HSR Dyno
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Ok, I finally got to the dyno last week and unfortunately, I did not hit the 400+ RWHP like I had hoped,, I've concluded that my cam is still too small for the HSR as it was for the Miniram, since my heads are 210 CC heads, I think I can move up to the ZZX Hyd Roller cam with a 239/239 duration or go to a solid roller in the 242/242 range.
No changes from 2004 to now except I had the heads cleaned up and had the valves back cut, whihc would explain the mild HP/TQ increase a the lower RPM ranges
Also, it looks like the size reduction of the HSR is a non issue up to 6000rpm
HSR October 2007 (Tune is good at WOT)
![](http://temp.corvetteforum.net/c4/ld85//dyno_hsr_oct_2007_sm.jpg)
Miniram Dyno from 2004 (car was rich & untuned)
No changes from 2004 to now except I had the heads cleaned up and had the valves back cut, whihc would explain the mild HP/TQ increase a the lower RPM ranges
Also, it looks like the size reduction of the HSR is a non issue up to 6000rpm
HSR October 2007 (Tune is good at WOT)
![](http://temp.corvetteforum.net/c4/ld85//dyno_hsr_oct_2007_sm.jpg)
Miniram Dyno from 2004 (car was rich & untuned)
![](http://temp.corvetteforum.net/c4/ld85//dyno_001.jpg)
Last edited by LD85; 10-07-2007 at 02:35 PM.
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Well, trying for max bragging rights has never been my goal, but I have learned a lot about cam sizing etc..
I received a lot of request for dyno info and I just haven't had time to get around too it until last week.
What is unique is that the HSR an MR yielded virtually identical #'s,, even with the plenum size reduction.
Knowing what I know now I would use a 239 or so cam if I stayed with a Hyd-roller cam,,, and I know that the bigger the cubes, the more cam the FI system can handle.
If I went with a Solid, probably a 242 or maybe up to a 246
I received a lot of request for dyno info and I just haven't had time to get around too it until last week.
What is unique is that the HSR an MR yielded virtually identical #'s,, even with the plenum size reduction.
Knowing what I know now I would use a 239 or so cam if I stayed with a Hyd-roller cam,,, and I know that the bigger the cubes, the more cam the FI system can handle.
If I went with a Solid, probably a 242 or maybe up to a 246
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I have a SR that is in the 248/254 @ 0.050", that replaced the old low 240 cam. I like the manners, and on a 408, it made peak TQ at just past 5500 RPM and was still climbing on the HP end at 6100 when the run ended.
Don't be afraid of a big SR.
Aaron
Don't be afraid of a big SR.
Aaron
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I bet the SR would bump you up closer to your goal, they "drive" a little smaller than they read on paper if thats what youre worried about. (as far as street manners go). IMO once you get to the high 230ish/low 240s its time to go solid roller, they just work better upstairs and rev very freely. Youll love it.
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Graph 1 is from a well-tuned HSR. Graph 2 is from a rich, untuned MR.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
#7
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Graph 1 is from a well-tuned HSR. Graph 2 is from a rich, untuned MR.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
I would have guessed that the Miniram, once fully tuned would have yielded @ 415RWHP or so, with the TQ still @ 405 RWTQ, this si clsoe to what ol'Rj got on his dyno with a near identical Miniram setup.
But the HSR probably took some peak HP away and yet the TQ was only slightly better.
Only thing I can think is that the cam was undersized for both intakes, due to the cubes and the AFR 210's, The runs were done on separate dynos, both being Dynojets.
When I look at Bjanski's dyno numbers I see better numbers but he used a TPIS ZZX cam @ 239/239.
Ths winter I might pull the cam and swap it out but I will probably go with a Solid Roller and be done with it.
I got one run at the drag strip last week and my accelerator bracket broke,,, 114mph,,, 2.2 sec 60' and 12.8 et, on a 90 degree day at 2:00pm. I'll go again with the bracket fixed when the weather is cooler.
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Graph 1 is from a well-tuned HSR. Graph 2 is from a rich, untuned MR.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
How can this be?
The two HP/TQ curves are essentially identical with little difference
that couldn't be attributable to equipment/climatic variation. My vote
is that there is something askew with the results as presented here.
Changing runner length from 3" (MR) to 6" (HSR) will change both the
shape of the output curves as well as their location relative to RPM.
As runner length increases, area under the TQ curve will increase as
TQ levels at lower RPM's rise. With enough increase in runner length,
peak TQ will begin to shift to a lower RPM.
.
John
#9
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Larry, let us know when you go back to the track. I'd like to join you. I think the Tuesday Night Drags at ORP end this month.
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Its the strangest thing I've ever seen, but the dynos speak for themselves. Two diff dynos run years apaert with bascially only an intake chaneg.
