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Discussion Starter #1 (Edited)
OK, first post, be kind.

I'm considering using a 06 IRS cradle as a basis for a non competition no rules track day non CTS car.
I expect:
1. to fabricate my own LCA, and convert to C/O dbl adjustables, heim joint style adjustable inners
2. Fab my own straight swaybar
3. Change out rear bearing hubs to vette track series w/ 5x 4.75
4. Change over to 14.4" CTS V discs
5. Calipers, not sure if OEM or Wilwoods yet
6. I want to keep the E brakes
7. I will add cooling ducts
8. I picked up a set of BMR trailing HD? arms, but I can't figure why the mid span vertical bend is absolutely necessary
9. I will likely cut off/remove lower OEM alum shock mounts off the uprights
10. I will use poly anywhere possible, as long as suspension does not bind
11. rims will be 20x11 range custom
12. And the coup de gras, I will rebuild as needed to install a Quick Change IRS rear with 930 CV's, the OEM rear is a goner, a Ford 9" is not an option

So my questions are:
a. Am I in the right place for these questions
b. is this suspension up to the task of 1000hp? Road race only, with 335's?
c. are later CTSV IRS parts interchangeable and/or more robust?
d. Anybody gone this path and have any results to share, I am not interested in reinventing the wheel
e, Since most wheel hop seems to be suspension compliance related, is it worth using a straight lower trailing arm if I have the needed clearances?
f. I am concerned about using so much poly, that with all the suspension arcs built in, some will start to conflict and bind, anyone seen this?

I finished the cradle work jig today, so I am chomping at the bit.

Any thoughts, and If constructive, I'm ears
 

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Well, alright then!

I'd be in for more details on the build for sure, you know, the one making 1000hp for road racing...that sounds like a good time!

I dont know that we have a resident suspension design expert, though we do have some rather experienced road racers and the like.
 

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Discussion Starter #3
Well, alright then!

I'd be in for more details on the build for sure, you know, the one making 1000hp for road racing...that sounds like a good time!

I don't know that we have a resident suspension design expert, though we do have some rather experienced road racers and the like.
Thanks, I intend to share what I learn on this project here.

On "suspension experts", I'm hesitant, they may rain on my parade., but if truth hurts, so be it

If filtered well on my behalf, I'm sure the info I need is out there.

We'll see.
 

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Youre gonna get rained on around here...if a raining is due...

Best of luck...and wtf is this ride its going in? So secretive.
 

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Discussion Starter #5
Youre gonna get rained on around here...if a raining is due...

Best of luck...and wtf is this ride its going in? So secretive.
Sorry as new member, don't want to throw any shade on the CTS crowd.

1972 Barracude w/440" SB Alum A8 w8 EFI centrifugal SC to get to 1K

Stumbled on this FWIW:

Old 10-27-2016, 08:29 PM #102
FuzzyLog1c
TECH Junkie
Join Date: Mar 2011
Location: Connecticut
Quote:
Originally Posted by hefftone View Post
If the suspension layout of the 2nd gen helps with traction..... then cradle swap with 8.8 would be where it's at. Cmon Creative Steel !
The V2 subframe geometry is identical to the V1 and so is the geometry of the control arms, tie rods, and trailing arms. I have a half dozen V1 and V2 rear control arms and spindles and they're virtually indistinguishable. The trailing arms are rotated 90 degrees for easier access to the bolts. Not a big deal unless you want to migrate your old trailing arms.

The only interesting differences between the V1 and V2 subframes are the dual front differential mounts and the metal shaping/welding process improvements. The quality is a little better and it looks a little cleaner due to the reduction in the number of welds.
 

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I don't see how 1000HP on 335s is a good idea regardless of how good the suspension and diff are. On my V, the car is loose at high throttle with 305s in the back. You're talking about ~2x the HP with a 10% increase in the amount of rubber to get that power to the road. I'm sure you intend to be lighter than the Cadillac but even so, this seems like a sub-optimal combination. My 02Z06 made 600HP and I also ran 305s and aggressive throttle was downright dangerous in the turns, the rear end would come loose in a heartbeat.
 

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The V1 differential will not hold power if you plan on using it. The V2 diff would be a much more durable choice unless you are just using the subframe as a base to fab in your Ford 8.8?

Post up some pics of this monster you're creating!

Sent from my SM-G965U using Tapatalk
 

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Discussion Starter #8 (Edited)
I don't see how 1000HP on 335s is a good idea regardless of how good the suspension and diff are. On my V, the car is loose at high throttle with 305s in the back. You're talking about ~2x the HP with a 10% increase in the amount of rubber to get that power to the road. I'm sure you intend to be lighter than the Cadillac but even so, this seems like a sub-optimal combination. My 02Z06 made 600HP and I also ran 305s and aggressive throttle was downright dangerous in the turns, the rear end would come loose in a heartbeat.
I agree, the 1000hp target is probably more for bragging rights. One of the reasons I leaned towards a centrifugal, as anything in the lower rpms is not going to the ground. However I am not shy about Aero/Wing usage, but will find my limit in trying to get enough front DF to make the rear wing a useful balance.. I play a lot with CF, so low weight is essentially free hp.
I weighed the OEM cradle complete last night, without wheels/rims, not sure what the fluid level was, approx 352lbs, which is heavier then I expected. OEM Rotors 1" 5x114 included in above weigh 15.4 lbs, they will be up sized. I expect when complete with my changes, I'll be adding somewhere 65-75 lbs, which IMO ,will be easier to accept because its all(?) below COG and near/over rear axle.
 

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Discussion Starter #9
So I decided on X tracker SKF-BR930555 bearing hubs, no tone ring, 5 x 4.75", 14mm studs, 33 spline, .54" flange, first brand new one to arrive feels like gravel replaced the grease.

Not sure how this could get by quality control. I'm not impressed.

Its being returned.
 

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Discussion Starter #10
Winters IRS Quick Change Showed up, Sweet. 930 CV, Gear Diff 1350, internal oil pump, now I get make it fit.:eek:
 
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