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wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 4:08 p.m.

So, I have been driving my swapped 3.9 rx8 for a few months.  Even competed in the challenge this year!  However, the steering geometry is fubar due to moving the rack down.

 

I have a new subframe and I'm trying to make it work without cutting it up.  My current issue is still steering rack clearance.  I can move the engine up and get rid of the issue, but then the hood doesn't close.  

 

It's close.  Like I can close the hood (after cutting substructure), but then I have like 3/16" between crank pulley and steering rack.  This is with the subfrme spaced down from the car about.....  3/16".

 

Goals:  

1) Stock rx8 brilliant steering.

2) no holes in the hood (unless for a spooli boi)

 

I don't mind fabrication.

 

So...

 

Stampie, dusterbd, angry, Travis, Robbie, Dan, whoever else is swap - compromise savvy....  got time for a 1 hour video chat this week?

.

Dusterbd13-michael
Dusterbd13-michael MegaDork
7/26/23 4:13 p.m.

I can make time one night not Thursday 8-9

Start by posting a metric berkeleyload of intake pictures with a hoodline reference from all angles. Im wondering if a little aluminum origami may help.

As well as rack/damper/other tight spot pictures. With pointers to interference and tight spots. It'll let my brain chew riding down the highway. 

 

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 4:20 p.m.

Okay, I can take pictures of crank to rack.  Then, I can take pics of alternator to hood.

 

The easy solution is cut hole in hood for alternator to stick out.  Don't want to.

 

The options are....  

1) move rack down.  I have a bunpsteer kit (in budget).  Can do this.  However, my initial attempt was too low and I couldn't solve the bumpsteer.  Would need to go "not as low".  Would require fabricating very specific and precise shims (available for $200....   not in budget).

2) move subframe down.  This is easy.  2 plates with 2 holes.  Raises ride height.  Not a huge deal.  Might be the way to go?

3)???

4) profit

5) something else that yall come up with!

Stampie
Stampie GRM+ Memberand MegaDork
7/26/23 4:25 p.m.

I'm down for whenever.

nocones
nocones GRM+ Memberand PowerDork
7/26/23 4:28 p.m.

Can you move the rack forward or backwards?   Yes this will slightly mess up Ackerman..  but will fix bump steer.   I could see if I could join a call.  But will second tons of pictures helping.

Dusterbd13-michael
Dusterbd13-michael MegaDork
7/26/23 4:30 p.m.

Alternator is the issue, not the intake?

 

Oh, we got this!!!

 

Get me pics. 

GameboyRMH
GameboyRMH GRM+ Memberand MegaDork
7/26/23 4:35 p.m.
nocones said:

Can you move the rack forward or backwards?   Yes this will slightly mess up Ackerman..  but will fix bump steer.   I could see if I could join a call.  But will second tons of pictures helping.

I was also thinking about a drift-style offset rack arrangement.

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 4:37 p.m.
nocones said:

Can you move the rack forward or backwards?   Yes this will slightly mess up Ackerman..  but will fix bump steer.   I could see if I could join a call.  But will second tons of pictures helping.

Front or back would be ideal.  It's how to do so.  I just need about 1/2".

 

However, the rck mounts are angled, so it goes up AND forward and since it's a circle (rack), the interference stays the same.  Pics incoming later.

kevlarcorolla
kevlarcorolla Dork
7/26/23 5:02 p.m.

Move the outer tie rods down with good heims and spacers.

 Much easier then moving hard parts ;)

RacetruckRon
RacetruckRon GRM+ Memberand Dork
7/26/23 6:05 p.m.

A picture dump would be helpful to get the brainstorming rolling prior to a video call. I'm in to help in anyway I can. 

AngryCorvair (Forum Supporter)
AngryCorvair (Forum Supporter) GRM+ Memberand MegaDork
7/26/23 6:13 p.m.

I'm honored by the invite.

i can't do thursday, but i can do friday or weekend.

and yeah, pix.

 

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 6:19 p.m.
kevlarcorolla said:

Move the outer tie rods down with good heims and spacers.

 Much easier then moving hard parts ;)

Down as far as possible.  Actually so far down that the tie rods rub the inner parts of the wheels at slightly less than full lock...  still has bump steer with the old subframe.  Hence the need for the new subframe.  

 

Rack doesn't fit in stock location without the crank pulley sitting on it.

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 6:21 p.m.

Friday at 8pm eastern?  If yall are available, send me an email at rabenr 45 @ g mail.com. (no spaces).

 

Pics will happen tonight or tomorrow

 

kevlarcorolla
kevlarcorolla Dork
7/26/23 6:46 p.m.

In reply to wvumtnbkr :

Bugger,good luck to you then :)

kevlarcorolla
kevlarcorolla Dork
7/26/23 6:58 p.m.

Space to relocate the inner control arm pivot up by modding the subframe?

 

 

 

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 7:12 p.m.
kevlarcorolla said:

Space to relocate the inner control arm pivot up by modding the subframe?

 

 

 

Do you mean down (if moving rack down)?  If so, that's an interesting thought!

kevlarcorolla
kevlarcorolla Dork
7/26/23 8:06 p.m.

In reply to wvumtnbkr :

 With my AE86 race car I modded the subframe to move the inner control arm pivot up to move roll centers back to something reasonable after lowering.

 Then moved the outer tie rod down the same amount to correct bumpsteer.

 Worked just fine.

Stampie
Stampie GRM+ Memberand MegaDork
7/26/23 8:20 p.m.

Just as a pre meeting prep isn't there a kit for the E36 rack into the subframe?  Does that help any?  I know the RX8 has electric steering.  Would the NC Miata rack be smaller and convert to power steering?  For some reason I have a RX8 subframe with rack installed sitting here.  Would it help to have pictures of that beforehand?

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 8:40 p.m.

Running a hydraulic rack would solve the problem but then create nother problem of needing a hydraulic pump.

 

Or depower a rack and install eps on the column.

 

Any of those solutions will leave me with a power steering warning light (not the end of the world).

 

They also require me to buy a rack AND a pump or motor.

Stampie
Stampie GRM+ Memberand MegaDork
7/26/23 8:47 p.m.

In reply to wvumtnbkr :

Are you still powered right now?  A pic of the point of cospacialness (™ Pete) would help.

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 9:19 p.m.

Yes, it is powered now.  It is n electric rack.

 

You got me thinking about the crank pulley.  I wonder if there is a smaller crank pulley that I could use.

Slippery
Slippery GRM+ Memberand PowerDork
7/26/23 9:31 p.m.

PM me if you need anything CNC machined. 

Stampie
Stampie GRM+ Memberand MegaDork
7/26/23 9:48 p.m.

In reply to wvumtnbkr :

I so want to make a joke about you thinking.

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/26/23 11:53 p.m.

I believe I have a 3400 pulley in the garage. Depending on what source I read, it might fit on the 3900 and be almost 1/2 inch smaller in diameter.  That 1/4 inch would be helpful!

wvumtnbkr
wvumtnbkr GRM+ Memberand PowerDork
7/27/23 8:27 a.m.

Okay, here are some pictures..

 

Rack to pulley clearance (I realize the pics aren't great) about 1/8 to 3/16" gap.

Subframe to chassis (still a 3/16" gap).

Alternator is touching the underside of the hood (still, barely)

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