Doodah

Was just idly wondering if I'll ever build that 2.0 ZVH in the back of my mind...carbed on a suck-through or blow-through (38 DGMS I reckon) I've never had a turbo before...

Why is the induction part always (I think?) right next to the exhaust part? Couldn't the rotational energy be transmuted up to the inlet with something like a very heavy duty speedo cable, then the charge fan would be right next to the inlet, wouldn't get hot so wouldn't need an intercooler & lag would be reduced to a minimum?

oldford

Probably because there's nothing that can withstand 100.000 (or more) rpm.

Doodah

Ah fair enough, thanks. How about a long shaft though, running in bearings, does anyone do that?

Fullflush

A turbo spins at more than 100,000rpm?

martysmartie

iTrader: (1)

It can do yes, as a matter of fact I think they are 'balanced' at that sort of speed.

The reason inter-cooling is required, is due to the fact air heats up when compressed.

Martin

jamie's

The idea behind it is to make it compact, if the 2 housings were split into 2 units then it makes it way more compicated, but it is possible and what your suggesting is bordering on modern formula 1 technolgy, they have the 2 housings seperate, but intercoolers are still req'd as the air will heat up when compressed as already mentioned

Doodah

Ach knew I was in the wrong job lol

Fairly clueless about all this but I thought most low-boost turbo systems don't have intercoolers or do they? Does the standard Fiesta or Escort RS turbo have one?

I'm thinking of keeping standard zetec pistons & bhp anything over the magic 100 per litre would do...am I being realistic I wonder


Ta for replies

martysmartie

iTrader: (1)

They do, but some don't, like older Diesel's for example.

Without some form of cooling then you will loose power, (especially with a high ambient temperature) as the IAT's will rise, so even with low boost it could still make a difference.

Martin

jamie's

Escorts and fiestas both had intercoolers from the factory,
Pretty much everything does these days,
Some older stuff didnt but they werent very efficient
They're fairly simple to fit so it makes sence to have 1,
If your going to the hassle of fitting a turbo then the extra work involved with fitting an intercooler is minimal, but very worthwhile

jontysafe

one of the 2015 F1 engines do exactly what you describe; decoupling the hot side from the cool side, possibly Mercedes. They then air-water chargecool because compressed air heats up.

William MK2 Cosworth

The old diesels, did not have an intercooler for a very simple reason:


The hotter the intake temperature, the better the fuel economy, but with very big power losses.

Hobomassiv

I wonder if you could sperate the two sides by having a shaft through the engine much like the driveshaft through the sump.

jamie's

Again, touching n modern formula 1 tech,
But it takes up a lot of space, and keeping the shaft lubricated is troublsome,
And balancing a longer shaft running thru other components at over 100,000rpm
Makes for even more trouble and expense,
But its possible, and formula 1 tech does quite often eventualy filter down to mainstream cars,
So very possible that it will happen in years to come