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100-4 Engine Options

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boxofparts

boxofparts

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I am trying to help a friend who has a 100-4 that has a GM V6 engine conversion. He wants to put it back to something original.

Best option would be to find an 100-4 engine, or something out of an A90?

What engine swaps would be the most acceptable? A Miata sounds easy, but the 2.0L might not provide the torque of the original.

I am not sure how chopped up the firewall and inner fenders are with the current GM engine.
 
"back to something original" would be a 100 engine. A90 engines are likely harder to find. An Austin taxi engine would likely be easier to find, but it would be diesel.
 
Dougie - it has already been done on a Healey BN1 - F20C with six speed stick. 240 hp and 9000 rpm red line - my favorite engine swap….


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boxofparts said:
I am trying to help a friend who has a 100-4 that has a GM V6 engine conversion. He wants to put it back to something original.

Best option would be to find an 100-4 engine, or something out of an A90?

What engine swaps would be the most acceptable? A Miata sounds easy, but the 2.0L might not provide the torque of the original.

I am not sure how chopped up the firewall and inner fenders are with the current GM engine.
Click to expand...
Hi -

I have an 100 motor and head.

The motor is actually for an A90 so the differences are:
1) distributor clamp mount only has one bolt hole, not two and
2) the head has short rocker studs but these can be replaced with new ones.

You'd have to arrange for someone to pick up the motor (I don't want to pack it) it is located in Northern California. Given the troubles I'm happy to let it go for any reasonable offer.

please DM me if you are interested.

Cheers
 
Guido36 said:
Dougie - it has already been done on a Healey BN1 - F20C with six speed stick. 240 hp and 9000 rpm red line - my favorite engine swap….


View attachment 80534
Click to expand...

Nice!
Very clean engine bay as well which is aways a plus.
 
This just came in from a email list I'm on. If interested, let me know and I'll put you in contact with the seller. He's in Vallejo, CA, a long way from you, but worth a shot.

"I have a 100 motor and head available in Northern California. I don't have the manifolds or rocker but the engine has the crank in it.

Willing to part with it to anyone that can pick it up this coming week + offer.

The motor is actually for an A90 so the differences are:
1) distributor clamp mount only has one bolt hole, not two and
2) the head has short rocker studs but these can be replaced with new ones.

Other than that the motor is identical. I will visibly inspect it tomorrow so can provide pics if anyone is interested."
 
Hopefully the guy is watching this forum.. I have a feeling that he is in the early stages of creating a barn find vehicle. Vehicle does not run, parked in garage, wife is oblivious to his project, too busy in life to deal with it and nobody to help work on it. I did not offer to help as the car is 300 mile south of me in SE Michigan. So in summary... there is a barn find 100-4 collecting dust as we speak.

I am surprised nobody brought up doing a 2.3L Ford.. There were plenty of Thurnderbird Turbo Coupes. The Pinto 2.3L NA engine was also races with pretty good results and lots of parts out there too. Ranger 2.3L Twin Plug too... Nice thing about these you could get a nice transmission in the package. Plenty of intake and exhaust options to even take it back to SU carbs Mega Squirt and EFI would also be an option.
 
All - I have broken down the motor and the short block & crank are now sitting in a skip to be sent to the dump.

If you want the motor you need to tell me now.

The motor is rusty but rebuildable.
 
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