Chris Wilson Posted February 6, 2009 Author Share Posted February 6, 2009 I have now ordered the gearbox for this project, initially I was going to get a Pfitzner Performance Gears straight cut dog kit for the stock GTS-t / GTR casing, but the price is now very high and the gear spacing is compromised by using the stock casing, and the shafts and bearing sizes are marginal. I have long been a friend of Nick Cresswelll at Glebe Engineering here in the UK, and they have now got a bespoke six speed sequential transmission that's good for serious torque and horsepower RWD applications, and by the time I add in bearings, seals and labour to modify the stock box, to end up with something that's still H pattern, only 5 speeds and internally compromised there's not a huge price hike to buying something "proper". I have bought, for very very little, 3 auto gearbox bellhousings for the RB engines and will modify one to take a stepped tubular adaptor to mount the Glebe box to, which also allows it sit further back in the tunnel, if space permits, giving a better weight distribution. I don't want to calve the shell up, but you could have the box way back if you modded the sheet metal of the tunnel. The box has 2 drop gears enabling ten minute overall ratio changes, and will be quick release, allowing me to pull the box by undoing a handful of bolts. Beats changing the diff... Pics at http://www.newbury-house.com/glebe/glebe.html If anyone is interested in a serious RWD sequential dog box for their Supra or other application I can maybe arrange a good deal for you, with all the machining done. It's really a race / track day only transmission, and would be horrible on the road. The box on the stand is just a dummy build for measurement and R&D work, a "real" one is in the packing box. They come with a choice of internal ratios, drop gear ratios, a bespoke digital gear position display, gear lever and provision for a gearbox cooler for long distance races. Rear mounts are custom made for the application, as are propshaft flanges. Quote Link to comment Share on other sites More sharing options...
Thorin Posted February 6, 2009 Share Posted February 6, 2009 No response from your website here at the moment Chris, it may just be me. Something I'd love to build (keeping fingers crossed for big redundancy payout ) this year is a caterham/westfield for track usage and have been looking at sequential boxes again. I've never driven one, or any straight cut dog box, I presume you have to blip the throttle on downshift? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 6, 2009 Author Share Posted February 6, 2009 Dunno what's happened to the server, it's not hosted here, but by Gradwell (http://www.gradwell.net) and I have never had this before, guess I just wait and see. Here's a photo in reduced size: Quote Link to comment Share on other sites More sharing options...
Wez Posted February 6, 2009 Share Posted February 6, 2009 Sounds nice Chris, so how much would a Supra setup be? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 6, 2009 Author Share Posted February 6, 2009 You'd have to source a bellhousing from something like a manual Soarer TT, or the 1JZ engine MKIII Supra, and see how easily an adaptor would come together. The box is about 6K, it sounds a lot, but a PPG gear set and mainshaft is about 5K landed and unfitted. Good resale value though, hopefully. Quote Link to comment Share on other sites More sharing options...
Wez Posted February 6, 2009 Share Posted February 6, 2009 When compared to the PPG gear set it is a much better buy Still £6k though Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 18, 2009 Author Share Posted February 18, 2009 I have dummied up an empty casing in the tunnel, hanging off an auto box bellhousing and there are serious clearance issues, meaning I'd have to take the top and part of one side out of the tunnel in the shell of the car, something I REALLY wanted to avoid, cost, time and aggravation wise. I also had further issues (e-mail me if you are seriously thinking of one of these...). All in all I have now rejected this idea, for this application. I have now gone looking at the Swedish made Tractive modular gear boxes (needless to say they are more expensive still...), which are barrel shaped and very customisable. I am sending a bellhousing over to Sweden tomorrow, assuming my polystyrene mock up sits happily in the tunnel, which I am pretty confident it will, and my attempts with an Excel gear ratio file from Tractive and a list of available CWP ratios from Nissan give me a suitable combination. It's things like this that bang up the cost, both in terms of time and in terms of pure money, with such projects. It's also things like this that have you going to the pub to drown feelings of insanity and put questions of "HOW much?", "WHY did I start this?" and "Will it EVER be finished?" out of your mind BTW they are keen to do Supra ones... http://www.tractive.se Quote Link to comment Share on other sites More sharing options...
