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Posted by: cwpeden Jan 24 2016, 05:40 PM

In my vanilla 73 2.0 I'm at the top of the autocross field in my area, Porsche wise.
Now I need to beat the Miata's.

I'm going to start with a EJ251 I just picked up.

Asking everyone who has done or help with a conversion. What would you do differently with respect to supporting the engine and trans?

Is a full cradle required or is supporting from the front and rear preferred?

What wasn't strong enough?

What has or hasn't failed?

Too stiff?

Too flexible?

What was in the way?

I'm going to use stock rear points what about the front?

Thanks for any suggestions.

Posted by: r_towle Jan 24 2016, 05:48 PM

You cannot support it from the front, the engine mounts are in the middle of the engine.

Look for a few cradle designs, but basically it is two tubes running from the rear tranny mounts up to the engine cross bar. Off those two bars are short legs to motor mounts on the engine.

Rich

Posted by: veekry9 Jan 24 2016, 05:56 PM

Something wrong with your 914?
Miatas should be easy on the short track.
The never ending search for more power,the chilled turbo beckons you,whispering 'power to weight and cruise economy'.


The front mount attaches are still the way to go,a beam is needed to pickup the soobee mounts and rubber bushes,a trapezoid set of tubes or fabbed I beams from plate.
A few here have made the install without issue.On your back under the car looking up,tapemeasure the distances and draw it out to scale.I presume you have a welder at hand.I read somewhere there is a fellow selling kits,Renegade,I think.

yeah,here it is
http://www.renegadehybrids.com/

Posted by: cwpeden Jan 24 2016, 06:17 PM

That's what meant. But I thought I saw a front mount, maybe the one that stops engine 'rotation'?

Posted by: cwpeden Jan 24 2016, 06:18 PM

The local Miata's are either turbo's or supercharged...

Posted by: r_towle Jan 24 2016, 06:20 PM

The two side bars go to a cross member that uses the original 914 bar mounts....

Posted by: tazz9924 Jan 24 2016, 06:37 PM

Yes u can small car makes mounts that allows you to mount it to the stock bar.

Posted by: effutuo101 Jan 24 2016, 06:52 PM

Not sure if Ian is make these any more. Also Renegade Hybrid has a great one.



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Posted by: Mike Bellis Jan 24 2016, 07:51 PM

Mine was built to fit any motor. The bolt on engine mounts fit my Audi 1.8t

Posted by: DBCooper Jan 24 2016, 08:13 PM

This the Smallcar mount, to put a Subaru engine into a vanagon:



It’s three piece and for a 914 you only use the two side pieces that bolt to either side of the engine. That front cross piece with the VW transmission cradle is discarded (or if you’re nice Smallcar will sell you just the side pieces) and that’s where it attaches to the stock 914 front engine cross bar. If you’re using the 901 transmission you can use the stock 914 transmission mounts, if you’re using a Subaru transmission then you’ll need to make your own. IMPORTANT: Stock Subaru turbo engines’ exhaust crosses from one side of the engine across the front to the other side, but this SmallCar mount is in the way. That means to use this mount with a turbo engine you’ll need to redesign the exhaust/turbo location and re-plumb everything. That's when a cradle makes a lot of sense.

This is a typical cradle, home made:



The front mounts where the stock 914 engine bar mounts, the rear where the stock 914 transmission mounts. You can see the cross bar with the stock Subaru motor mounts in place. Pretty simple, it's really just a sub-frame, and it’s open, making it easy to plumb the exhaust, etc.

Posted by: mgp4591 Jan 24 2016, 08:17 PM

Mike, I know your tube cradle is made from fairly lightweight stuff and is easily strong enough but do you have a total weight for that assembly?

Posted by: Mike Bellis Jan 24 2016, 08:21 PM

27 LBS

Posted by: veekry9 Jan 24 2016, 08:23 PM

Hey,thassa belisimo.You obviously comprehend 'triangulation',Seamless tube?

Posted by: Mike Bellis Jan 24 2016, 08:26 PM

It's built with DOM .120 wall seamless tubing; 3/4", 5/8" & 1/2".

Posted by: 76-914 Jan 24 2016, 09:06 PM

Here's mine. A variant of DB cooper's that doubles as it's dolly. Mine is 4130 .090" Chromoly.

Posted by: aircooledtechguy Jan 24 2016, 09:28 PM

That is one slick unit you made. Nice job!!

Posted by: cwpeden Jan 25 2016, 02:41 PM

What is the prefered arrangment with regards to mounts.

Hard mount cradle to car and soft mount engine/trans or other way around?

Posted by: Mike Bellis Jan 25 2016, 10:34 PM

That is a matter of choice. Hard mount will transfer engine noise. Soft mounts break (in my case). On my first V8 conversion, Ford 5.0 EFI, I had it idling and slowly let out the clutch. BAM! broke 2 new 911 transmission mounts. I switched to solid mounts. That was 24 years ago...

Posted by: DBCooper Jan 25 2016, 10:58 PM

I love that engine.