Phil Reade Posted October 9, 2007 Report Share Posted October 9, 2007 Hi, I was looking for an oil additive before starting a 3,000 mile round trip to Almeria Spain (which I've now completed) and saw a very impressive demo done by a vendor of Activ8 at a local car show. It appeared to out-preform all of the alternative popular brands. I added the specified amount to my engine before setting off and it has preformed brilliantly, none of the usual rocker mechanical noises on start-up before oil pressure etc, and the engine does seem generally happier. However, I bottled out putting any in to the gearbox because I didn't trust the manufacturers claims "Avtiv8 can be used on motorcycles with wet clutches or vehicles with overdrives as long as the drive surfaces are mineral and not metal to metal". Given the difference made to the engine I would love to put some in the gearbox to reduce some of that mechanical noise! Is anyone out there running with Activ8 in their gearbox?, with or without overdrive? if so, how has it preformed? Regards Phil 63 TR4 Quote Link to post Share on other sites
ianc Posted October 11, 2007 Report Share Posted October 11, 2007 Hi,I was looking for an oil additive before starting a 3,000 mile round trip to Almeria Spain (which I've now completed) and saw a very impressive demo done by a vendor of Activ8 at a local car show. It appeared to out-preform all of the alternative popular brands. I added the specified amount to my engine before setting off and it has preformed brilliantly, none of the usual rocker mechanical noises on start-up before oil pressure etc, and the engine does seem generally happier. However, I bottled out putting any in to the gearbox because I didn't trust the manufacturers claims "Avtiv8 can be used on motorcycles with wet clutches or vehicles with overdrives as long as the drive surfaces are mineral and not metal to metal". Given the difference made to the engine I would love to put some in the gearbox to reduce some of that mechanical noise! Is anyone out there running with Activ8 in their gearbox?, with or without overdrive? if so, how has it preformed? Regards Phil 63 TR4 In 1964, I bought my second TR2, and it had a recurrent noise from the back axle when cruising the M1 at 100 (4200 rpm). I put Molyslip into the back axle and the noise disappeared completely - I enjoyed 5 years and more than 60,000 miles of quiet running. However, don't put any such juice into the rear axle if you have a limited slip differential! As to the overdrive - it depends whether you believe the manufacturer. If the claims proved wrong, you would have a major problem, as the lining of the overdrive clutch might by then be coated &/or impregnated with the stuff. Ian Cornish Quote Link to post Share on other sites
Phil Reade Posted October 16, 2007 Author Report Share Posted October 16, 2007 Hi Ian, Thanks for the advice about the LSD! Incidentally, I called an Overdrive repair specialist who said the friction clutches within the o/drive are mineral and would not be effected. He said however, there might be a problem from within the g/box itself because the method of holding a selected gear is made by a series of ball bearings sitting in a metal tray or channel, relying on friction to stop "jumping out of gear". I must say, I am surprised no-one from the forum has replied to say they have had any sort of experience using anti-friction additives in the gearbox over the years. Phil Quote Link to post Share on other sites
ianc Posted October 17, 2007 Report Share Posted October 17, 2007 Hi Ian,Thanks for the advice about the LSD! Incidentally, I called an Overdrive repair specialist who said the friction clutches within the o/drive are mineral and would not be effected. He said however, there might be a problem from within the g/box itself because the method of holding a selected gear is made by a series of ball bearings sitting in a metal tray or channel, relying on friction to stop "jumping out of gear". I must say, I am surprised no-one from the forum has replied to say they have had any sort of experience using anti-friction additives in the gearbox over the years. Phil Possibly the lack of replies indicates that so many TRs are fitted with overdrive, and a "molyslip" type of additive would render the overdrive useless. It is possible that a different sort of additive, such as the one you have described, might work, but who is going to be the first to try it? To say that friction is what prevents the car jumping out of gear is not true. With straight-cut gears, such as are found in vintage cars without synchromesh, there is no end force exerted in the box. With our boxes, the force exerted by the gears, either in drive or over-run (depending which gear is selected) will try to force the gears into or out of engagement, and the spring force exerted within the synchro mechanism must be sufficient to withstand this end force. In times gone by, when gearboxes were clapped out (e.g. by the end of WW2), cars did jump out of gear, so drivers got used to using the left knee to hold the car in gear - especially important when descending a hill using engine braking, as the drum brakes alone couldn't cope! Ian Cornish Quote Link to post Share on other sites
