Jump to content
SAU Community

Recommended Posts

Just thinking out loud here.

The idea is to fit a VQ25DET into a C34

Why?

Something different

Prefer to run as manual RWD. Easier to do engine and gearbox driveline conversion

Target 250-300rwkw......can they make this much :woot:

I need to do some reading up on Vq25det mods etc.

I have 10 years Rb experience....no VQ25 knowledge

Main issues to work out

1. Pretty sure it will fit in between strut towers. Engine mounts to fab

2. ECU wiring issues....Do people have VQ25det wiring diagrams they can flick a copy to me?

Should I go stand alone ecu and be able to tune it than work with factory VQ ECU?

3. What manual RWD gear box and clutch etc.....All 350Z, V35 skyline stuff?

Any cheap gearbox options, but as strong?

4. Basic connection problems of water, intercooler, exhaust, intake etc.

Link to comment
https://www.sau.com.au/forums/topic/413655-installing-a-nm35-vq25det-in-a-c34/
Share on other sites

  • Replies 61
  • Created
  • Last Reply

Top Posters In This Topic

Here is a VQ35HR into a 32 GTR. Going by the pics there is enough room to fit it between the towers, etc. I think the way he's done some stuff is a little naff, but it works.

http://zilvia.net/f/builds-builds-only/346234-retarded-vq35hr-r32-skyrine-build-20.html#post4842144

and first page is here.

http://zilvia.net/f/builds-builds-only/346234-retarded-vq35hr-r32-skyrine-build.html

Vq25det is already turbo. So compression is right, turbo manifolds etc

Can get a vq25det front cut for $1000

sell rb25det

vq35 is non turbo......add turbo or supercharger kit plus to buy engine equals $10K plus...

$ verse cents really

tring to keep to a cheap budget build

VQ35 will be easier from an engine management standpoint, controlling throttle, cams, etc.

Anything can be done with enough time and/or money.

I'd be doing VQ35 with VQ25 heads, and I think the turbo manifolds then bolt up?

Agree

Target 250-300rwkw on the vq25det...... fit a bigger turbo and injectors and fmic exh....easy.

Ecu is main issue

Neo Rb25det.....Nistune ecu....cheap good workable solution

VQ35 will be easier from an engine management standpoint, controlling throttle, cams, etc.

Anything can be done with enough time and/or money.

I'd be doing VQ35 with VQ25 heads, and I think the turbo manifolds then bolt up?

The VQ25det manifolds bolt up to the VQ35de heads.

Just drop it in with either a 350z/V35 6 speed box or a 300zxTT box and adapter plate. You would be best getting a standalone ecu, Link, Vipec or Haltech but there are cam actuation issues to work through.

Vq25det is already turbo. So compression is right, turbo manifolds etc

Can get a vq25det front cut for $1000

sell rb25det

vq35 is non turbo......add turbo or supercharger kit plus to buy engine equals $10K plus...

$ verse cents really

tring to keep to a cheap budget build

Yeah fair enough, remember though that an m35 front cut, at least in australia, wont have a manual gearbox. I'm guessing that a 350z gearbox would be the best one to use, no idea what sort of price they go for though

The VQ25det manifolds bolt up to the VQ35de heads.

Just drop it in with either a 350z/V35 6 speed box or a 300zxTT box and adapter plate. You would be best getting a standalone ecu, Link, Vipec or Haltech but there are cam actuation issues to work through.

Who makes the gearbox adaptor plates?

off the shelf or custom made?

Cam actuation....do mine like VCT?

Most aftermarket ecu's have a trigger to turn on and off

I suppose its not on/off, but varible

I had a similar issue once with a motec M4 on a black 20V 4age

I might grab the VQ anyway....workout the issues later

Can always sell it again if I do not use it or if its too hard

The adapter plates are made over in Perth somewhere, have a read of this thread...

http://www.skylinesaustralia.com/forums/topic/358412-z32-300zx-with-vq30-twin-turbo-conversion/

He will know where they came from...

As for the cams, they are constantly variable giving around 40kw more midrange in my car and making the turbo much more responsive. Well worth keeping the evct if you can, I know Trent (Status) got the Link G4 to work with a similar Vcam RB26 setup which proved it was possible, I guess you need to find a good tuner that doesn't mind experimenting.

Heres a crazy idea that could just work. If u could find a crashed navara with a manual vq40 in it, you might have a cheap way to do it. If you stayed NA for now you could convert with all the oem ecu and stuff. Even NA would b pretty good in a stag with the mountain of torque from 4 litres. No need for head swaps, sump changes or adaptor plates. Then just build it with a turbo later.

Engine fits between strut towers....done before in 32, 34's

Did not think about the AWD sump issue....thanks

So the RWD gearbox will not mate up with the AWD sump.....

The VQ25det alloy block should be lighter than the Rb25 cast iron block....right?

The stagea will be RWD, as lighter than AWD, plus the body will be a fair bit light too :whistling:

So might end up closer weight to a skyline coupe.....should make handling a bit better.

Thanks Scott for info

Well.....I bought a 80-90% complete damaged M35 2001 today....

I will strip it, sell off the parts I do not need and keep the motor....for something

Spoke with Mercury today

They are building a M35 Stagea with a Trust T78 and 6 spd 34 GTR box behind it

It all mounted in the car.....still AWD

Might go check it out tomorrow for a look

Spoke with Mercury today

They are building a M35 Stagea with a Trust T78 and 6 spd 34 GTR box behind it

It all mounted in the car.....still AWD

Might go check it out tomorrow for a look

We've been discussing this build. Take some pics for us if you can.

Interesting time starting for you by the sounds of it :thumbsup:

  • 2 weeks later...

If I go the VQ25det with a 6spd V35 box I will have to sort the speedo out as the C34 runs off the gearbox and the M35/V35 runs off the rear wheels

How do you do this in a C34???

The V35 6 spd is the same price ($1000) as a good R33/R34 RWD box. But the R34/R34 box needs a very expensive adpator to make it to bolt upto the VQ, but the speedo would be sorted.

Fould some VQ35 to Rb gearbox adaptors on US ebay for $1150 plus postage. Have not found a aussie one yet to compare price

Maybe cut and weld the bell housing like Mercury did on the R34 GTR box in the M35 would be cheaper....

Why can't I keep the VQ25det AWD sump? Do I have to change it to a RWD sump?

In 2 weeks I will have both the C34 and M35 cars to compare and probably answer some of my own questions.

Edited by darrinspencer

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Hi, is the HKS  Tower Bar still available ? negotiable ? 馃
    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
  • Create New...