VH45 turbo placement options...

[Olderthanme]

allrighty...I'm not far away from designing my turbo exhaust manifolds for the VH45DE. I think I'm going to go ahead and plan for twin turbos. Im thinking either twin HY35 turbos or a pair of mitsubishi TD05 turbos. The Mitsubishi ones are physically smaller than the holset turbos but are more expensive.

I'm basically building a 2.25L engine but just two at a time. Twins joined at the hip you may say.500 horsepower is what I'd like to start at... Then have plans for more.

Turbo headers:Made from 304 stainless tubing .10" thick for durability.Flanges from 1/2" or 3/8" thick 304 stainless.JGS 50mm wastegates

I'm going to bottom/side mount the turbos so that they will clear the stock VH starter on the passenger side and the Z steering shaft on the driver's side. That means the passenger side turbo will be shifted forward and the driver's side turbo will be shifted rearward.These pics are taken with a junk Holset H1E for reference

Passenger side turbo that will clear the starter:

Front shot:Rear shot:

Now thankfully the Holset is a little largeer than the Mitsubshi turbos so they would have a little more space. I'd engineer the intake tube for the turbo to pass through the engine mounts so that I can use an air cleaner.Obviously this turbo setup would be pointless for a Q-ship as I'm 86'ing the motor mounts...

I imagine my exhast manifold will look similar to this 4G64-based unit but with different wastegate routing.I think I'd have the center two runers bend up to be longer nd more equal-length.

If there is any interest I'll be making 3 sets of extra headers. These are specifically for a VH45 transplant into a 1970-1978 Datsun Z car but I can make headers off of your blueprints or solidworks sketches for more.

[Olderthanme]

I have considered doing a single turbo mounted either out front (bad for weight distribution...) or: Mounted on top laterally on the car.Both are bulky and have long header tubes.

I believe the more heat you can apply to the turbine wheel, the quicker it will spool. That is why rear-mount turbos are so small or spool late.

The VH just happens to have the little pocket area under the cylinder bank just begging for a set of turbos to sit there...

I'm not willing or have the space to mount the turbos out back. Out front just gets complicated and will reduce the lifespan of the belts and pumps from the raised temperatures in front of the engine.

Serious heat shielding and venting are going to be needed both for the starter and alternator as they are in rather high temperature areas.

[elwesso]

what might be kinda crafty is to just use some square tubing and make a log type manifold.. That would help space and you could mount them back.

[Olderthanme]

I thought about doing some log style headers but I think the tubular ones can be fairly compact and still clear my framerails.There are plenty of different 4 cylinder turbo manifolds to look at for inspiration.I may even do a semi-tubular setup...

[hannibal]

Seems like a good spot to mount them if you have the clearance. BTW, I'm in Fayetteville. I'd love to see your project some time...

Wes, youve been looking at M30 manifolds havent you?

[T45]

I used the stock Q mani's but had clearance issues with the xmember. What I ended up doing was just heating them up and flattening the bottom of the logs to give me the extra 1/4" I needed. Worked great and then I just cut off the pre-cats and welded up the ends of the stock Z mani's to them so they bolt up to the rest of the stock Z system.

Probably not the best for hp but it was really cheap to do and anytime I need an exhaust part I can use any oem or aftermarket exhaust parts for the car.

[craigztoyz]

That is exactly what I plan on. I already cut off the precats, and am planning on having my exhaust guy connect it to the connectors there, and using the 40's mufflers and when i can upgrading the pipes to duel 2 1/2's. You say you had to create a 1/4 of space out of the manifolds, was that on both sides, and after the sheilds where off? How much along the tube did you have to 'dent' I figured it would heat well, and that a soft mallet would do it, in a vise of course. How does the stock pipes flow??? That is what I have been really curious about. mine is a n/a 2+2 w flowmaster 40's. Thanx for the info

[Olderthanme]

Seems like a good spot to mount them if you have the clearance. BTW, I'm in Fayetteville. I'd love to see your project some time...

Sure man!Not much to look at now. Maybe when I have some shiny aluminum sitting around.

T45,Since this is going into a '74 Z... the stock headers would be going right through the middle of the frame rails.

Craigztoyz,The insides of the stock headers are pretty ugly. Globby welds...Here's a pic of mine:

[craigztoyz]

Holy crap!those are the factory welds?

Ugly...

got a pic of the mod on the pipes? any of the adjustments I can do now I will.

My thought is to have the manifolds extended to some connectors at the factory pipes, and swap to high flow cats, and then later at some point upgrade the whole exhaust. On Turbo placement, I'd love to set them in the area below the heads, but thats a lot of heat in that area, so I'd go up front of the motor, as short of piping as possible, sat low for weight.

[T45]

That is exactly what I plan on. I already cut off the precats, and am planning on having my exhaust guy connect it to the connectors there, and using the 40's mufflers and when i can upgrading the pipes to duel 2 1/2's. You say you had to create a 1/4 of space out of the manifolds, was that on both sides, and after the sheilds where off? How much along the tube did you have to 'dent' I figured it would heat well, and that a soft mallet would do it, in a vise of course. How does the stock pipes flow??? That is what I have been really curious about. mine is a n/a 2+2 w flowmaster 40's. Thanx for the info

I ended up taking the shields off and flattened the front half of each manifold, on the bottom, from the front until just after the weld. If you get your engine as low as mine you'll see what you need to do. Also to get some more clearance I heated up the xmember where the mani's hit and made them flat too. There is a small bump in the rear of them that contacted the mani's. This is easiest to do when the engine is out of the Z.

/jack

[craigztoyz]

did you push the engine back at all?I am looking at kicking it back an inch or two, and at possibly lowering the rack a 1/2 inch or so, to get it's top level with the xmember. I hate lowering a rack, lots of welding, and bracing to do it safely, and mildly f'n with the geometry. if you ever are able to post some pics of engine view /clearance of your ride, much apprecieated.

[450zxtt]

hey,good luck on that project olderthanme.wes has a simple answer with the logs.i live in snelville,hope to see you on the road soon.450zxttvh45dett power,baby.

[Olderthanme]

450zxtt,I'd love to come by and see your setup sometime! Where do you live in Snellville? I've been here in Snellville most of my life.What a coincidence! two TT VH45's in the same little town...LOL

Craigztoyz:Yes those are FACTORY welds. What I'd do if I were using the stock manifolds is cut off the bottom half of the "log" and grind everything clean and then just re-weld it back on. (TIG of course)

I have come up with another place to mount the turbos which may be better.

I'll be upgrading the brakes and clutch so I could use one of those trick cantilevered pedal sets that puts the master cylinders inside the car.I could then mount the turbos in the area where the master cylinders used to go on the driver's side, and where the battery was on the passenger's side.


Modified by Olderthanme at 5:08 PM 2/8/2008