Sub-frame jig

[clairetoo]

I have been a bit busy helping a friend fit a KLDE V6 (Mx6 , Ford Probe etc) into an Mx5 - the engine went in recently , but there are a few clearance issues with the sump and exhausts .
It turns out thee is a tubular subframe available in the states which would solve all the problems , but at $1095 (plus shipping and tax's) it is just too pricey - I took one look at a picture of it , and foolishly blurted out "looks dead easy to make , I could do that"............
So here I am , a week and a bit later with a finished jig sat on the bench and a bit of workshop time coming up over Christmas
The original subframe has now been removed from the jig , but I am taking a couple of days off to work out the fine details before I start (oh , and to get Christmas over with as well !)

 

[chap]

So if you know the engine fits, can you locate it using the existing subframe and bolt it to the jig? Then you can form the new subframe round it?

 

[clairetoo]

The plan is make the new subframe without engine mounts , then make new mounts to suit with the engine in place as the current ones have been made to fit the stock Mx5 position on the `frame .
And then add the stock mount positions to the jig later so it can be produced to fit any stock Mx5 .

 

[chap]

I meant initially bolt the engine to the jig (seeing as you know where it needs to sit in relation to the existing subframe) then remove the old suframe and build the newone.
This way you can make sure all the critical areas clear.
Is the idea for the frame to fit the stock engine as well as the new engine then?

 

[clairetoo]

Ah - just re-read you first post
We have done some measuring under the car (the engine is already in , just needs a sump and exhausts to complete the conversion) , the jig is so I can get all the wishbone/steering rack and body mounting points in the right places .
Everywhere something needs to go , there is subframe in the way - the replacement will solve this .
This is the one from Flying Miata - mine will be very similar

 

[chap]

Ah - just re-read you first post
We have done some measuring under the car (the engine is already in , just needs a sump and exhausts to complete the conversion) , the jig is so I can get all the wishbone/steering rack and body mounting points in the right places .
Everywhere something needs to go , there is subframe in the way - the replacement will solve this .
This is the one from Flying Miata - mine will be very similar

The best way to do it IMO.
I thought seeing as you must have already made up engine mounts, you may as well use these to get the engine located within the jig, make mounts to hold to jig, then remove the engine to frame mounts and build new frame.
It does look like it's quite a simple frame though (the one you're basing your design on), so maybe this is getting too envolved!

 

[the snooper]

foolishly blurted out "looks dead easy to make , I could do that"............

hmm i used to do silly things like that and before you know youre more involved then the guy that started it.
bite your tongue it helps no end

 

[clairetoo]

hmm i used to do silly things like that and before you know youre more involved then the guy that started it.
bite your tongue it helps no end

It would seem that I hear myself say `I could do that' , but what is heard by other's is `I would love to make that for you...'
I started by making the parts to join the engine (Ford Probe KLDE V6) to a Mazda Mx5 gearbox for a friend - I have since made a set of throttle bodies for it , and then helped pull the original subframe off to make the jig !
A bit of progress has been made over the last few days - but damn! it's been cold in the garage

 

[chap]

Looking good there!

 

[clairetoo]

Well , since the `big freeze' seems to over at last , I finally got back into the garage and finished the subframe off
I was held up a bit by running out of 2mm steel sheet for the top mounts , and a bit of uncertainty over how to do the rear mounts - the American one uses two tabs each side which I thought looked a little flimsy - but this morning I had an idea , so just got stuck in !

rear mounts boxed in 5mm sheet

And finally off the jig

 

[lchris21]

awesome stuff

how did you bend the tube ?

 

[clairetoo]

Thanks
I used a record plumbers pipe bender (with a bit of an extension on the handle and the back feet hooked into my engine stand !)

 

[Bigjoe]

"I could do that".......not just me that says things like that then!

Looking good Claire, makes you feel good saving a fortune does'nt it

 

[clairetoo]

"I could do that".......not just me that says things like that then!

Looking good Claire, makes you feel good saving a fortune does'nt it

Strange thing is............when I say "I could do that" what people seem to hear is "I would love to make that for you" ...............

 

[Bigjoe]

Thats why i keep my mouth shut these days!

have you got any pics of your kitcar?

 

[rikrobson]

You gonna get it powder coated then?

 

[clairetoo]

You gonna get it powder coated then?

No time for that
So tonight it got a good coat of zinc-rich primer , then a generous top coat of black synthetic - looking pretty good

 

[Angusdog]

Very nice quality job. Did the tube flatten much when you bent it? There's loads of stuff on the net for tube benders, as that's the one area where it all gets a bit complicated. I would like in the future to construct one and then think of an application