Front swing arm bushes – what is the best practice and state of the art?

Mrtask, if you havent already, check out the early MX5 5 speed gear change - very short throws, very precise, not heavy or stiff. Have had 2 NA (89-98), and now a Lotus 7 clone Clubman with a 96 1.8, turbo, that puts out 215rwhp, spins to 7200rpm, has been tracked, and gearbox shows no sign of issues. Mind you it only weighs 750kg. I had one visitor who tried the box say he was amazed it was stock.
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Or you could go for the later landrover box that went into the MG RV8 LT230 I think.
Lower link bushes need to be soft material as the two elements fight one another when going up or down. Thats why you leave the bolts loose till the suspension is settled down then tighten them up; so you don't load the bush in the static position. the race cars had new one piece lower links made up to stop them tearing apart.
 
Given the time frame you mention Cobraboy, I imagine I don't have Alan's uprated bushes, so I'll have to get in touch with him.
JP928, that looks, well, frankly terrifying! You're a bit too far away for me to try your gearbox.
Mike Coombs, I think later MG V8s had a more advanced iteration of my gearbox labelled R380 or something, and I was given to understand they are rare, expensive, and allegedly not really much of an improvement over the LT77. All hearsay. I've never driven anything with either a Mazda or later Land Rover gearbox so I'm not speaking from experience. Thanks for the info about softer lower bushes and not tightening the bolts before the car is settled. I've got purple poly everywhere, and I don't recall precisely but I suspect the bolts were tightened long before the car was fitted with a drivetrain, interior, external panels etc. etc. !! Perhaps that is another reason for all the noises it makes when it actually propels itself along!? Lots of food for thought, anyway.
 
I used power flex purple bushes on a Saab 900 years ago. Ended up removing them as they felt too harsh with pot holes NJ roads, seemed to create more cabin noise without a huge improvement in handling. I don’t think I’d repeat their material. I have made my own bushes using industrial polyurethane resin that I post cured to get the best properties. They seemed to hold up well, I added an internal 3D printed structure to try and control bias and deformation. They were used on a Fulvia and we’ve not received any complaints yet.
 
The early mx5 5 speed box is fantastic I have to say. If you could get that feel behind the RV8 and it to handle the torque you’d have a winning combo for sure
 
Or you could go for the later landrover box that went into the MG RV8 LT230 I think.
Lower link bushes need to be soft material as the two elements fight one another when going up or down. Thats why you leave the bolts loose till the suspension is settled down then tighten them up; so you don't load the bush in the static position. the race cars had new one piece lower links made up to stop them tearing apart.
You are after the R380 box, the LT230 is the transfer box.
2 wheel drive R380s are scarce items as far as I have read, though.
 
I had an R380 in a Disco2 in Saudi behind a 3.9L, and found it to be fine. Rumour has it they are an upgrade to Lt77, with synchro on Reverse, requested by the Police for SD1 and LR vehicles. The 380 is supposed to be its rating in Nm. As above scarce as can be - look for a wrecked TVR or Morgan V8. Re MX5 boxes, they are rumoured to survive with some serious power going through - 4.3L Lexus V8 with 2 Turbos!
 
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