998 Ti - Stage 2 - Now the Build - Jan 2012
Turbo Mini Forums

What do you reckon? Worth drawing in 3D and doing a CFD run?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

It's a slightly smoother path for the air and a bigger area at the entry, but guess you won't be able to use a ram pipe at entry though.

Engine is looking good :)

I'm mainly concerned about swirl in the runners caused by the tangential entry.

Otherwise it ticks all the boxes, 300mm runner length and it moves the plenum forward so that the throttle body is not where the master cylinders sit.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Oh, and the arrangement is generally going to be like my avatar to the left <<<<

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

what would happen if you moved the plenum forward and had a full 180 bend in the runner and slightly longer? air wouldn't enter on a tangent then.

one day boost will be mine!

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Got on well with the exhaust manifold:



So got youngun to CAD up the inlet in Solidworks for a spot of CFD:





Flow paths look fine to me :)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Looking good - doesn't seem to be any problems with swirl in the runners. I was going to ask if you purged the manifold, but can see how you have done this with the cylinder head now!

Are you going to have this ready for any shows this year or is the miglia coming out for that?

There's no swirl. The tangential exit from the plenum does send the flow to the outside of the runner but that tends to happen in bends anyway. It's straight and reasonably well distributed at the head flange.

I always back purge. I've got thick steel flanges with tappings to connect the hose. The flanges also prevent distortion when welding on the head and turbo flanges. Just a bit of welding gas to exclude the oxygen in the air. The weld inside the pipes is then nice and smooth.

Doubt if this will be ready this year as I have to paint the car first, as well as all the other projects.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Paul, i would buy one of your manifolds if you ever decide to do a run of them that is beautiful 1000 times neater than what i could muster,

i had to look twice at that turbo too, was thinking what the fff?... then realised its the gearbox

Yes i moved to the darkside

Instagram @jdm_brett

Thanks Brett.

Trouble is that they are a pain to make. Everything fits and lines up when it's all tacked together. Start doing the final welds and it starts moving all over the place. I had to cut and re-do at least 4 of the joints :(

Having said that, I'm working on the next evolution of the design and hopefully that will be easier to make.

Trial fit on 'ngin:

Edited by Paul S on 10th May, 2012.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

hopefully this year i will make a start, but its hard to change something that works i just want to enjoy it at the minute

Yes i moved to the darkside

Instagram @jdm_brett

Wow Paul the engineering in this is amazing and so detailed :) was nice to see it in the metal too. Keep up the good work.

Thanks Stephen.

This reminds me that I need to do an update on the inlet manifold as it is all changed. Now billett CNC bosses and an alloy plenum with even longer runners.

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=480014

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

After 18 months of just sitting on my bench, I thought that I better get this finished:





Everything optimised for peak torque at 6000rpm on 0.8 bar boost. Rev limit 8000rpm. Should net 120 lbft. Built for inevitable future boost increase and 170 lbft :)

Now where did I put that car to put it in?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

looking good. Is that a sensor on the final drive for wheel speed?

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

Looks like it. Brett did something similar.

If something is worth doing, it's worth doing half of.

looking good, wasnt bretts for traction control

What the mind can conceive the mini can achieve
MITP 2012 17.01 seconds 1/4 mile against "The Don"
MITP 2013 16.83 seconds 1/4 mile

Same thing

If something is worth doing, it's worth doing half of.

be interested in that for my build

On 21st Oct, 2013 John said:
Same thing

What the mind can conceive the mini can achieve
MITP 2012 17.01 seconds 1/4 mile against "The Don"
MITP 2013 16.83 seconds 1/4 mile

It's a hall sensor picking up wheel speed from the crown wheel.

As well as giving vehicle speed, it can be used for traction control and gear based boost control.

Easy direct connection of the signal wire into the ECU, the rest is done in software.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."