got my tubular subframe - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Race Prep Miata race-only chat.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 02-27-2013, 05:40 PM   #21
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

Those pictures make me want to tear my still not back together car apart to cut more stuff off.
mcfandango is offline   Reply With Quote
Old 02-27-2013, 05:45 PM   #22
Elite Member
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,475
Total Cats: 114
Default

Quote:
Originally Posted by Leafy View Post
But you cant combine the rules. You either have to comply completely with the GT rules (minus any exceptions the solo book specifies) or you must completely comply with the solo rules.
Can't run a GT spec car in XP period but I donít see how that stops you from building a single car that can comply with both sets of rules at the same time.

Seems like the best way to do this however is might be to build a Simi tube chassis Miata for GT2 with a rotary. The 15X7 max wheel size for GT3 is killer but I suppose you could run different wheels for the different applications.
bbundy is offline   Reply With Quote
Old 03-01-2013, 12:48 PM   #23
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

So, given the desire to move the engine back: What is the easiest way to handle the PPF? The diff mount is relatively easy to work something different up. The transmission is a little harder. I'm not keen on doing the cross frame rail transmission bracing that the V8 conversion do.

This is on the list of stuff to do to the XP car... eventually.
mcfandango is offline   Reply With Quote
Old 03-01-2013, 12:56 PM   #24
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Are you allowed to modify the PPF in your class. Its kind of sketchy in my class, I define the PPF as a drivetrain mount so I can mod/remove/replace it but it might not be one to some people. If you can mod it, hack it off in the middle somewhere and weld it back together. You should then get it solution heat treated to get the strength back but that may or maynot actually be required.
Leafy is offline   Reply With Quote
Old 03-01-2013, 01:57 PM   #25
Elite Member
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,475
Total Cats: 114
Default

Quote:
Originally Posted by mcfandango View Post
So, given the desire to move the engine back: What is the easiest way to handle the PPF? The diff mount is relatively easy to work something different up. The transmission is a little harder. I'm not keen on doing the cross frame rail transmission bracing that the V8 conversion do.

This is on the list of stuff to do to the XP car... eventually.
Cut a little off each end and re-drill holes was my plan for PPF. That and make a shorter drive shaft.

XP allows swapping to completely different engines like a V8 or a rotary which requires changing drivetrain mounting entirely and figuring out how to position it so I can't see why shifting the stock block motor back as close to the firewall as you can get without having to modify it for any part of firewall for clearance to the block or head would be an issue.

I say that but every time I try and interpret SCCA rules I get confused or pissed off.
bbundy is offline   Reply With Quote
Old 03-01-2013, 03:17 PM   #26
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

In Prepared, the transmission is "open". If you swap out to say a T5 or T10 style unit. None of those have tail housings to connect to a PPF or torque tube. You would have to create a mount somehow. Abusing the PPF and chassis would be legal from what I read of the sections, 17.2.B/C/D.

XP is a slightly different beast.

I doubt you'll meet many DP (or FP) Miata that have abused the PPF to move the engine back. It is a lot of work. The Nationals winning DP (I know the owner) for the last 2 years is well enough weight balanced for pushing the engine back to not be necessary. Sure a 10/10ths build would require it. But with Solo, I think more seat time and tire testing will benefit over the slightly better weight balance.

I'll have to spend some time with the spare PPF I have. I dont know if you can get away with just redrilling the mount holes. IIRC, the PPF gets taller at the transmission and diff. I think the easiest way would be chopping a section out of the center and reinforcing to make it more like a tube than C-channel frame.
mcfandango is offline   Reply With Quote
Old 03-01-2013, 09:35 PM   #27
Junior Member
Thread Starter
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

Quote:
Originally Posted by mcfandango View Post
Those pictures make me want to tear my still not back together car apart to cut more stuff off.
Well if it's still not back together what is holding you back? Cutting stuff off is free and fun. Of course what you have to do BECAUSE you cut stuff off isn't always cheap or easy - but it's usually still fun!
guttedmiata is offline   Reply With Quote
Old 03-03-2013, 05:35 PM   #28
Junior Member
Thread Starter
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

12.8 pounds net savings.
Attached Thumbnails
got my tubular subframe-imag0178.jpg   got my tubular subframe-imag0179.jpg  
guttedmiata is offline   Reply With Quote
Old 03-03-2013, 06:10 PM   #29
Senior Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Sweden
Posts: 1,391
Total Cats: 58
Default

A light grey paint is useful for finding future cracks.

