´Dog bone´ subframe spacer

[Petrus]

Does anyone have accurate measurements of the TRD Sportivo ´dog bone´ or the crucial dimensions; distance bore centers and bore diameter.

Perhaps anyone with a subframe lying about can make the measurement?
Mind; it needs to be accurate as there may be a reproduction in a properly suitable aluminium alloy forthcoming.

Thanks!!

[Carolyn]

Does anyone have accurate measurements of the TRD Sportivo ´dog bone´ or the crucial dimensions; distance bore centers and bore diameter.

Perhaps anyone with a subframe lying about can make the measurement?
Mind; it needs to be accurate as there may be a reproduction in a properly suitable aluminium alloy forthcoming.

Thanks!!

The hole is clearance for M12.  Why not measure the centres on the bolt-heads on your car?

[Petrus]

Will do when I can get properly under it.

It will be anodised 7075 alloy by Boris.

[Petrus]

Btw. good question from Boris: How many of you would be interested in a set?

If I am the only one, it would be silly to fabricate them from 7075 and anodise a batch.

I will have to have the local metal worker cut a set from pisspot steel then 

[jvanzyl]

Btw. good question from Boris: How many of you would be interested in a set?

If I am the only one, it would be silly to fabricate them from 7075 and anodise a batch.

I will have to have the local metal worker cut a set from pisspot steel then 

Question becomes how much?

Ask him for pricing if he gets 10 - 20 - 30 people... but I think people would need to hear some first hand experience (possibly from yourself) on what the difference actually is...

[Petrus]

Chicken and egg Jan.

For experiences Spyderchat is the source as the kit has been mounted there by several members.

For mé, personally, TRD adding it to the kit is reason enough to go for a set. Whether from the local metal bender or even from high tech Boris, the price is not going to break the bank. The latter is véry reasonable with his belly brace too imo.

[Dudi]

What's the purpose of this part?

Change the position of the subframe to allow for shorter shocks thus maintaining driveshaft angles?

[Petrus]

What's the purpose of this part?

Change the position of the subframe to allow for shorter shocks thus maintaining driveshaft angles?

The lowering of the subframe lówers the bottom suspension arm mounting = goes the same way as lowering spring = lower the roll center.

[SuperArt]

For mé, personally, TRD adding it to the kit is reason enough to go for a set.

TRD don't always create items with real benefit to the car's dynamics. Case in point my rear strut tower brace does nothing except look pretty. Other owners of the TRD rear strut brace report the same. The front however is a different story, that has a night/day difference.
Would be good to have first hand reports on the difference these dog bone parts make, sure they're about somewhere on the inter webs.

[Petrus]

TRD don't always create items with real benefit to the car's dynamics.

While true; the form is partly no different from other ´go (no) faster´ sellers, in thís case it serves a function or they would not have bothered with an invisible spacer.

[Snelbaard]

Just to give this thread a bump, I'm still planning to make these dogbone replicas. However I still need to know the distance between the centres of the circled holes. Does anyone know this? I can't easily lift my car up to measure it myself, but maybe some of you can.



(photo credit 8thumpers)

[Mark A]

I can measure these for you tonight

[Mark A]

Do you have an email and I'll send you pictures confirming the measurements.

But they appear to be 15cm at its greatest diameter distance and 11.7cm at its narrowest point, hope that makes sense.

Mark

[Snelbaard]

Thank you so much Mark! That's fantastic. It does make sense, and I'll send you a pm with my email address.

again: thank you!

[Topdownman]

Am I right in thinking that there are pre and post facelift subframes? I seem to remember hearing this although not sure why this would be.

If so, may be worth trying to check those measurements are the same for both?

[Snelbaard]

Yes I thought about that and it will probably be worth checking. On the other hand I think it unlikely there would be differences in this respect. After all: Both types of subframe bolt onto the chassis in the same way. I doubt the chassis itself would have been changed in this respect. But you never know.

So Mark, is yours a pre-facelift or a facelift one?

[Nvy]

This sub frame dog spacer thing is useless w/o the other Mods that the TRD did. It fixes the geo of the axles and their angle to the tranny. I have no idea why one would want to have them with no other mods.

[thetyrant]

I wouldnt waste your time making them, if anything its going to have a negative effect on suspension geometry, what you actually need when lowering a car is to raise the subframe up to retain the suspension arm angles but of course car body is in the way for that, ive no idea what TRD were thinking with these spacers!

[Snelbaard]

Well, I now have the other mods. And there are quite a few people (especially in the US) who have been able to acquire the shocks and ARB's, but the subframe spacers are always missing.

@ thetyrant: Well I'm no vehicle dynamics engineer, but lowering the roll centre by lowering the lower suspension pickup points does make sense to me. But let's be clear here: The spacers are 3mm thick. I agree that unless you're pushing the car to the absolute limits of its abilities, you're probably not going to notice any difference.

[Mark A]

So Mark, is yours a pre-facelift or a facelift one?

The picture is of a preface subframe but it was replaced with postface lift subframe and matched up ok so I suspect no difference in the mounting holes.

Mark

[thetyrant]

@ thetyrant: Well I'm no vehicle dynamics engineer, but lowering the roll centre by lowering the lower suspension pickup points does make sense to me. But let's be clear here: The spacers are 3mm thick. I agree that unless you're pushing the car to the absolute limits of its abilities, you're probably not going to notice any difference.

Your right lowering the roll centre generally does make sense to improve geometry angles and help with bump steer etc by levelling out the suspension arms , however fitting these spacers doesnt do that from what im looking at and fitting them lowers the inner suspension pickup points by moving them away from the body,  but if on lowered springs which i believe the TRD are ?  then you have already raised the outer end of the same arm!, so coupled with the spacers the arm angle is steeper when your trying to keep them level ideally at static position.

Whiteline and a few others do roll centre correction kits for some cars and what they do is use a longer outer ball joint to correct the raised position of hub that lowering the car has given, these spacers do the opposite so not sure what they are intended to do, im sure there is a reason but its not to correct roll correction and i cant think why they would make them, if you jacked the car up higher then yes they would help but not when lowering it.

3mm isnt going to make much difference but its going to be a negative effect on geometry so why do it ?

[Snelbaard]

Yeah I guess you're right. Then maybe -but this is just conjecture- TRD figured that the lower roll centre as a result of the lower springs wasn't quite low enough, and needed further lowering by these spacers. Even if that means the lower control arms point up slightly. As such they wouldn't be roll centre correcting spacers, but rather roll centre lowering enhancing spacers. Who knows! What I do know is that there can even be a demand for useless things

[Petrus]

3mm isnt going to make much difference but its going to be a negative effect on geometry so why do it ?

Those 3 mm are a bit more in the roll center because that is a virtual ´point´ in the middle of the track. The ´point´ is determained by a line perpendicular to the rear shock strut and the angle of the lower supension arm.
In the TRD kit the ride height is lowered, which has three effects:
It lowers the cog.
Makes the angle of the strut greater.
I chnages the angle of the suspension arm.
The latter two move the roll centre down. It would need drawings to scale to knów, but I suspect that TRD sought to correct that a bit. Or perhaps to reduce the distance between cog and roll centre.
One thing seems obvious; that they would not have come up with an invisible mod. if it had no sense.

[Snelbaard]

Thanks to Mark A I've already been able to whip up a quick 3d model of the part. Just waiting on pictures to confirm the measurements and then I can have them cut!

[Mark A]

Did you not get the pictures?