How much boost or spool time am i losing if my turbo isnt as close to the exhaust ports as possible?

[Fantastika]

Im considering a different turbo, but that would require an adapter to go from the stock manifold to the new turbo, and im not really keen on making a new manifold. It would be about a 10cm extra pipe, i could wrap it in exhaust wrap to prevent heat loss

 

[mudgudgeon]

Which vehicle/ engine/ turbo?

It's impossible to say 'how much'.

Lots of adaptors are less than 10cm.

Best to keep it as short as possible. But i don't see an extra 10cm being a huge problem.
Will the extra length cause clearance issues? For turbo? or exhaust? or intake?

 

[Fantastika]

Which vehicle/ engine/ turbo?

It's impossible to say 'how much'.

Lots of adaptors are less than 10cm.

Best to keep it as short as possible. But i don't see an extra 10cm being a huge problem.
Will the extra length cause clearance issues? For turbo? or exhaust? or intake?

This is the adapter prototype out plastic, it's a 2ltii and the turbo is a gt2052

 

[FJBen]

Im considering a different turbo, but that would require an adapter to go from the stock manifold to the new turbo, and im not really keen on making a new manifold. It would be about a 10cm extra pipe, i could wrap it in exhaust wrap to prevent heat loss

I’m not sure you will be able to tell any difference. Swapping to a different turbo changes response and everything as well so you really have zero baseline to go off of.

 

[mudgudgeon]

This is the adapter prototype out plastic, it's a 2ltii and the turbo is a gt2052

View attachment 3520059

Looks pretty sweet.

Are you going to fabricate? Or machine A billet?

How thick are the flanges on your model? I reckon keep them around 10mm or more thick to ensure sealing of gaskets

I think you could shorten the whole thing quite a bit with a bit of R&D if you want to reduce possibility of lag.

A couple of suggestions.
- Use shorter studs, and shorten your adapter. You only need enough room to get nuts and wrench inbetween top and bottom studs.

- use different hardware.
- Swap studs for bolts.
- reverse the orientation of studs. Thread studs into adapter, and secure adapter to manifold with nuts. Secure turbo to adapter with nuts.
- Or a combination of the above.

A few random pictures of different arrangements. Some might not be possible depending on clearance to castings, clearance to swing wrenches etc

 

[Fantastika]

Looks pretty sweet.

Are you going to fabricate? Or machine A billet?

How thick are the flanges on your model? I reckon keep them around 10mm or more thick to ensure sealing of gaskets

I think you could shorten the whole thing quite a bit with a bit of R&D if you want to reduce possibility of lag.

A couple of suggestions.
- Use shorter studs, and shorten your adapter. You only need enough room to get nuts and wrench inbetween top and bottom studs.

View attachment 3520392

- use different hardware.
- Swap studs for bolts.
- reverse the orientation of studs. Thread studs into adapter, and secure adapter to manifold with nuts. Secure turbo to adapter with nuts.
- Or a combination of the above.

A few random pictures of different arrangements. Some might not be possible depending on clearance to castings, clearance to swing wrenches etc
View attachment 3520393View attachment 3520394View attachment 3520395

Im thinking of getting the flanges cut on a cnc, they will be atleast 10mm, maybe more. And the cone thing im either going to beat out of a pipe or cut out of flat plate and beat that in to submission. How thick should the walls be though?
The current lenght was dictated by the wastegate actuator, which wont be there because i need to rotate the core for the oil drain, so i can probably go shorter by 2 or 3cm. The main issue with the adapters you posted is that i have to go from a square-ish hole to an oval.

 

[Nz Nath]

I don't think the length would make a noticeable difference. Look how long the flow path from head to turbo is on equal length runners manifolds.


For the flanges, I'd use 12mm both for resistance to warping but also to allow for more taper in the hole.

In other words your manifold flange I would make with a round hole, then mark out the square on the manifold side, and start die grinding in the transition. You wouldn't have to keep a fully round hole on the turbo side of this flange, but by not making it the full square you'll have a much easier time for the bit inbetween the two flanges. For that bit I'd use some 40nb pipe, and slot the ends with a 1mm cutting disc. The turbo end you need to close up the diameter by only 4mm. Probably be a lot lazier to get that just by tapering the hole in the flange. The manifold end you need to open it up by 13mm which is quite a bit, but you could probably get half of that by tapering the flange hole without having a too steep transition.

 

[Nz Nath]

Also the obvious one for flange thickness that I forgot to mention, 12mm gives you more meat for filing it flat at the mating surfaces once you've finished welding. Because the outer edges of the flange will pull up towards the side you're welding. Even if you tack the flange down to something else stronger when welding, it'll probably still distort a little when you cut it free.

 

[Fantastika]

With the help of wood i have figured out how the final adapter should look. I also only just realised its a VNT turbo, so ill have to make some sort of device to control the VNT

 

[Fantastika]

Printed the adapter mk2, the turbo is sitting beautifully. Now just have to make it from metal

 

[RyanMiller]

I built a janky turbo set up on my Isuzu 1.8l where I cut the stock exhaust and put a 90 to send it back up to the turbo.. almost 2ft of up pipe. it still builds boosts quick. I also have seen many set ups with the turbo in the trunk. needless to say, Its not something to really worry about unless you are going for competition performance.

 

[Fantastika]

I built a janky turbo set up on my Isuzu 1.8l where I cut the stock exhaust and put a 90 to send it back up to the turbo.. almost 2ft of up pipe. it still builds boosts quick. I also have seen many set ups with the turbo in the trunk. needless to say, Its not something to really worry about unless you are going for competition performance.

Thats good to know, but considering ive gotten the adapter lenght down to 50mm i think im gonna be just as good as if i had welded a new manifold. Also nice truck, love seeing the setups that are more down to earth.

 

[Dusten]

Each cylinder is pushing .7L of air every 2 full revolutions.
At idle that's 4.7L per second per cylinder.
Or 28L total.

So an adapter would need to have a volume or 28L to increase spool time by 1 second.

If that round adapter is in mm and 36mm then it would need to be 2800cm tall to increase lag by 1 secone