Looks good but getting the engine in would be a nightmare for me.
NiklasFalk is offline   Reply With Quote
Old 03-03-2013, 08:59 PM   #30
Elite Member
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,475
Total Cats: 114
Default

Quote:
Originally Posted by NiklasFalk View Post
A light grey paint is useful for finding future cracks.

Looks good but getting the engine in would be a nightmare for me.
I think the procedure for installing an engine would be
1) install engine in sub frame
2) lower car on lift down on sub frame
bbundy is offline   Reply With Quote
Old 03-03-2013, 10:30 PM   #31
Junior Member
Thread Starter
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

Quote:
Originally Posted by NiklasFalk View Post
A light grey paint is useful for finding future cracks.

Looks good but getting the engine in would be a nightmare for me.
I haven't read or heard anything about these subframes cracking. Do you know something I don't?
guttedmiata is offline   Reply With Quote
Old 03-04-2013, 03:01 AM   #32
Senior Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Sweden
Posts: 1,391
Total Cats: 58
Default

Quote:
Originally Posted by guttedmiata View Post
I haven't read or heard anything about these subframes cracking. Do you know something I don't?
I was just extrapolating the vibration from the engine transmitted through your new mount "towers".
It's not alu of course, but it never hurts to catch cracks early (e.g. check each time the engine is out).

But if it doesn't crack or break slightly, it's to heavy
NiklasFalk is offline   Reply With Quote
Old 03-04-2013, 09:52 AM   #33
Elite Member
iTrader: (2)
 
miata2fast's Avatar
 
Join Date: Aug 2009
Location: Dover, FL
Posts: 2,894
Total Cats: 109
Default

Quote:
Originally Posted by NiklasFalk View Post
A light grey paint is useful for finding future cracks.

Looks good but getting the engine in would be a nightmare for me.
I am looking forward to knowing if that is the case. I think it may have been better to have a wedge shaped spacer between his mount and the block. Or even just a flat spacer that is slid into place after the motor was lowered between the mounts.
miata2fast is offline   Reply With Quote
Old 03-04-2013, 10:12 AM   #34
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

Looks good. I agree it would be fun to get the engine in there but probably doable with some helping hands. I usually end up pulling/replacing my motor solo though.

As far as cutting more stuff off: The car HAS to be ready for the Texas Tour in a few weeks. Just fired up the new motor for the first time last night.
mcfandango is offline   Reply With Quote
Old 03-04-2013, 07:55 PM   #35
Junior Member
Thread Starter
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

Quote:
Originally Posted by miata2fast View Post
Or even just a flat spacer that is slid into place after the motor was lowered between the mounts.
There are aluminum spacers that go between the subframe and the block. They are bolted to the subframe in the second set of pictures.

I'm not too worried about getting the engine in. However, pulling the engine and tranny together won't be an option any longer without dropping the new subframe.
guttedmiata is offline   Reply With Quote
Old 06-26-2013, 11:43 PM   #36
Junior Member
Thread Starter
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

Quote:
Originally Posted by NiklasFalk View Post
A light grey paint is useful for finding future cracks.

Looks good but getting the engine in would be a nightmare for me.
Not bad at all. That is once the engine hoist was lowered back down and the tranny removed from the engine. didn't think that one through. Tranny had to go up from the bottom.
guttedmiata is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
1997 Miata Misty_Miata pineda92 Meet and Greet 4 09-20-2015 10:22 PM
Suspension difference(s) between NA and NB d k Race Prep 11 09-09-2015 06:12 PM
Dsm t25 big16g or somethig else? karcher DIY Turbo Discussion 0 09-06-2015 06:02 PM
1badmx5 for sale! 1BadMX5 Cars for sale/trade 35 05-18-2008 01:38 PM
Red Beast might be for sale... rmcelwee Cars for sale/trade 5 07-17-2006 04:38 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 07:20 AM.