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Donman

Xd alloy head crossflow v Xf crossflow

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Lots more details are needed to make an informed decision but I will have a guess at there will be no difference what so ever if they both need rebuilding.

Information that is needed is

1. Is the XF motor carby or injected?

2. Do you want carby or injected when your done?

3. How fast do you want to go?

4. How much money do you have to spend?

 

The main difference between the motors will be the standard compression ratio. If the XF motor is an injected motor it will most likely have slightly larger valves in the head. Apart from the valves and a couple of accessories that bolt onto the engine both engine are just about identical.

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I had planned on keeping it carby but would it be worth the money converting to efi or would the money be better spent else were

Motor will be getting rebuily

What kind of horse power could be made by throwing $5000 at it

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I heard the xf block are stronger and designed a bit better if theres no significant gain i won't waste my money when i have a good motor already

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All blocks are just about identical apart from the key feature of the 86DA block allowing for the easy installation of an EF falcon full counter weight crank. But since your only spending $5000 don't worry about EF cranks of better blocks just run with what you have especially if it's in good condition. You would need to be spending close on $15,000 on the motor to warrant the EF crank

 

Staying with carby will be much easier, cheaper and will net more horsepower especially with the amount of money you have to spend.

 

Next couple of questions will be

1. Is $5000 just on the motor or everything including gearbox, diff, brakes etc

2. Is the car auto or manual? Do you need to convert the car to your desired choice of gearbox?

3. What diff ratio do you want/have

4.What is the car going to be used for.

 

Don't focus on horsepower cause you wont be able to brag you have heaps, but what you do have is a light car compared to all the newer cars and a very torquey engine that will actually make your car fast.

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Don't underestimate torque on the street.  You can't literally drive anywhere at big revs and speeds, so why not go for something that pulls hard down low and through the mid range where you need it.

 

If you want to drag or race the car totally different story and a few threads on Thor and robs xf will help you there.

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5 grand is just for the motor it is auto and i want to keep it auto. Yes i agree i would preffer torque over horsepower any day the car will just be my weekend cruiser. Was thinking about going the eb diff

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I'm no expert on Ally headed sixes, but 5 or 6 more years of fooked threads, tap water, dodgy mechanics etc... would push me towards a younger engine. Just thinking.....

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If the xd alloy head engine is original it will have an early open chamber head. Good if you want to add boost. Some say they are also good as they don't have efi cut outs. Me I don't agree.

Since your car is an xd I'm guessing the motor will be fairly tired or hi k's. $5000 is going to be eaten up fairly quickly on quality machining of your existing engine. But with some carefull spending you could get a nice torque monster that with good service intervals and quality oil, clean air and fuel etc. will last for another 20 years.

I'd be looking for a c2 or D head for the better chamber shape and bump in compression they offer. After that is just the usual, cam, intake, exhaust and ignition. You can't beat the 6al2 programmable and matching coil for a street application. Especially with map sensor input to help with lean cruise.

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5 grand is just for the motor it is auto and i want to keep it auto. Yes i agree i would preffer torque over horsepower any day the car will just be my weekend cruiser. Was thinking about going the eb diff

Assuming you have an XD it will be leaf spring rear which require either a ute or wagon diff from and EB2 or ED(can ute EF/EL but the handbrake is really simple on the EB2/ED diffs) You will need a E series sedan tailshaft if you have a sedan though as the ute/wagon tailshaft will be longer.

 

As for the power it really comes down to what type of cruiser your after, picking a camshaft that has the operating RPM range you want is the most crucial thing. If you want a highway cruiser don't pick a cam that requires short diff gears unless your happy for the car to rev a bit on the highway and use shit loads of fuel while on the highway. If you want a nice lumpy idle and plenty of go up top pick a cam from lower down the list of the camshaft manufactures below. If your comfortable doing a bit of maintenance then consider a solid cam as it will give you a bit more power compared to the same size hydraulic.

These are just some cam manufactures, have a look at their range as they all offer something slightly different.

http://www.camtechcams.com.au/#

http://tighecams.com.au/

http://www.crowcams.com.au/

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If building one for performance you will swap and change parts anyway so there is no real gain on a lower reving engine as far as blocks go. But if you want to turn it past 6500 the XF block is better as far was you can just drop a EF crank into it under 6000 I would not bother unless it was for a race car or something that sees revs for a while at a time

Heads again you just chop and change to suit what you want and the comp ratio you are looking for. The old XDs have a open chamber one the later ones have a smaler chamber one, some will say some are better then others but other then chambers to suit the comp ratio your looking for there all about the same give or take in a few places

Your budget is decent id consider boost at that budget, mine cost less then that and made some nice numbers and real good TQ at no revs you could do 250 300rwhp with that budget if you can spin the spaners yourself mine runs LPG and I did mine for about 3k but the turbo hotside was 2nd hand but that was cooler piping cooler so on and a LPG system that would support a turbo setup. But as has been said a barra turbo even a stock one will stomp most NA 250s back to the stoneage and is a off the shelf engine you can buy anywhere and it would drive like a new power plant and be good on fuel all the pros of a newer engine but a old school car  

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Biggest cost is the ECU and wiring setup for a Barra.. 

But a Barra Engine is $500 all day long. 4 speed auto about $800 and a good 3.23 or 3.45 LSD about $500 all using 2nd hand parts...

 

182kw stock..... (BA Engine) 190kw stock (BF engine)

 

Better still a 5 speed....

Might need to add some decent rubber too cos this will have no traction at all

 

And it will munch any BA/BF/FG XR6........

1250KG for a XD/F compared to 1750KG BA+

and it also lends itself to a turbo upgrade later if you so wish....

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