Ideal turbo specs?

[Grizzly]

Thanks, I have picked up allot from playing myself but it really helps learning the Basics first.

So when I felt power gains with when increasing the length was it an Illusion an basically all I was doing was moving the Torque band about?

Cheers

Chris

[bill shurvinton]

No you probably felt right. As you approach a length where there is beneficial exhaust scavenging you will increase the VE of the engine, which will help your power. A little longer and you will lose out until you hit the next resonant length for that RPM band.

But length per se does not add lag. the 3 or 4 revolutions needed to get a charge of gas from the chamber to the turbine is not noticable. the problem is heat loss if you do not have coated or wrapped manifolds which will mean less energy available to the turbine. Conversely lagging the manifold means excess heat to deal with at high RPM (hint: water injection works for this).

Where shorter manifolds can score is if you are completely optimising around the initial exhaust pulse and extracting maximum energy from that (S5 turbines used this principle, but the implementation let it down).

It\'s a complex system. Ideally you would rework the exhaust port to prevent divergence and then design the manifold to optimise the energy and flow for the power band you are after.

[wiggy]

I suppose this principle is the same on all turbo engines. I know from my old Cossies days people played around with manifold and turbo setups to optimise heat/energy getting to the turbine.

Is this more prominent of the rotary because of the increase in heat transmitted? I suspect it is and would assume a slightly longer length may aid this hense Chris\'s experience?

I was intending on lagging the pipes to keep heat in and would also be using the W/I system I have left over (somewhere) I guess it would be good to know for this situation just how much heat the bearings can handle in the turbo andit becomes more vital to use good quality oil changed regular to prevent it burning itself onto the inside of the oily bits.

I have recently been playing around with a friends GT4 and getting the Anti-lag working running of the DTA P8PRO, now, instead of an orange turbo he gets a more yellow/white glow. I\'ve warned him of the dangers (creamed turbo, zorst and manifold) but he seems happy to pay the price when it comes (very soon) I must admit, when I had it up and running on my old car it was bloody good fun not only can you drive like Colin McRea round the country roads you can now sound like him

So where do I get a custom length manifold made buy someone who knows what they are doing.....BILL....hint hint

[bill shurvinton]

I\'m not a fabricator. However if you contact Carl Hayward he should be able to help with where to get bespoke manifolds from.

Bill

[wiggy]

Carl Hayward as in Hayward and Scott???

Or is he not connected?

Any contact details? Is he on here?

Cheers

[20B_boy]

No, not as in Hayward and Scott!

Look at top of page for contact details, Hayward Rotary.

[Grizzly]

Manifolds are not to hard to make, just a tip though watch out for 1.2-1.5mm wall thickness ones. I have scraped the stainless one i had and now use mild steel (basicly steem pipe) i can get bends etc realy easily and it fusion welds well with the tig.

The only place i know that does Rx stuff is JP but its in the North west. May be worth a bell though You want Little rRick for manifolds and Big Rick For Exhausts.

http://www.jpexhausts.co.uk/index.html

Chris