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Just wondering if someone could help me out, my V35 250GT Sedan is starting to consume about a litre of oil a week and blowing out large amounts of white smoke so it looks like time for a new engine.

I'm considering a VQ35DE from a 350GT Coupe as I can't find a 2.5 litre and not sure if it's a direct fit? Is there much work involved?

Thanks.

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I just asked the same question but for a 300GT, apparently it's a straight swap, you just need a new ECU from the 3.5 model and that the gearbox is the same as the 300GT, not too sure about the 250GT though. I'm just gonna get the whole car instead, since I want a manual hahah

Edited by itsRICHARD

Yeah, you'll need not only the motor, but the loom, and relevant ecus. Don't know if the 35 ecu will talk to the 25 tranny ecu. Might just be a plug in, may be a wire in.

To me it sounds more like a head gasket issue, and may not be as expensive as you think. There are spare motors around.

I just asked the same question but for a 300GT, apparently it's a straight swap, you just need a new ECU from the 3.5 model and that the gearbox is the same as the 300GT, not too sure about the 250GT though. I'm just gonna get the whole car instead, since I want a manual hahah

I've had the valve seals changed and the mechanic who replaced them seems to "think" the head gasket is fine.... Can you recommend anyone selling a 25 engine?

I think nisswreck had a vq25dd stagea for wrecking, but it's been a while since I looked on their site. Also Scotty nm35 has a 25DD, but I'm not sure if its for sale. You can shoot him a pm.

The 250GT has a four speed box VS the 5 speed in the 3/3.5lt models. So you may need a new box and as said before all relevant looms and ecu. Most people are telling me this route for ease of forced induction

its difficult to upgrade the motor...

the ECU controls the motor and the dashboard

The TCM controls the trans

The trans needs to have the right instrument cluster for gear display

so in theory, the whole lot needs to be changed

its as easy as doing a V8 conversion

its difficult to upgrade the motor... the ECU controls the motor and the dashboard The TCM controls the trans The trans needs to have the right instrument cluster for gear display so in theory, the whole lot needs to be changed its as easy as doing a V8 conversion

What about the VQ25DET? Is this the same as the VQ25DD? Because I can see both on eBay

If so, what's the complications around installing this turbo engine into the car?

Cheers

Where I'm at at the moment is I can see a cheap VQ25DET on eBay with loom, withoute ECU and can see a VQ25DD ECU for sale separately, are they compatible?

What's the difference between the two engines?

Nope, not compatible.

VQ25DD - Non turbo, DIRECT injection motor

VQ25det- Turbo, std type injected motor.

You can pick up a VQ25det std ECU easy enough, but then you have to do all the intercooler and turbo plumbing as well, upgrade your gearbox and make the ECU talk to it too.

If you feel like being a trail blazer, go for it. But expect a lot of trouble shooting.

Damn, that sucks to hear..

So back to square one and look for a non turbo engine, is the 25DD engine comptabible with 25DE ECU?

My stock engine was a DE and theres a few cheaper options without loom/ecu etc for sale.

its always going to be a major job. electronics. if you like stripping your car down to a bare shell - meaning: taking the driveline, dash, loom all out and start from scratch.... do it.

you could probably get the 2.5 rebuilt and modded using turbo internals and bolt ons... keeping all the VIN numbers matching... for a bit more $

hell you would almost be better off dropping in an SR20DET blacktop and 6 speed...

Edited by Deep Dish V35

Damn, that sucks to hear..

So back to square one and look for a non turbo engine, is the 25DD engine comptabible with 25DE ECU?

My stock engine was a DE and theres a few cheaper options without loom/ecu etc for sale.

If you have a V35 250GT, the stock engine is a VQ25DD, not a DE.

its always going to be a major job. electronics. if you like stripping your car down to a bare shell - meaning: taking the driveline, dash, loom all out and start from scratch.... do it.

you could probably get the 2.5 rebuilt and modded using turbo internals and bolt ons... keeping all the VIN numbers matching... for a bit more $

hell you would almost be better off dropping in an SR20DET blacktop and 6 speed...

VQ25dd uses the same rods as the VQ25det so no issue there. Can't imagine that the studs/bearings etc would be different.

The DD is an interesting engine, I have some big power planned for the one I have here. I don't think a set of forged pistons will help it much though, I will be leaving the engine stock and running ethanol.

A lot of thought went into the direct injection and chamber design, the piston has a very interesting shape. Half the siamese port intake runners are cut on cruise also, to promote swirl. It will need plenty of custom work to get any power out of it, NA or FI.

The engine is similar to the VQ25det electrically, it even runs the same ecu plug (so the Fcon Vpro may work). The main difference is the fuel system, a high pressure fuel pump runs off one of the camshafts with ecu pressure feedback.

post-63525-0-19317000-1350906516_thumb.png

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