35 replies to this topic

[nafnaforiginal12]

I've had a quick look through threads but i didnt see any that went into the actual pro's and cons of turbo or supercharging in comparison with eachother.

Just wanted to know about power potential, reliability, installation difficulty and costs and which turbo's are best. etc etc.

[Wil_h]

Supercharger:
Advantage - low boost threshold
Disadvantage - Limited power (for charged engine), poor fuel consumption, high intake temps, fixed boost

Turbo
Advantage - More power than you need, variable boost, good mpg
Disadvantages - the temptation to up the boost

As for reliability, both are the same and cost is similar. There are cheap SC kits out there, but you get what you pay for. If you compare a suck through SC compared to a blow through turbo, the turbo is a more complicated build. But the results are better.

I'm biased of coures, but that's only because I made the right engineering decision!

[imvarma]

Just to expand on the OPs question, what Turbo/ SC kits are there about and which are the best quality for a sensible price?

[Wil_h]

There are no turbo kits other than using all the Metro turbo stuff.

[Beej123]

There is also a lot more help out there for the turbo stuff, not so much with the SC so if you are new to it, the help you can get might sway your decision!

[nafnaforiginal12]

yeah,going turbo is certainly sounding better than supercharging.

Anyone know much about the performance differences between:
T3
T2
T2.5
GT1752(I think thats the right number)

I know that you have to mod the bulkhead to fit the T3 so i wouldnt want to do that.
I like the look of the mirage manifolds but theyre single downpipe unlike the LCB, does this have performance effects?

[mini93]

Ill turbo's have single down pipe after the turbo... post turbo the exhaust gasses can do what ever they like, they have used their useful power to turn the turbine... if it were neccesary on application you dont even need a pipe after the turbo as the turbo also acts as a sort of silencer

[Beej123]

What size engine are you looking at charging?

[Wil_h]

The normal rule is "first chose your power class, then choose your guns"

i.e. what power are you aiming for? once you know this you can choose the right turbo.

[nafnaforiginal12]

I'm thinking 1380cc offset bore,
MED FIS head,
either SC typhoon ecu or emerald k6 ecu for engine management,
ultralight flywheel,
lightened, balanced and wedged crank?,

any more suggestions on a spec?
It will be a road car but i'd like big power.

[crock]

If you want big power, the turbo chooses itself. Once you go over 10 psi boost, the supercharger requires an intercooler which is more difficult to plumb in than for a turbocharger. A supercharger works best for somebody who would like the 1275 to behave like a 2.0 liter engine (sounds good to me!). The advantage of a supercharger is that it is relatively easy to map the fuel injection. You could probably get it done reasonably well in a single rolling road session. A turbocharger, especially at high boost, is very difficult to map. In fact, if you decide to go with a turbocharger, spend a lot of effort trying to find somebody who has a fully sorted installation and then copy what they have. I cannot over emphasize that it is very difficult to map the injection/ignition of a high boost (12+ psi) turbo. You will likely go through an engine before you get it set correctly.

Just to illustrate the difficulties ahead, with a supercharged engine the fuel demand for a given rpm and throttle position is always the same. The fuel demand for a turbo at any given rpm and throttle position depends on the boost the turbo is delivering that moment. The air/fuel ratio for a turbo needs to change with the boost level to get best performance and low throttle lag, so the mapping is considerably more difficult. When setting up a supercharged car, I could get the fuel injection working reasonably well in about two hours on a rolling road. A custom turbocharged application takes 7-8 hours of rolling road and several days of driving around and fiddling to get right. If you talk to anybody who is actually driving a turbo mini with 12+ psi boost, I am sure they will tell you that they are still working on getting their EFI mapping just right.

[nafnaforiginal12]

oh right, didnt realise how difficult it was to map for a turbo.

[Turbo Phil]

Out of interest why 1380 & why the flash ECU ? Are you actually planning on injecting it or just running a carb ? The simplest & cheapest install will be a single carb & something like Megajolt.

Phil.

[Liam Mini 35]

Have you had a look at turbominis.co.uk and turbomini.com? Have a look there and a good read of the info, lots on those wsbsites. Have you also loole in the yellow bible? But go turbo, thats what i decided to do after discussing it on the above sites. Loads more power )

[nafnaforiginal12]

Out of interest why 1380 & why the flash ECU ? Are you actually planning on injecting it or just running a carb ? The simplest & cheapest install will be a single carb & something like Megajolt.

Phil.

Because it's an spi so the typhoon ecu would just plug in. and 1380, i just thought it would have more power. am i wrong?