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My partner and I have a VW powered Bonneville Lakester that we need help designing a Rear IRS suspension with most components inside of the bodywork to reduce drag. I thought that the Super Vees used IRS and would be a good place to start. I can't seem to find any diagrams with the shocks inboard over the trans. Our Lakester will be mid engine. We have 3 engines to use from a 252 hp 2332cc to a blown 36 hp and Darrell Vittone has offered the use of his NA 36 hp engine which made 150 hp. Any help or knowledge would be greatly appreciated.

Super vees had real suspension, double a-arm, coil over. I think swingaxle would be the best for having the minimum aero cross section.
I mean Formula v swingaxle, with a radius rod, and inboard coilovers

Competitive formula-Vees have all gone to 0-roll suspension set-ups. Single shock! This seems ideal for an LSR car since it sets up the swingaxle to act like a solid axle - keeping both tires flat on the tarmac - or salt as the case may be.

Here's one version:

I looked at Zero roll and it may work with a bit of modification since rules state 1 shock pre suspended wheel.

Note that "0 roll" is abbreviated from 0 roll resistance. The purpose is to avoid oversteer by giving more traction to the rear axle.
To give 1 shock per axle, you just use 2 parallel shocks instead of 1. It would keep things out of the airflow pretty well.

I'm going to use your suggestions and talk to the Hewland builder and see if we can still build a 6 speed as a Swing insyead of IRS. I'll lose the inboard disc brakes but gain in simplicity.

Well, you can also build an actual solid axle. I have no experience, but I've seen drag racers with one.
I don't know why you would need a 6 speed if you have a push truck get you up to ........... speed.
You're not doing 130/150 club with this are you?

6 speed for multiple engines, yes running in multiple classes including 150 club. I already have a solid axel set up but the inspector questioned the load bearing capacity of the bearings. No push trucks allowed at the Mojave Magnum, Denver Mile, or anywhere except Bonneville or El Mirage. I'm not putting my hopes to run in just 1 basket.

Dual shocks in parallel may be bit of a stretch of the rules, but it would be one shock per wheel .... Think one really weak shock with almost no working value (sort of along just for the ride), and one that is adjustable to fit any condition... Simplifies suspension adjustments... Might want to pass this by tech before actual car mods though....

Dale

Was told last night that SCTA has outlawed swing axles in the Lakester class. I have to verify this now.

Any update inquiring minds want to know...

Dale

Yes, I talked to 3 SCTA inspectors and all 3 said that VW transaxle is totally fine, they are just concerned about retaining the wheel if an axle breaks. I believe the problem came up as the SCCA had outlawed the Swing or so I was told. We haven't decided yet but we are leaning towatd using disc brakes to overcome the wheel retention.