xbcool 351 Posted July 12, 2016 gday trendsetters my new motor is all but finished being built and now the gearbox delima is about to start, motor is a windsor based dart block with clevo heads hoping for around 700fwhp. I've been in contact with the bloke I'm getting to build a box and he suggested a t400. I'm not against this idea given that they are bullshit strong and the c4 do have limitations I currently run a c4 in my xb it makes around the 550fwhp mark and have had no issues and it still shifts as an auto not a full manualised box the builder I'm using says this one will need to be full manual ,but a t400 can stay as an auto. I'm open to suggestions and advice as I am yet to buy a convertor or tailshaft and exhaust can be massaged if necessary thanks in advance steve Share this post Link to post Share on other sites
bear351c 10,273 Posted July 12, 2016 Hey Steve, good to hear to new "Clevor" is ready. Can't help with the 'box, never had a 700HP engine.!! Did you want to stay auto shift or willing to shift manually.? I've heard amazing things can be done with C4's or even Powerglides. Share this post Link to post Share on other sites
xbcool 351 Posted July 12, 2016 Yep the motors been a slow process Yep awesome thing can happen with c4s I'd prefer to have auto shift I'm not too concerned with me driving it but my Mrs. Will need to drive occasionally and I'm worried she'll stick it in d and burn the box out I'm hoping gregaust drops in to offer some advice Beauty is only skin deep Ugly goes all the way to the bone Share this post Link to post Share on other sites
gregaust 319 Posted July 12, 2016 Did someone call? What's the reasoning for wanting manual VB? Vacuum for shifts ? or line pressure ? A manual valvebody is likely the easiest way , gives full pressure and no dramas with vacuum for shifts . Auto shift can be done although can be tricky to set up , depending on cam size and engine vacuum Waht's the plans for use ? Street mostly or race only ? Share this post Link to post Share on other sites
xbcool 351 Posted July 12, 2016 welcome gregaust car will be used 50/50 street/strip and the reason for wanting a box with vacuum is my missus will drive this car and I think she'll have trouble understanding that it has to be shifted manually. I fear the car will be left in d and burn the box out cams not massive and I'm unsure of engine vacuum as it's yet to be run Share this post Link to post Share on other sites
CHESTNUTXE 7,332 Posted July 13, 2016 keep the c4 behind it and mod it. Share this post Link to post Share on other sites
gregaust 319 Posted July 13, 2016 Well you could go something like a Transgo kit , set up right it can work . The "Race" pressure spring they give you does give around 200 psi pretty easy as vacuum drops. Another option could be a PTC valvebody . They do an auto shift "ATB" (all time boost), what that does is gives line pressure similar to a manual valvebody as opposed to modulated line pressure . It does still use a vacuum signal to shift although i seem the remember something that you might be able to run without the vacuum , although i've not tried . Have to check on that . . I'm using one in one of my own trans seeing plenty of power It does space the shifts slightly more than a normal valvebody but i like it. A few other mods it will hold up IMO Share this post Link to post Share on other sites
xbcool 351 Posted July 13, 2016 thanks gregaust I'll have a chat with the builder steve Share this post Link to post Share on other sites
