Title: Close ratio grey crashbox Post by: Gary C on August 30, 2016, 04:23:00 PM Just wondering if anyone has used Old Car Gearboxes in Moorabin for a taller 1st and 2nd gear upgrade in their grey powered race cars?
Or for that matter where to purchase the gear from, I have a mate in WA been waiting a long time for his. Also the hassle of sending a box from WA to Moorabin. Thanks, Gary Title: Re: Close ratio grey crashbox Post by: Gary C on September 08, 2016, 06:23:10 PM C'mon Harv.
Title: Re: Close ratio grey crashbox Post by: weddo on September 09, 2016, 08:05:20 PM Gary, check with Ellis French on face book he is building a close ratio box at the moment.
regards Weddo Title: Re: Close ratio grey crashbox Post by: Harv on September 10, 2016, 12:45:07 PM C'mon Harv. Sorry, got distracted by work :(. Haven't seen the grey crashie modified this way before - most of the mods I've seen have been replacements (with adaptor plates) for other boxes, for example: a) Riley 2.5. It had a 4-speed manual overdriven transmission with the following ratios (the respective grey motor crashbox values are in brackets): 1st gear 12.93:1 (2.99:1) 2nd gear 8.03:1 (1.59:1) 3rd gear 5.6:1, or 4.11:1 in overdrive (1:1) 4th gear 3.9:1, or 2.87:1 in overdrive Reverse 17.52:1 (2.99:1) Even with the change in diff ratio (the Riley had 4.1:1 compared to the old grey motor at 3.89:1), this is a pretty torque-oriented gearbox. I assume that bolting one to a grey would have been for hillclimbers rather than those chasing top-speed. b) BMC B-series. This is probably not the three-speed crashbox fitted to the Wolseley 24/80/Austin Freeway, but likely the four-speed all-synchro offered on the Marina. The Marina gearing is shown below (the respective grey motor crashbox values are in brackets): 1st gear 3.412:1 (2.99:1) 2nd gear 2.12:1 (1.59:1) 3rd gear 1.43:1 (1:1) 4th gear 1:1 Reverse 3.753:1 (2.99:1) Note that the Marina box has the same top-end capability, but is lower geared in 1st gear. c) Datsun 1600. The Datsun gearbox was either a four-speed manual (the F4W63L and F4W63L gearboxes) or five-speed manual (the FS5W60L and FS5W63A gearboxes). I’m assuming most people were chasing the five-speed manual, which had a top gear ratio of some 0.85:1 compared to the grey motor crashbox at 1:1. d) Jag. Cheers, Harv |