud said:
It's not necessary, though it does afford more room for the dizzy. The AC unit I installed included a heater core in the evaporator housing under and behind the dash. A bit tight and fiddly on the installation due to all the hoses, but worked out very well. You can see the "manifold" for the heat and AC hoses upper left in this picture:
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Now I see the heater control valve. Shoulda noticed it in the photos in the link. DUH!
 
SWC said:
Thankyou Mickey that's a great idea and will pass on.
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You're welcome, and I'm happy to share any info if he has any questions.
 
DrEntropy said:
Now I see the heater control valve. Shoulda noticed it in the photos in the link. DUH!
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At our age we do have a bit of slippage, don't we? :smirk:
 
If you want you can make a GM V6 look quite at home in an MG. This is the 3.4 in my rebodied MGA.

enginebayj.jpg
 
That is a fine looking install.

Grats
 
Mickey Richaud said:
The 60-degree GM V6 and T5 transmission combo is a great choice. Gobs more power than the B engine, about the same weight, and an easy conversion with lots of support. Here's the one I did a while back: > Mickey Richaud's 1969 MGB GT with General Motors 3.4L V6 <

Sold it a while back to downsize a bit, but sure do miss it!

Mickey
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Good day Mickey. Are there good instructions on how to do this conversion that you used? Everything that I have found has been lacking. I currently have a GM 2.8L V6 (out of a S-10) and am trying to find a "good" T5 transmission.
 
I wouldn't waste time on the 2.8 - less power and depending on what year it is a potentially weak bottom end. The 3.1 and partica placement is much more flexible engine.

Go to https://bmcautos.com/
 
onebrownshoe said:
Good day Mickey. Are there good instructions on how to do this conversion that you used? Everything that I have found has been lacking. I currently have a GM 2.8L V6 (out of a S-10) and am trying to find a "good" T5 transmission.
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Mornin'!

I bought all my conversion bits from Bill Guzman, company is Classic Conversions Engineering. I believe he has assigned some/all sales over to Brian McCullough at BMC Classic Restoration and Conversions in Minnesota. Bill had a very comprehensive set of instructions and was a big help. Brian has had vast experience with the GM V6 conversions. You might want to reach out to him.

Bill Spohn, posts above and he linked Brian's website, has also had a good deal of experience, especially with the 3.4 (same engine I had, though I chose the Holley 4 barrel over the fuel injection).

Finally, yes, the 2.8 will outperform the stock MGB engine. But it's one of those deals where, if you're going to make the switch, you'll be much happier with the 3.4, and there's a fair amount of them still out there, with plenty of parts and tech support available.
 
You will be putting a fair bit of money into the car and will possibly own it a long time A thousand or two saved now is pretty small compared to the end result you'd get by carefully choosing what parts to use. The absolute worst reason to justify use of a particular engine is that you already happen to have one. If you want a better result, sell what you have to someone else and source the best parts to get a premium result.

If you do decide to keep what you have, you better determine whether it is an early 2.8 with the weak crank, or a later one which isn't as bad.
 
The broblem with an MX5 engine is, you would need to modify the chassis rails to get it in, I have a freind that has just bought the engine and 6 speed box to do exactly this,
There is a company here in the UK that are bulding MGB's with the later MX5 engine which is a ford engine. these fit a bit easier.
 
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