Jellybean Posted February 18, 2009 Share Posted February 18, 2009 Subscribed, Excellent technical details Chris Everyday is a school day, thanks though will learn alot from this thread may have to read it a few times to digest all the detail Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 18, 2009 Author Share Posted February 18, 2009 Thanks clodola Also did the cam timing, and a careful look at the cam pulley reference marks will show just how far out lining up the dots can be, bearing in mind EVERYTHING is new, and un machined. Left to lining up the dots it would have been quite a lot of crank degrees out on one cam at least. I also checked how much clearance exists if i decide to swing the cam timing on the engine dyno, before anything nasty is likely to occur. I finished the head to sump external drain with a welded in dash 12 boss in the side of the sump pan casting, and it'll be linked to the fitting I made for the back of the head with decent hose. I need to fit the sump tomorrow and get the clearances from the clutch fingers to the back of the bellhousing I am using, so I can see if there's an off the shelf concentric clutch release bearing available to fit the space. Getting rid of clutch arms, external slave cylinders, push rods, pivots et cetera is the way forward, a concentric release transforms pedal effort and linearity, as well as junking a load of hardware. I'll hopefully find something from Tilton will be suitable, the AP ones are VERY expensive and probably not a lot better. I have never had trouble with Tilton ones, anyway, touch wood. http://www.tiltonracing.com/content.php?page=list2&id=264&m=d http://www.gatesgarth.com/sumpandcamtiming/sumpandcamtiming.html Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 25, 2009 Author Share Posted February 25, 2009 Have obtained a couple of auto box bellhousings and a hydraulic concentric clutch release mechanism for the project. I have also bought a Giken triple plate clutch and flywheel assembly (OUCH, the Yen / Pound rate is a *KILLER* right now...). Dummied them all up, taken measurements and Jane has shipped the bellhousing and release assembly to Tractive in Sweden, so they can machine the gearbox front plate to fit the bellhousing and release assembly, which is part of the negotiated price when I ordered the gearbox. Hopefully it'll be done within 2 weeks and I can look at making a gearlever mounting assembly and a rear transmission mount. Looking at getting the wiring finished for the engine to ecu loom soon, and getting the thing ready to dyno. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 25, 2009 Author Share Posted February 25, 2009 These are photos of the auto box bellhousing and the info needed to spec the concentric clutch release cylinder mounting, and the custom input shaft for the gearbox. Someone is doing a similar job fitting a V8 in a MKIV right now, it may help him, I'll find the thread and point him here. Quote Link to comment Share on other sites More sharing options...
SteveR Posted February 26, 2009 Share Posted February 26, 2009 Chris, I'm not sure who you have in mind, but Homer is going to go V8 route at some point, too. Quote Link to comment Share on other sites More sharing options...
Multics Posted June 26, 2009 Share Posted June 26, 2009 This is a great thread Chris, any updates since Feb? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 26, 2009 Author Share Posted June 26, 2009 Sadly not, the ecu loom is done, and a glitch I had with mixing and matching the ignition coils and amp sorted now. It's just time really, the engine and box is pretty much ready to slot in and the rear gearbox mount measured up and fabricated, and then the propshaft. I/C pipework to have made and it should be ready to remove again and map. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 29, 2010 Author Share Posted March 29, 2010 This thing had a base map in it on Friday and runs at last. Need to get some miles on it now, and have the mapping finished. Idles like a pussy-cat at 875 RPM on 280 degree cams May try and get it MOT'd soon. Quote Link to comment Share on other sites More sharing options...
Ryan.G Posted March 30, 2010 Share Posted March 30, 2010 Quote Link to comment Share on other sites More sharing options...
EdMorris Posted March 30, 2010 Share Posted March 30, 2010 Nice job. We need some pics and maybe even some video...? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 30, 2010 Author Share Posted March 30, 2010 Well you know me, I don't do bling, it looks like a bone stock RB26 engine from the outside, it's even having a stock air box, nothing is painted, polished or powder coated either. The only odd thing on the exterior of the engine is no cam position optical sensor and a toothed trigger wheel on the crank. Should go OK though The interior is stock, too, but the gear lever is a bit of a give away! Quote Link to comment Share on other sites More sharing options...
EdMorris Posted March 30, 2010 Share Posted March 30, 2010 All go, no show. The better way to have it I suppose That gear lever is mental! Quote Link to comment Share on other sites More sharing options...
Thorin Posted March 31, 2010 Share Posted March 31, 2010 Handbrake lever is almost as high as the gear lever, don't mistake one for the other Chris! Would be nice to see some in car videos once you get to run it in anger. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 31, 2010 Author Share Posted March 31, 2010 Handbrake lever is almost as high as the gear lever, don't mistake one for the other Chris! Would be nice to see some in car videos once you get to run it in anger. That's because the cables aren't connected to anything at the other end Jeez, I have only just mastered moving on from my box Brownie roll film camera, now he wants video. No can do without buying the kit, I am sadly deplete of stuff like that A ride in it may be possible at a track day? Quote Link to comment Share on other sites More sharing options...
Thorin Posted March 31, 2010 Share Posted March 31, 2010 That's because the cables aren't connected to anything at the other end Jeez, I have only just mastered moving on from my box Brownie roll film camera, now he wants video. No can do without buying the kit, I am sadly deplete of stuff like that A ride in it may be possible at a track day? That would be even better Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 20, 2010 Author Share Posted April 20, 2010 Finally (it's been on the back burner for months and months) I got the thing running on a safe map today. I ran it in on the rollers for 35 minutes (not very long, but time was against me today), then got a rich and modest timing 1 bar map, then a 1.2 bar map. Kept revs to an 8000 RPM max. Should be plenty more to come, this was on elderly Super Unleaded. I was pleased with the curve, I must say. Quote Link to comment Share on other sites More sharing options...
SteveR Posted April 20, 2010 Share Posted April 20, 2010 Looks very driveable - will it still have that sort of shape after a less conservative mapping Chris? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 20, 2010 Author Share Posted April 20, 2010 Should have, yes, it'll just get more boost and more advance. I could have gone for wilder cams really (280 degree with only 10.8 mm lift right now), in hindsight. It idles solidly under 1000 RPM. I think a bit of intake cam advance would bring the boost in earlier. I may try that. Early days. Quote Link to comment Share on other sites More sharing options...
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