214 HP and rising.

**bugjuice** · 27th January 2006, 14:27

http://cgi.ebay.com/ebaymotors/Suzuk...QQcmdZViewItem

**cowpoos** · 27th January 2006, 14:59

Originally Posted by Lou Girardin

At full throttle a naturally aspirated engine still has a slight vacuum.
In contrast, a forced induction engine has a positive pressure in the intake, in this case 6 psi. Or nearly half as much again as N/A
In effect this increases the capacity of the engine, which is why motorsport has a multiplier formula to maintain parity with N/A engines.
In F1 it was reckoned that a turbo'ed 1.5 litre was equivalent to 3 litres N/A.
Which we all know was bullshit, it was more like 9 litres.

not quite correct...and naturally aspirated engine will always run a vacuum...and so will a forced induction engine in many cases...depends on how well the inlet and outlet flow air...just because a turbo is making 10psi at the manafold it doesn't mean its makin that at the valve...and besides psi is still very missleading...it should be cfpm as your engine is a air pump...the more air your engine flows at any given point in the rev range the more tourqe it will produce and multiplied by rpm will give you hp...

motorsport uses restricers alot rather than using equivelent asumptions now days...as the restricters....restricted cfpm...

**Marmoot** · 27th January 2006, 15:04

Originally Posted by cowpoos

not quite correct...and naturally aspirated engine will always run a vacuum...and so will a forced induction engine in many cases...depends on how well the inlet and outlet flow air...just because a turbo is making 10psi at the manafold it doesn't mean its makin that at the valve...and besides psi is still very missleading...it should be cfpm as your engine is a air pump...the more air your engine flows at any given point in the rev range the more tourqe it will produce and multiplied by rpm will give you hp...

*bump*

....
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........from now on I think I'll just stick to porn

**ducatilover** · 27th January 2006, 15:04

my dads fj is loosing vacum... :slap:

**cowpoos** · 27th January 2006, 15:05

Originally Posted by WINJA

GIVEN THAT THE ATMOSPHERE WE ARE IN RIGHT NOW (IM AT SEA LEVEL) IS ABOUT 14.7 PSI ABS OR 0 GAUGE WE THEN SAY THAT AT 14.7ABS PSI OR 29.4 PSI GAUGE YOUVE EFFECTIVELY DOUBLED THE CAPACITY OF THE ENGINE , THIS IS CALCULATED WITH NO PREASURE DROP FROM ATMOSPHERE TO COMBUSTION CHAMBER BUT ITS BALL PARK .
HOPE ITS GOT A SHOW OFF VALVE FITTED PISHHHHH PISHHHHHHHH

but a N/A engine doesn't run a positive pressure at all......not even close to 14.7psi or 1 bar [which is atmospheric presure] and a forced induction engine would be havin to run bloody high manifold pressure to even get 14.7 psi at the valves...

**cowpoos** · 27th January 2006, 15:10

Originally Posted by Marmoot

As winja said.

As a rule of thumb, assuming 100% efficiency (i.e, ideal situation), for every 1 bar (= 16psi? not sure what the exchange rate is between psi and bar) of forced induction roughly equals to doubling the engine capacity.

Also, Spec-sheet compression ratio figures are compiled based on the volume of combustion chamber when piston is down against the volume of the chamber when piston is up. However, to see how forced-induction can affect the engine performance you will need to see the compression ratio from a different angle. If you compare the volume AND density of air (mixed with fuel) between piston-down and piston-up, it will not be the same figure anymore.
The volumes of those two situations may still be the same. But, the pressure (now twice the pressure from original engine) is now doubled and therefore I can say that compression-ratio for this engine has doubled. For example, what originally was 11:1 now has become 22:1. Yes, psi/bar figure relates to horsepower like steak to a horse.....if you like horse steak. And they actually do Horse steak in Asian countries where cows are expensive.
Disclaimer: this is only my way of explaining how denser air relates to higher horsepower, and is in no way an official way of explaining compression ratio. So you will not see any 22:1 compression ratio out there on any working bike engine.

Given that there will be engineering compromises (ignition retarding, lower compression, etc) and non-ideal situations (frictions, engine inefficiency, etc) then you might be looking at 60-75 percent increase instead of 100 percent.

So, at 18psi you can make the 1k will be quite like GSXR2100.
But, the power will not be 2.1 times the original.

That is if the engine does not blow up first. Those water jacket rupture can kill pistons very quickly.