MikeF Posted October 21, 2007 Report Share Posted October 21, 2007 Hi Phil, I tried pretty much everything that was on the market at the end of the '60s in terms of additives - as in looking to achieve that split-second faster gearchange and/or overdrive engagement. In a straight gearbox, favourable result could be achieved . . . In an overdrive gearbox . . . let's just say I trashed every o/d unit I ever experimented with. Technology may well have moved on . . . but I'd like a copper-bottomed warranty ! Cheers, Alec Memories! Agree, back then completed the last few miles of rally stage near oil free with moly in engine, but ruined o/d with it in gear box Mike Quote Link to post Share on other sites
Phil Reade Posted October 24, 2007 Author Report Share Posted October 24, 2007 Hi Ian, Alec & Mike, Thanks for your input, I value your advice! I must say Active8's gearbox & overdrive claim does need a lot more supporting evidence, given the consequences should the claim prove to be flawed. I might take it up with them, their website does invite users to provide testimonials. Kind Regards Phil Quote Link to post Share on other sites
Allan Westbury Posted October 24, 2007 Report Share Posted October 24, 2007 Hi,I was looking for an oil additive before starting a 3,000 mile round trip to Almeria Spain (which I've now completed) and saw a very impressive demo done by a vendor of Activ8 at a local car show. It appeared to out-preform all of the alternative popular brands. I added the specified amount to my engine before setting off and it has preformed brilliantly, none of the usual rocker mechanical noises on start-up before oil pressure etc, and the engine does seem generally happier. However, I bottled out putting any in to the gearbox because I didn't trust the manufacturers claims "Avtiv8 can be used on motorcycles with wet clutches or vehicles with overdrives as long as the drive surfaces are mineral and not metal to metal". Given the difference made to the engine I would love to put some in the gearbox to reduce some of that mechanical noise! Is anyone out there running with Activ8 in their gearbox?, with or without overdrive? if so, how has it preformed? Regards Phil 63 TR4 Hi, Am I the only one? I bought some Activ8 for my TR4A at the International in either 05 or 06 cannot remember which, having also seen the 'magic' demo. I put into the engine first with no probs & added to the rear diff & gearbox with overdrive last winter. Have done 3-4000 miles this year including the european in Rimini. The gearchange is definitely significantly smoother & quieter & whereas a quick change down in overdrive could produce a crunch before, this has also improved quite markedly. To date I would have to profess to being 100% satisfied. cheers, Allan Quote Link to post Share on other sites
Phil Reade Posted October 26, 2007 Author Report Share Posted October 26, 2007 Hi,Am I the only one? I bought some Activ8 for my TR4A at the International in either 05 or 06 cannot remember which, having also seen the 'magic' demo. I put into the engine first with no probs & added to the rear diff & gearbox with overdrive last winter. Have done 3-4000 miles this year including the european in Rimini. The gearchange is definitely significantly smoother & quieter & whereas a quick change down in overdrive could produce a crunch before, this has also improved quite markedly. To date I would have to profess to being 100% satisfied. cheers, Allan Thanks for the info Allen! All the best Phil Quote Link to post Share on other sites
ianc Posted October 27, 2007 Report Share Posted October 27, 2007 If changing out of overdrive, the throttle should always be open, so as to avoid jarring the transmission - big Healeys had a throttle switch which prevented overdrive being disengaged when the driver's foot was not depressing the pedal sufficiently. If you used to get a jarring when changing out of overdrive it suggests that you were not doing so with the throttle open (you need only blip the throttle as you flick the switch). So, if you are no longer getting this jarring (and you haven't changed your technique), then it suggests to me that the jungle juice has made the overdrive clutch slip - and that is not what you want. If you are worried about blipping the throttle whilst decelerating, fit an extension to the throttle pedal so that you can heel and toe (you may need to bend the throttle pedal backwards a little to achieve the right position for this). Basically - engaging or disengaging everdrive, the throttle should be open (fully open when engaging overdrive) - that way, you'll get a nice smooth change. Ian Cornish Quote Link to post Share on other sites
BrianC Posted October 28, 2007 Report Share Posted October 28, 2007 One of the interesting effects of having TRs back on the road after such a long period is that I seem to have subconsciously returned to blipping the throttle on down-shifting through the normal gears. Perhaps it's beome a dormant instinct from my earlier life, but I don't do it when driving the everyday modern cars. (Or it could just be that I love the noise it makes ). I must check to see to whether I am also doing it when switching out of overdrive. Quote Link to post Share on other sites
