I'd be more concerned with beefing up the bottom end of the engine. Where do you think you'll end up on the engine peak torque? I see you had a goal for almost doubling peak HP...bigmankz wrote:Hello there, does anyone know was there ever a Pathfinder on manual transmission with 4 liter gas engine? I know that there are frontiers with 6speed manual. I was wondering if the gearbox off the Frontier will fir Pathfinder? The reason I am asking about as I have a project in my mind to make a turbo pathy. I know wehre to het almsot all the parts need for the project. the only issue is the gear box. I am pretty sure that the stock auto gear box will not be able to handle the power that will be available once the turbos are installed. Manual gear boxes are usually much tougher than autos. What do you guy think/know?
No problem, sounds interesting. I work in the Heavy Duty Vehicle industry (motorcoaches), so have some experience with HD auto trannies. I wonder if you should just try it with the stock transmission. Maybe you can get a Titan or Armada torque converter from the wrecker? I think the transmission would be adaptive, so should continue to work with the new power input. At 380lbft for the V8, the transmission should be able to accept 450lbft at least, I doubt you would exceed that, and if you did, only every so often. Auto tranny would definitely help with all that power, the manual can't be very slick... you don't want to feel like your driving a souped up dump truck!bigmankz wrote:I am not sure about bottom end. I mean I have not seen any stats on what would be the torque. I assume it will be significant as I experienced with my 200SX. I think it will be testing and learning process. My hopes are that the VQ series is usually a very good engine and the crank will hold up to the torque I will have. pistons and rings are no problem. I will also see about rods. It also should not be a problem. There lots of parts for the VQ35 engine and perhaps I can use some of them. I assume Nissan increased the displacement of the VQ40 by having a different crank giving more stroke and perhaps more bore. I also have seen Darton sleevs for vq40 engine which also should help. once installed I am not planning to put as much power as possible from the very begining. It will be a stage by stage process to make sure I will not loose much of reliability of the engine. will go by small steps. The first step would be installing manual and make it work properly with the stock engine. only then will go with the boost. since vq35 is very similar engine I have seen people getting around 400HP at the wheels with whetever torque with completely stock internals. I don't think that vq40 internals will be less reliable.
I also thought of other converter but figured out that playing with different torque converter will be a more expensive procedure that having a manual installed. The cost of the converter is basically a half of the tranny. ANother issue with the auto tranny is that there are no specialists here who could provide programming for the tranny computer.
Electronics part there should be no problem. I will have a custom setup using a system similar to Apexi Power FC. I have some friends who are into rallying and they have lots of experience with their cars and programming of ecu. They achieved some good results and their engines are pretty reliable.
In any case I understand that it will be learning process. But I hope that it will work out well. THe only thing now is to find out whether the maual tranny will fit the engine and where to get it. I checked ebay and they have only 2wd manual available. will keep looking.
thanks for the input.