If it is me, I wouldn't worry about the power so much. I would definitely get the Pishhh valve first! Turbo is all about fashion statement.

I had a supercharged toyota levin about 8yrs ago...it had the factory boost set at 8psi...when we modified it we replaced the supercharger altogether with a sprintex...and we ran 5psi... after a few fuelinjection tweaks [link computer replacment] it ran 243 hp at the front wheels...standard it was running 141hp.... gained over 100hp with less boost... more volume of air was the key...

**Momentum** · 27th January 2006, 15:17

all this talk about turbos makes me want one

**WINJA** · 27th January 2006, 15:31

Originally Posted by cowpoos

but a N/A engine doesn't run a positive pressure at all......not even close to 14.7psi or 1 bar [which is atmospheric presure] and a forced induction engine would be havin to run bloody high manifold pressure to even get 14.7 psi at the valves...

YOU SHOULD AWAYS CONSIDER A VACUM TO BE NON EXISTENT IN THESE SITUATIONS , WE ARE AFTER ALL SITTING IN 1 ATMOSPHER OR 101KPA OR 1 BAR OR 14.7PSI ABS (NOT GAUGE).
DID YOU NOTE I SAID IT WAS BALLPARK AND IT DID NOT INCLUDE PREASURE DROP.
SO BEFORE YOU HIT THE STARTER WOULD IT BE FAIR TO SAY AT LEAST ONE CYLINDER WOULD HAVE 14.7PSI ABS INSIDE? AND WOULD THAT BE THE CASE WITH THE THROTTLE FULLY OPEN AT CRANKSPEED ? WHAT ABOUT FLAT OUT IN TOP WITH THE THROTTLE WIDE OPEN THEN AT BDC WITH THE INLET CLOSED AND THE EXHAUST VALVE SHUT WHAT WOULD THE PREASURE IN THE CYLINDER BE BEFORE THE UPSTROKE ???

**bugjuice** · 27th January 2006, 15:32

i remember seeing a website of some guys who added fuel injection to a CBR250RR and then added a turbo. I've been searching for it for ages, and can't find it.

But anything can be turbo'd

**Momentum** · 27th January 2006, 15:35

that would be one fast little 250
if you can find the link pm it to me.
is it harder to turbo a carb over injected?

**bugjuice** · 27th January 2006, 15:41

if I find it, I'll post it, cos it's a good read. It explains all the issues they had, and how they overcame them. And various things like the inlet manifold went thru 2 or 3 revisions to improve on. And how they built the injection rail etc

To turbo a carb vs inj, I personally wouldn't know. The easier would be the injection I would have thought, cos you just remap the computer and let it figure out the rest, where as carbs have to be fiddled with to find the right mixture. Both can be done, it's just one is easier than the other.

**Lou Girardin** · 27th January 2006, 16:28

Originally Posted by cowpoos

not quite correct...and naturally aspirated engine will always run a vacuum...and so will a forced induction engine in many cases...depends on how well the inlet and outlet flow air...just because a turbo is making 10psi at the manafold it doesn't mean its makin that at the valve...and besides psi is still very missleading...it should be cfpm as your engine is a air pump...the more air your engine flows at any given point in the rev range the more tourqe it will produce and multiplied by rpm will give you hp...

motorsport uses restricers alot rather than using equivelent asumptions now days...as the restricters....restricted cfpm...

Sorry but rubbish. I built a supercharged MX 5 engine, at full boost/full throttle it had 7.5 psi at the manifold, at the end of which are the valves. The whole induction system from the throttle body is pressurised.
At less than full throttle it did run a vacuum, that's what forced induction engines do.

**Lou Girardin** · 28th January 2006, 10:40

I've just had a close look at the Gixxer. It's one of the tidiest installations I've seen, fabrications look like factory items, the guy is very clever. You can't tell it's non-standard except for a cut-out in the fairing to clear the header and if you look closely you can see the turbo in the front fairing opening.
He says it goes just like a standard bike only with much more grunt.

**crash harry** · 28th January 2006, 11:55

I suppose a lot of people have already seen this but hey...
Muzzys do a kit for the ZX-10R which supposedly gives around 250hp at 5psi. Now being advertising material I expect that to be absolute best case, so 214 at 6psi in an older gixxer sounds easy peasy...

Of course the graph at 28psi is more impressive... I wonder what fuel they're running it on? The kit doesn't seem to include any kind of decompression...

http://www.muzzys.com/ZX10/ZX10_Turbo/index.html