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Precision Billet Turbos


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Exact same as mine Noel! Hopefully you get some good results from it

So do I Scott, selection hasnt been easy but I was determined to move away from garret. I'm over their crap.

It will be a while before the car is ready for numbers as i am waiting for some other tasty morsels to arrive but I'm super keen to see what transpires once its all done.

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So do I Scott, selection hasnt been easy but I was determined to move away from garret. I'm over their crap.

It will be a while before the car is ready for numbers as i am waiting for some other tasty morsels to arrive but I'm super keen to see what transpires once its all done.

Its definitely a growing combo Noel, Which head are you running with, 25 or 26?

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Its definitely a growing combo Noel, Which head are you running with, 25 or 26?

call it what you like scot. it began life as a 25 head but its been converted to solid lifter operation to open up cam selection.

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So do I Scott, selection hasnt been easy but I was determined to move away from garret. I'm over their crap.

It will be a while before the car is ready for numbers as i am waiting for some other tasty morsels to arrive but I'm super keen to see what transpires once its all done.

I know an awesome tuner that now loves bolting precisions onto RB's and adding some E85 and some other magic and numbers happen :yes:

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Turbo arrived on the weekend. Interesting physical comparison to the garret 37/88.

Front and rear housings are both smaller and the the precision is considerably lighter but the precision out flows the garret by plenty.

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Turbo arrived on the weekend. Interesting physical comparison to the garret 37/88.

Front and rear housings are both smaller and the the precision is considerably lighter but the precision out flows the garret by plenty.

Exciting times....

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I have some fabrication this week, fitting a 6766 onto a built single cam RB30. Nice looking unit and should flow some air as he is planning to run 35+psi. :)

One thing, these turbo's don't come with rear flanges, and are not a standard 3 inch Vband size, any idea where I can find a Vband for the 4 inch dump at short notice? I really don't want to make one on the lathe, but I will have to if they aren't available locally. Why no flange Precision? :/

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I asked the guy that sold us the turbo, he said 3 weeks from the US, but not to bother as the Precision Vband quality was poor.

I modified a standard ebay 3 inch stainless Vband flange, machining the V smaller and opening up the inside to around 3.25 inch. It works perfectly and seals tight using the aftermarket 3 inch clamp.

As he will be running 35+ psi on a 40mm turbosmart gate, I suggested to use the taller HP cap kit with 35psi spring. There are two kits on their way down from Turbosmart as we speak, the other kit is for me. Let you guys know how well they work. ;)

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hello guys,

for the people that have a precision turbo installed or have installed these in project cars. What size oil feed fittings did you use?

I've searched on google and found people saying -3 AN some say -4 AN and some say -4 AN with a restrictor. So i'm confused as to what i should use.

I have a precision 5857 that i bought long ago and i'm now able to install it and want to know which fittings to use so i dont blow the seals.

Thanks in advance for the help.

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I looked around for this information for a while too, and finally when throwing out the shipping box for the turbo found that the information was actually in the box.

Here I was thinking Precision shipped turbos with no information like Garrett do.

There is an inner and outer box, and al the necessary information I needed was between the two. Tear you box apart and you'll probably find it too, along with stickers etc.

If there is one thing the Precision vbands could do to improve their setup, it would be to make the vband positively centre on the housing by machining a matching edge on the housing and flange. Such a simple thing to do, and it greatly improves the seal, load carrying capability and guarantees pipework is centre off the back of the housing.

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I looked around for this information for a while too, and finally when throwing out the shipping box for the turbo found that the information was actually in the box.

Here I was thinking Precision shipped turbos with no information like Garrett do.

There is an inner and outer box, and al the necessary information I needed was between the two. Tear you box apart and you'll probably find it too, along with stickers etc.

If there is one thing the Precision vbands could do to improve their setup, it would be to make the vband positively centre on the housing by machining a matching edge on the housing and flange. Such a simple thing to do, and it greatly improves the seal, load carrying capability and guarantees pipework is centre off the back of the housing.

Yes have to agree, the V-bands are average and need locating groves

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I looked around for this information for a while too, and finally when throwing out the shipping box for the turbo found that the information was actually in the box.

Here I was thinking Precision shipped turbos with no information like Garrett do.

There is an inner and outer box, and al the necessary information I needed was between the two. Tear you box apart and you'll probably find it too, along with stickers etc.

If there is one thing the Precision vbands could do to improve their setup, it would be to make the vband positively centre on the housing by machining a matching edge on the housing and flange. Such a simple thing to do, and it greatly improves the seal, load carrying capability and guarantees pipework is centre off the back of the housing.

Thanks, i will have a look when i get home later tonight.

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