Im looking a purchasing my friends SC61 setup. Full spool at 5500rpm on an 84mm sleeved block pushing 20-25lbs.
If im ls/vtec running 81.5mm bore 10psi.....Will the full spool still be 5500 or will it be lower. Thanks

 

You're displacement is less than his, so in theory it will take you more RPM before you get full spool.

 

Yea im still trying to learn in the turbo field. So even if its considerably less psi and it will still be longer into the rpm before i get full spool?

 

The stroke is just as important as the bore in affecting "spool". Either way, you're still going to be in the 4700-5500rpms to reach maximum pressure on a sub 2.5 litre engine. It is a turbo made for top end power, that's all there is to it.

 

Im just trying to figure out weather to put the SC61 setup on the ls until my other lsv motor is done. but if i will only have <2krpm use of full spool use i dont know if its even worth it and just wait till i can take it higher into the rpm and put it on that build.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan &raquo;</TD></TR><TR><TD CLASS="quote"> It is a turbo made for top end power, that's all there is to it.</TD></TR></TABLE>

I see what your saying, but in theory wouldn't this turbo be best placed on a B16 due to the fact that they make most of their power up top and in combination they would work great? Or am I wrong on this and its best on a B18 because it spools a little quicker?

 

It was on a motor being taken to 10k but only for about 10 passes.
It was on an EM1 but it was fully built and had a scat ls crank so the top end wasnt there that could have been.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97_coupe &raquo;</TD></TR><TR><TD CLASS="quote">

I see what your saying, but in theory wouldn't this turbo be best placed on a B16 due to the fact that they make most of their power up top and in combination they would work great? Or am I wrong on this and its best on a B18 because it spools a little quicker?</TD></TR></TABLE>

Sometimes logical hypothetical thinking and actual physics don't match up. You have to look at this from an exhaust energy standpoint (fluid dynamics). The exhaust flow of the B16 is best at higher rpms where the larger turbo would be a bit more efficient, but below that crucial moment of inertia (say, before 6000rpms) it takes more time to get the exhaust energy to a velocity that would suit such a large turbo. That duration of time between the low end of exhaust energy and maximum pressure is "lag."

Your theory would work if you kept the exhaust velocity high ALL THE TIME (meaning above 6000rpms) but since most street users don't do this, it would not be practical. that's why you have to find the turbo that is a balance b/w overall power and transient response in-between gears during driving.


Modified by TheShodan at 2:49 PM 9/18/2008

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92VXeg &raquo;</TD></TR><TR><TD CLASS="quote">It was on a motor being taken to 10k but only for about 10 passes.
It was on an EM1 but it was fully built and had a scat ls crank so the top end wasnt there that could have been.</TD></TR></TABLE>

Just because it doesn't rev to kingdom come doesn't mean that it doesn't have top end power. This is because with the increase in your stroke, your torque/weight ratio just went up a notch or 2.

i.e. a 2.2 litre AP2 S2000 revving to 9000 rpms, has the same piston speeds as a 2.0 litre AP1 S2000 revving to 10,000rpms.

 

wow i feel like i actually learned something today. thanks TheShodan..../end nut swing

My power goals are around 400 DD.
84mm (2.0?)
Ls crank.
Is an SC61 setup a good way to go for my goal or should i go with something that would smaller that would spool quicker. I dont want to have to wait till 6k to feel the power.
Ive been doing as much research as possible with what i know and this is my first boost project. Ive seen some really bad turbo lag vids and i dont want that at all.
thanks for the info

 

An SC61 can work with a 84mm X 89mm combination, (at least it can suit it a bit better), But I'd look at a Silver Surfer 60-1 or Borg-Warner S258 to make that good "fun" factor with that displacement as opposed to an SC61

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92VXeg &raquo;</TD></TR><TR><TD CLASS="quote">It was on a motor being taken to 10k but only for about 10 passes.
It was on an EM1 but it was fully built and had a scat ls crank so the top end wasnt there that could have been.</TD></TR></TABLE>


Your all wrong about his set up. The scat crank has never been down the track at all. You will see it friday. He has been running on a stock Ls crank and a set of eagle rods. The eagle crank it started with snapped the flywheel snout off. The scat crank is in there because he stretched all the eagle rods. He is now running manly rods and scat crank.

 

oooooooo so all the stuff that he has now hasnt been in the car? well all the better. I'm hearing more and more about this silver surfer set up..

forced00si....will you see what you can get? And what are tuning equiptment are you running. ive been meaning to ask you.. .And why is he putting that much more money in it when he has had plans to sell it.

My bad james on the wrong setup...i just stated what i thought what it was without knowing he changed it. i knew he fixed it but didnt know it had as much difference as it does.


Modified by 92VXeg at 12:46 AM 9/19/2008

 

Modified by 92VXeg at 12:46 AM 9/19/2008[/QUOTE<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92VXeg &raquo;</TD></TR><TR><TD CLASS="quote">oooooooo so all the stuff that he has now hasnt been in the car? well all the better. I'm hearing more and more about this silver surfer set up..

forced00si....will you see what you can get? And what are tuning equiptment are you running. ive been meaning to ask you.. .And why is he putting that much more money in it when he has had plans to sell it.

My bad james on the wrong setup...i just stated what i thought what it was without knowing he changed it. i knew he fixed it but didnt know it had as much difference as it does.


Modified by 92VXeg at 12:46 AM 9/19/2008</TD></TR></TABLE>

in order: I am not running at the track yet
Hondata s200
he wants to drive it the rest of the season. and it is for sale as a whole. hard to sell a broken whole.
its ok you didn;t know