10 HP/lb of boost?

[summit889]

The GT28 will make more HP at the same output boost level, as it is a larger pump, putting more lbs/hour of air into the motor.

That's the way I have always understood it.

 

[Rucky]

That's the way I have always understood it.

What he's saying is that 12 PSI is twelve PSI no matter what sort of pump is making it happen. In a way you're both right depending where the boost is measured in the system and how big the plumbing is really. If you have 12 PSI in a 1 inch tube, and 12 PSI in a 2 inch tube, the 2 inch one contains more air obviously.

 

[summit889]

What he's saying is that 12 PSI is twelve PSI no matter what sort of pump is making it happen. In a way you're both right depending where the boost is measured in the system and how big the plumbing is really. If you have 12 PSI in a 1 inch tube, and 12 PSI in a 2 inch tube, the 2 inch one contains more air obviously.

That's fine. What I was saying is a bigger turbo moves more air and produces more hp/ lb of boost

 

[overkill131313]

but an engine can only take in so much air....that is why you have to turn up the boost. more boost , more power. we cant change the tube diameter from a 1 inch to a 2 inch (using that as a example) so 12 psi is 12 psi no mater what turbo is on it.....but when the little turbo has moved all the air it can, and runs out of push then a bigger one will keep building PSI and make more power.

but I only have a grade 6 education and know nothing....so dont jump on me if im wrong lol!

 

[Longhairfreak]

but an engine can only take in so much air....that is why you have to turn up the boost. more boost , more power. we cant change the tube diameter from a 1 inch to a 2 inch (using that as a example) so 12 psi is 12 psi no mater what turbo is on it.....but when the little turbo has moved all the air it can, and runs out of push then a bigger one will keep building PSI and make more power.

but I only have a grade 6 education and know nothing....so dont jump on me if im wrong lol!

One thing I do know is lb for lb of boost any 2 stroke ove 800cc will spank a Yamaha. Any one care to correct me?

 

[tapex]

One thing I do know is lb for lb of boost any 2 stroke ove 800cc will spank a Yamaha. Any one care to correct me?

Let the show begin! ALREADY!!!

 

[TABSTER]

One thing I do know is lb for lb of boost any 2 stroke ove 800cc will spank a Yamaha. Any one care to correct me?

i was going to add a coment to this and then i realized........ why waste you time.

Getting tired of all the Keyboard riding..........Bring on the Snow!

 

[shawnmcgr]

That's fine. What I was saying is a bigger turbo moves more air and produces more hp/ lb of boost

The lbs/sec of air that goes through the motor is fixed by the air density at the throttle body inlet (kg/cc), the motor displacement and rpm (which give you cc/s). So if the air density at the throttle body does not change (temp and psi) then hp will not change. Like OK said, this is why we turn up boost. You cannot change the cc/s a motor will sweep, unless you are going to make physical changes like valving, etc.

So ya, I guess I was saying air density is air density whether it supplied by a turbo, supercharger, or bat wings.

If you mean more volume @ standard temp. & pres. then we're on the same page. I don't think everyone gets that difference. It's confusing as the kgs of air in any volume depends on the temp, pressure, relative humidity. I think of it as mass, a larger turbo will move more more mass (kgs) of air (thanks Pistonbroke). And the only way a larger turbo can do that, without increasing boost, is to provide that air at a lower temp.

Garret has a good site with more detail than you want to know:

http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech101.html

 

[summit889]

One thing I do know is lb for lb of boost any 2 stroke ove 800cc will spank a Yamaha. Any one care to correct me?

I know a 1000 will, not sure on the 8's. Don't see many 800's running 18-20 lbs boost. I'd be curious to see an m8 run all season at 18lbs on pump gas and what the maintenence costs would be. For me last year it was one belt and 2 liters of oil.

 

[Longhairfreak]

I know a 1000 will, not sure on the 8's. Don't see many 800's running 18-20 lbs boost. I'd be curious to see an m8 run all season at 18lbs on pump gas and what the maintenence costs would be. For me last year it was one belt and 2 liters of oil.

Something tells me an 800 on 12-13 lbs would give a Yamaha on 18-20 lbs a fit.

 

[summit889]

Something tells me an 800 on 12-13 lbs would give a Yamaha on 18-20 lbs a fit.

I don't think 12-13 is enough, but I could be wrong. Didn't buy it to be the fastest. Wanted something with some power that was reliable.

 

[overkill131313]

5000 plus miles on a boosted engine! (dont need a new engine every year) that is what I wanted! plus mine is a work sled not a "look at me sled"

 

[glengine]

At the spectro oils booth at the sled show in edmonton they will have one of the pistons out of Crazy Canadian's Turbo M8 and they have 4000miles on them and still look good.

 

[TABSTER]

I ride what I hand built........It gives me great pleasure and Hard wood!