Allan Westbury Posted October 28, 2007 Report Share Posted October 28, 2007 One of the interesting effects of having TRs back on the road after such a long period is that I seem to have subconsciously returned to blipping the throttle on down-shifting through the normal gears. Perhaps it's beome a dormant instinct from my earlier life, but I don't do it when driving the everyday modern cars. (Or it could just be that I love the noise it makes ). I must check to see to whether I am also doing it when switching out of overdrive. Hi Ian, As a 'learner' I was taught to double-de clutch & normally do in the TR. The only time I get caught out is when I am pushing on a bit & go for a quick change, forgetting I am in overdrive. I accept that 3000 miles is not enough to prove anything either way, but first indications are good. I will report back after next years trip to Sweden as to how I feel then! Back on the topc of double-de-clutching I recently had an awsome Classic car track day driving a Mk 2 jag, e-type, DB6 & D type jag. I tried to double-de-clutch & just did not have time. the instructor told me not to bother, just to crunch the gears, the same as everyone else did! Quote Link to post Share on other sites
ianc Posted October 29, 2007 Report Share Posted October 29, 2007 True double-declutching, as my Uncle had to do on his 1925 3-litre Bentley (a notoriously difficult box for making clean changes), is a slow process and not truly necessary if there's still some life left in the synchromesh. However, a "halfway house" approach does save some of the crunching when changing down in older vehicles: just blip the throttle as you depress the clutch. I think that it accelerates the gearbox input shaft somewhat and I find it makes for a cleaner change (less likelihood of a crunch). I sometimes use the technique on modern vehicles, too. My wife's Citroen AX tends to crunch when changing from 1st to 2nd, but if I bother to double-declutch, it just snicks in. Ian Cornish Quote Link to post Share on other sites
Phil Reade Posted October 30, 2007 Author Report Share Posted October 30, 2007 If changing out of overdrive, the throttle should always be open, so as to avoid jarring the transmission - big Healeys had a throttle switch which prevented overdrive being disengaged when the driver's foot was not depressing the pedal sufficiently. If you used to get a jarring when changing out of overdrive it suggests that you were not doing so with the throttle open (you need only blip the throttle as you flick the switch). So, if you are no longer getting this jarring (and you haven't changed your technique), then it suggests to me that the jungle juice has made the overdrive clutch slip - and that is not what you want.If you are worried about blipping the throttle whilst decelerating, fit an extension to the throttle pedal so that you can heel and toe (you may need to bend the throttle pedal backwards a little to achieve the right position for this). Basically - engaging or disengaging everdrive, the throttle should be open (fully open when engaging overdrive) - that way, you'll get a nice smooth change. Ian Cornish Hi Guy's, I also found it tricky switching the overdrive off under power when at the same time slowing down. You might be interested in this method I now use! I Leave the overdrive on when I change down to third, which usually makes me slow enough for most things, then flick it off when I reapply the power in 3rd o/d, it works a treat! Cheers! Phil Quote Link to post Share on other sites
ianc Posted November 1, 2007 Report Share Posted November 1, 2007 I found that moving from one gear to another without de-energising the overdrive almost always jarred the transmission as, with the gear lever moving across the gate, the overdrive went from engaged to disengaged then back to engaged - so I tried to avoid this. If you find it difficult to brake and change out of overdrive without jarring the transmission, consider fitting a Revington Overdrive Logic Box - that will disengage the overdrive as soon as you move the gear lever to neutral. It also prevents the embarrassment of shifting from 1st gear and finding yourself in overdrive 2nd, with the engine unwilling to pull at the lower than expected revs. I described this box of tricks in TRaction 203 (May 2005), and continue to be glad that I fitted it. As far as I am aware, no one else makes a similar product. Ian Cornish Quote Link to post Share on other sites
Rhodri Posted November 1, 2007 Report Share Posted November 1, 2007 I think "Tim Trinda" sells his own similar type on ebay. Quote Link to post Share on other sites
mart160plus Posted November 13, 2007 Report Share Posted November 13, 2007 I tried pretty much everything that was on the market at the end of the '60s in terms of additives - as in looking to achieve that split-second faster gearchange and/or overdrive engagement. The swinging 60s eh ? You talking about the cars or yourself ??!!! ;-p Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.