I'm back and going cogged!
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Update(or lack of update).... I'm still waiting on the damper from ATI. I called last week and they said they were shipping it off to be plated. This thing better look like a million bucks when I get it!
The prior owner of my ysi was seeing 17lbs off boost out of the serpentine. The shop (Nelson Racing) said it was still slipping a little. The most boost I've seen regularly is 11psi and 14 psi on one occassion. I predict at least 15psi out of my 74 tooth/27tooth blower combo. I just hope the belt will hold together. This should be enough power to get me my 9.XXX timeslip.
I have the idler pulley installed as well as the blower pulley. I'm just waiting on the crank pulley.
On a different note, there's a nice straightaway next to my condo about a 1/2 mile long (at least a full quarter of a mile) with no sidestreets what so ever. It's on the edge of Irvine, so on the weekends its a ghost town. I have another awesome test track!
The prior owner of my ysi was seeing 17lbs off boost out of the serpentine. The shop (Nelson Racing) said it was still slipping a little. The most boost I've seen regularly is 11psi and 14 psi on one occassion. I predict at least 15psi out of my 74 tooth/27tooth blower combo. I just hope the belt will hold together. This should be enough power to get me my 9.XXX timeslip.
I have the idler pulley installed as well as the blower pulley. I'm just waiting on the crank pulley.
On a different note, there's a nice straightaway next to my condo about a 1/2 mile long (at least a full quarter of a mile) with no sidestreets what so ever. It's on the edge of Irvine, so on the weekends its a ghost town. I have another awesome test track!
Team Owner
Joined: Mar 2001
Posts: 30,846
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
OK
ran these #'s, figuring about ~100hp to run the blower
torque = (HP*5252)/RPM
100hp
7,000 engine rpm
75 ft*lb @ crank
74 tooth/27tooth
~20,000 rpm @ blower
~26 ft*lbs @ blower
So that's tells us roughly the sized sprag we need.
ran these #'s, figuring about ~100hp to run the blower
torque = (HP*5252)/RPM
100hp
7,000 engine rpm
75 ft*lb @ crank
74 tooth/27tooth
~20,000 rpm @ blower
~26 ft*lbs @ blower
So that's tells us roughly the sized sprag we need.
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
If the YSI is anywhere close to the D1R, you should see considerably more boost than that from your combo. As boost is the measure of resistance to move air, I would bet that you have smaller heads, smaller cam, less cubes, and a more restrictive intake, so you would expect more boost if you are spinning to max flow (MIS). The D1R with the revised impellor produces 2300CFM at MIS, so you should see more than the 26+ that I see.
I ran the cog for quite some time with the IC, but only saw 18 psi (only 14.5 psi on cold winter nights and 11.5 psi normally with the serp, so ~3.5 - 6.5 psi gain from serp to cog). I do not see much dust, so I can't be slipping much with the current serp routing. It would be interesting to re-install the cog and see if the boost stays the same.
Kind of pointless, but interesting nonetheless.
Aaron
I ran the cog for quite some time with the IC, but only saw 18 psi (only 14.5 psi on cold winter nights and 11.5 psi normally with the serp, so ~3.5 - 6.5 psi gain from serp to cog). I do not see much dust, so I can't be slipping much with the current serp routing. It would be interesting to re-install the cog and see if the boost stays the same.
Kind of pointless, but interesting nonetheless.
Aaron
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Aaron
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Aaron,
I believe that the ysi step up is 3.45 to 1. It flows right around the same amount as the d1r. I like to think of it as flowing slightly more than the d1r but less than the f1r. The only thing is that I'm not going to be spinning the blower that hard so I definately won't be seeing all of the air flow it's capable of. I'll probably be shifting at about 6000 until I get a new cam and better valvetrain.
I believe that the ysi step up is 3.45 to 1. It flows right around the same amount as the d1r. I like to think of it as flowing slightly more than the d1r but less than the f1r. The only thing is that I'm not going to be spinning the blower that hard so I definately won't be seeing all of the air flow it's capable of. I'll probably be shifting at about 6000 until I get a new cam and better valvetrain.
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Aaron,
I believe that the ysi step up is 3.45 to 1. It flows right around the same amount as the d1r. I like to think of it as flowing slightly more than the d1r but less than the f1r. The only thing is that I'm not going to be spinning the blower that hard so I definately won't be seeing all of the air flow it's capable of. I'll probably be shifting at about 6000 until I get a new cam and better valvetrain.
I believe that the ysi step up is 3.45 to 1. It flows right around the same amount as the d1r. I like to think of it as flowing slightly more than the d1r but less than the f1r. The only thing is that I'm not going to be spinning the blower that hard so I definately won't be seeing all of the air flow it's capable of. I'll probably be shifting at about 6000 until I get a new cam and better valvetrain.
Why would you not want to spin the unit to max impellor speed, as you have been trying to get higher boost? What is the max impellor speed of the YSI? You will be spinning to ~57K at 6,000 engine RPM.
