Sadev sequential @ K-Tec

[PeterGinger]

Has anyone seen this?

http://www.k-tecracing.com/show_product.asp?id=2981

Seems like a good buy. How much do they cost to service, and how often?

 

[BenG]

Apparently they need rebuilding after every few races or around 6K miles on the road, something daft anyways. I read this on Cliosport by the way so make your own mind up...

 

[Sam_K]

Probably not great for just road use though..... its MEGA cool

 

[PeterGinger]

Well I do 8k miles a year, so once a year wouldn't be out of the question. but its down to cost. Do you just replace oil and seals or is it more envolved?

 

[trophymassive]

Its more involved than just changing the oil and seals. The diff is the biggest thing as it is a plate type which will drop off quite quick and loose performance that box has been replaced by the st75-14 box as it is a lot stronger and doesn't have the shift mechanism it the bottom which can cause it to get stuck in gear if shit gets in there a gearbox rebuild will cost anywhere between 500 to 3000 pounds.

 

[George K]

The Sadev is a sequential with a dog clutch engagement system (i.e no synchro)- great for competition, but far from ideal for road use. Correctly matched revs are needed for every change, albeit this can be helped by a spark cut, and you have to work your way down through each gear before starting off, not easy in urban driving, or if caught out on a strange road.

Obviously it has straight cut gears, so is very noisy. Should be quite reliable, but it is very easy to round off the dogs and as already pointed out the diff plates will wear and so lose effectiveness. Would expect to spend £1,000 ish per year on maintenance, excluding removal and re-fitting.

Put it this way we would not recommend using this sort of box on a road car. We are currently doing some work on road going super cars and they are all H pattern synchro (or AMT).

Just a shame the 6 speed box from the Megane or 197 (think that they are the same?) complete with LSD (Megane only)does not fit.

Even going the LSD route or proper traction control (Race Logic) is not cheap. I was agreeably surprised how good the Trophy was even without LSD - in competition quicker with TC off, even in the wet.

 

[PB.283]

It would be cool for about 5 minutes.

But it would give you a lot of performance.

Old cup racers did 0-100mph in around ten seconds due to this gearbox.

Obviously they have a little more power and less weight but not stripping a 172 and adding 20bhp would make it do 10s to 100mph

 

[PeterGinger]

I've never used a sequential box, so have never thought about the differences using one. So from what you say, You can't skip gears say from 2nd to forth or vice versa, like i do sometimes. Also, I didn't realise that there are lots of different versions of the Sadev box. The ST75-14 is the one I was wanting. Say you are coming up to a queue of traffic and break sharply. Can't you just break hard as normal, while at the same time change down quickly through the gears, like in a paddle shift car.Some sequential boxes allow you to drop say three gears in a second. Is this right?

 

[Cue]

sequentials are a right faff on the road - pain in the rectum.

 

[George K]

I've never used a sequential box, so have never thought about the differences using one. So from what you say, You can't skip gears say from 2nd to forth or vice versa, like i do sometimes. Also, I didn't realise that there are lots of different versions of the Sadev box. The ST75-14 is the one I was wanting. Say you are coming up to a queue of traffic and break sharply. Can't you just break hard as normal, while at the same time change down quickly through the gears, like in a paddle shift car.Some sequential boxes allow you to drop say three gears in a second. Is this right?

Yes you can change down very quickly, going through each gear. what a pain doing it all the time in traffic, and even worse if you are caught unawares by a traffic hazard etc.

The racer's 0-100 time is only partly due to the sequential - change time will be about 150-250 millisecs, compared with say 750 for a normal manual - the rest will come from weight, true power output, traction and better ratios. For comparison a good race type semi-auto (AMT) can get down to about 30 ms, and a seamless box is probably about 5 (there is still a bit of a spike on the driveshaft torque read out).

 

[PB.283]

You just said party the box due to speed of change then went on to say ratios, which is the box and power output which is helped by the box too! The atw figure with this box would be approx 10bhp more than a standard box on a 182

 

[Cue]

also factor in that the new box would effect the powertrain losses in terms of bhp.

 

[trophy380]

I've got a dog box in my second car, and although it sounds absolutely awesome and does increase acceleration due to the ratio's, it's not great for everyday road use. I've used it a few times on the road to and from work and although you get some looks from a distance and people thinking 'oh my god what what the hell is that!' it's not great to drive, and lets be honest for everyday road use, your not going to be able to keep the box on song for a short distance. Having to change gear on the rev can be a bit of a nightmare at slow speeds and can seriously damage the dog gears if they don't engage properly.

I use my second car mainly for track days, hillclimbs and the occasional rally, so if your thinking of buying one for motorsport then it's ideal. The straight cut gears are much stronger than helical cut ones, dog box arrangements are stonger than standard synchro types, ratio's are better for acceleration, noise is awesome but service costs can be high and are needed regularly. So personally I would stay well clear if it's only going to be used for road use.

 

[PeterGinger]

How about changing the ratios of the standard box to match the sadev box?

 

[trophy380]

How about changing the ratios of the standard box to match the sadev box?

You could if you could source the parts. A better option would be changing the final drive 'crown wheel and pinion'. I'm not sure what's in the Trophy? But if you were to change this then it would most definitely alter the acceleration, however you would loose top end and would find that you would need to change up quicker. The Trophy may run out of revs very quickly with a lower crown wheel unless the rev band is opened out.

 

[PeterGinger]

Thats what i want lol. 0-100mph as quick as poss. :lol:

 

[trophy380]

I guess if that's what you want then it may be a good option for you! ;o) Ideal for the drag strip!! I'm pretty sure that the clio uses the same diff as the mini cooper s and some citroens / Peugeots and possibly mg's zr etc, but I may be wrong. If this is the case then it will make your search a lot easier.

 

[PeterGinger]

there is always a quaife lsd, but they cost £1k. Would that help or not?
About widening the rev band, do you mean increase the rev limit?
That is bad for the engine and/or very expensive.

 

[trophy380]

Yes increase the rev limit, as it would get through the rev range very quicker with a lower final ratio, so revving to 6,800 would probably need increasing slightly to make the most of this mod. An LSD will help put power down and give you more grip but again it's down to the final drive used on the LSD which alter's the acceleration. None of this should damage the engine, that would only be down to the user! ;o)

 

[PeterGinger]

how would the user fubar the engine? thats probably me lol. I thought putting very wild cams and raising to 8 or 9K revs is mobile grenade territory?