Ultimate IRS Supra Coilovers – Suspension System for MKIV / SC300 Grannas Racing

The Grannas Ultimate IRS coilover suspension setup includes double adjustable shocks, along with adjustable lower rear control arms. This allows you to not only fine tune the shocks, but also adjust your camber for maximum contact patch when the car is squatting on launches. The setup does not use a bolt-in body shock but rather a more mainstream and readily available dual eyelet shock for easy servicing and replacement in the case of a failure at the track.

These will bolt into your stock supra. The Ultimate subframe is NOT required to run this setup! 

The kit is both front AND rear shocks. The mounts include mounting provisions for travel sensors so you can fine tune your suspension on launches, going around/down the track, as well as on hard cornering for the road course guys!

This full 4130 chromoly construction control arm and upper hat mount setup allows for use of a double adjustable shock, which allows you to not only set compression, but also rebound, which is really important in setting up an IRS suspension. Rebound allows you to control how quickly the car comes back up from the squatting position, this allows you to keep the car planted rather than bouncing up and down when the car unloads, such as in a 6-speed car during shifts!

Not only does the GR Ultimate control arm setup allow for the use of a common affordable shock options, but it also allows for camber adjustment with the lower control arms single adjustability.

This kit includes upper hats that bolts into the factory shock tower locations an adjustable lower control arm, and front mounting brackets. The front suspension system uses the factory control arms. It bolts into the factory mounting points and used the factory spindle. No modifications are required to run this suspension. Factory sway bars can be used. 

There are three coilover options currently. The base kit uses Strange brand double adjustables. The middle tier kit uses double adjustable Penske based coilovers setup specific for the Supra by Precision Racing Suspension. The top of the line coilover is again a Penske based strut but with an additional canister which allows for finer tuning of the suspension. 

Current Shock Options:

• Strange double adjustable coilovers with 350 lb springs rear / 550 lb springs front
• “PRS” Penske based strut which are custom valved for the Supra chassis and they are double adjustable (no canister) w/ 350 lb strange springs 
  rear / 550 lb springs front
• “PRS” Penske based strut which are custom valved for the Supra chassis and they are double adjustable with fine tuning canister adjustment (same setup I run on my 6-speed car) w/ 350 lb strange springs 
  rear / 550 lb springs front

A lot of people ask how would these compare to HKS Drag coilovers… well, the difference is night and day. You are talking about 20 year old technology based on a factory mounted strut compared to current racing technology. All of the coilovers I offer are double adjustable. HKS Drags are only single adjustable. The double adjustability (rebound control) allows you to control the speed at which the shock “rebounds” from a squat. That is key when it comes to IRS and keeping the car planted going down the track. This is especially helpful in a manual transmission car, where the car will unload and come out of squat on every shift. The double adjustability allows you to tune the suspension to keep the car planted on shifts.