Aaron
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
I don't think I'll be able to get the belt to survive with as small of a pulley as it'd require to spin it close to the top impeller rpm. I'd probably need at least a 24 or 25 tooth if not smaller. The top end of the ysi is 65,000 rpm. Without a bigger crank and with my low rpm ceiling, I don't have too many options.
Also, my goals are relatively modest. I'm just trying to break 700 rwhp on pump gas and get into the high, high 9's at the track. I think if I pushed things anymore, it'd be a bomb waiting to go off.
I'm hoping for 15psi+ of boost out of this setup, but I realistically have a feeling that it'll bury the 20lb guage. I just don't want to expect too much because I'm hoping that this is the last mod for a while to the car other than rebuilding the trans.
Also, my goals are relatively modest. I'm just trying to break 700 rwhp on pump gas and get into the high, high 9's at the track. I think if I pushed things anymore, it'd be a bomb waiting to go off.
I'm hoping for 15psi+ of boost out of this setup, but I realistically have a feeling that it'll bury the 20lb guage. I just don't want to expect too much because I'm hoping that this is the last mod for a while to the car other than rebuilding the trans.
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
...Also, my goals are relatively modest. I'm just trying to break 700 rwhp on pump gas and get into the high, high 9's at the track. I think if I pushed things anymore, it'd be a bomb waiting to go off.
I'm hoping for 15psi+ of boost out of this setup, but I realistically have a feeling that it'll bury the 20lb guage. I just don't want to expect too much because I'm hoping that this is the last mod for a while to the car other than rebuilding the trans.
I'm hoping for 15psi+ of boost out of this setup, but I realistically have a feeling that it'll bury the 20lb guage. I just don't want to expect too much because I'm hoping that this is the last mod for a while to the car other than rebuilding the trans.
My biggest sin was the fact that I always had a lot of MPH. When I was running the D1, I was steadily running in the 141-143 range in the 1/4, which said I should have been able to deliver 9s easily (but never did on that combo with the D1). I found out that I had some drivetrain issues, and immediately went into the very high 9.8s. I played with that for a while and stayed in the 9.8-low 9.9 range but was back up to 144-145MPH. I later made some further changes (blower, cam, and intake and went high 9.7s but at 151 (some slower 60' times at 153+).
That was a big change!For the last 2 years I have worked on improving my short time, and that delivered nearly 0.5 secs (went from very unpredictable 1.95s to 2.85s 60' to a pretty steady low 1.7s to high 1.7s) and delivered my best ET of 9.34 at 153, and a slightly slower 9.38 at 154+.
It never stops, until you find another fix. Right now these bikes and job change seem to be my fix.
Good luck with your "modest" goals.
Aaron
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Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
haha! The one thing I have going for me now is that the car is an auto so I should be able to get some decent 60's to shave time off the front end which will pay dividends on the back end. I'm currently in the high 1.60's, low 1.70's leaving off the footbrake. I should be able to muster up some high 1.40's, low 1.50's once I get a new converter. I don't expect to trap as high as you so I'll need to get it moving good in the 1/8.
Hey, what have you replaced in your driveline to handle the power you're making? More specifically in the rear end...
Hey, what have you replaced in your driveline to handle the power you're making? More specifically in the rear end...
Team Owner
Joined: Mar 2001
Posts: 30,846
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
you could go to a two belt system.
engine > sprag > blower
That would make it easier to put a smaller pulley on the blower
The trouble with any of these setups is going to be the rotation mass.
Which is non-trivial
engine > sprag > blower
That would make it easier to put a smaller pulley on the blower
The trouble with any of these setups is going to be the rotation mass.
Which is non-trivial
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Yeah, I think this setup would definately benefit from a sprag. I just don't know when one will be available. If I could toss on a 25, I'll get some serious boost out of this thing!
Team Owner
Joined: Mar 2001
Posts: 30,846
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
What style are you looking for?
bearing style?
http://www.vxb.com/page/bearings/PROD/25mm/Kit8181
or cassette style?
http://www.formsprag.com/PDF/P-956-FC_pg014-047.pdf
(WARNING: large file) and rather large units as well!
bearing style?
http://www.vxb.com/page/bearings/PROD/25mm/Kit8181
or cassette style?
http://www.formsprag.com/PDF/P-956-FC_pg014-047.pdf
(WARNING: large file) and rather large units as well!
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
The cassette style have a diameter that is too large. The bearing style may work with approx 2 1/5" overall diameter. I'd probably run two of them. I'd love to work on a sprag project but I just don't have the time. I just bought a condo so hopefully someone else picks up on this project.
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
it's not completely custom, but it is a one off order. I had to pay an engineering fee to get it done ($250). I called once before and the price was over $1000. I don't know what the difference was this time, but I'll take it.
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
darn damper is a pain in the butt to get out. I struggled with it for about and hour yesterday only to not get it off. I'm going to have to totally undo the rack to get it out. I thought I'd be able to just loosen the rack, but I'm going to have to go to town n this bad boy.