I would have guessed that the Miniram, once fully tuned would have yielded @ 415RWHP or so, with the TQ still @ 405 RWTQ, this si clsoe to what ol'Rj got on his dyno with a near identical Miniram setup.
But the HSR probably took some peak HP away and yet the TQ was only slightly better.
Only thing I can think is that the cam was undersized for both intakes, due to the cubes and the AFR 210's, The runs were done on separate dynos, both being Dynojets.
When I look at Bjanski's dyno numbers I see better numbers but he used a TPIS ZZX cam @ 239/239.
Ths winter I might pull the cam and swap it out but I will probably go with a Solid Roller and be done with it.
I got one run at the drag strip last week and my accelerator bracket broke,,, 114mph,,, 2.2 sec 60' and 12.8 et, on a 90 degree day at 2:00pm. I'll go again with the bracket fixed when the weather is cooler.
I would have guessed that the Miniram, once fully tuned would have yielded @ 415RWHP or so, with the TQ still @ 405 RWTQ, this si clsoe to what ol'Rj got on his dyno with a near identical Miniram setup.
But the HSR probably took some peak HP away and yet the TQ was only slightly better.
Only thing I can think is that the cam was undersized for both intakes, due to the cubes and the AFR 210's, The runs were done on separate dynos, both being Dynojets.
When I look at Bjanski's dyno numbers I see better numbers but he used a TPIS ZZX cam @ 239/239.
Ths winter I might pull the cam and swap it out but I will probably go with a Solid Roller and be done with it.
I got one run at the drag strip last week and my accelerator bracket broke,,, 114mph,,, 2.2 sec 60' and 12.8 et, on a 90 degree day at 2:00pm. I'll go again with the bracket fixed when the weather is cooler.
Is the low trap speed due to the weather? Or this what what you expected. A friend's 01 Z06 which is 100% stock traps 113-114 with 341rwhp/337rwtq. I thought you would be in the 118 mph range.
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Great, we are going to Muncie tomorrow/Wednesday night!
Quote: Is the low trap speed due to the weather? Or this what what you expected. A friend's 01 Z06 which is 100% stock traps 113-114 with 341rwhp/337rwtq. I thought you would be in the 118 mph range.
My best trap speed was 116 with the MR but, I'll know more tomorrow night when I go abck toteh track.
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Post the dyno sheet!
John
Last edited by JOHN89; 10-09-2007 at 09:02 PM.
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Dyno sheet is in my pics, it made a 405 on the pull before this print off, this was the last one. It was in the high 90's and very high humidity that day too. I wouldn't be surprised if it made 5-10 more on a cool dry day.
Never had it on a 1/4 mile. I tried it on the 1/8 mile not longe after I had it tuned and the track was very slick (hot & humid), and I just kept spinning through the first 2 gears, plus I have street tires. Going to try again when it gets down into the 50s or 60's, but I think on the longer 1/4 is where it will really show it's potential, although I am not a drag racer, and it's set up more for twisties than drag.
Never had it on a 1/4 mile. I tried it on the 1/8 mile not longe after I had it tuned and the track was very slick (hot & humid), and I just kept spinning through the first 2 gears, plus I have street tires. Going to try again when it gets down into the 50s or 60's, but I think on the longer 1/4 is where it will really show it's potential, although I am not a drag racer, and it's set up more for twisties than drag.
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I forgot you go to Muncie. That's an awlful long drive from Greenwood.
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Heads are AFR 210's, valves are back cut and the intake ports were smooted out
Cam is a HR 233/233,,, .576 lift w/1.6 rr's, 284/288 duration
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hi larry,
this is the cam im going to go for with my new 8 t/b intake
#07-467-8
comp cam hydraulic roller cam,
242 intake,248 exhaust duration @ .50 "
292 intake,300 exhaust advanced duration,
584/579 lift running 1.6 ratio rockers
113 lobe seperation
rev range 2,200 - 6,400 rpm.
still quite agreesive cam i reackon.
cheers
shae
this is the cam im going to go for with my new 8 t/b intake
#07-467-8
comp cam hydraulic roller cam,
242 intake,248 exhaust duration @ .50 "
292 intake,300 exhaust advanced duration,
584/579 lift running 1.6 ratio rockers
113 lobe seperation
rev range 2,200 - 6,400 rpm.
still quite agreesive cam i reackon.
cheers
shae
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Did not make it to the track,,,, evidently the single run I did last Friday tore up the clutch disc,
when I fired up the car yesterday, I noticed a vibration when I reved the car, and I recalled major organic clutch disc smell after my run last week.
This morning I called Doug @ RAM and they said " the organic disc that I have is good for 600-HP", and BTW, RAM will not warranty the disc because I only bought their PP and Disc, and I DID NOT buy their Flywheel, and it is past the 30-day point"
So RAM is a
company and their claims of 600hp is
Gonna pull the tranny out Saturday and take the disc out and send it to Summit Racing, where I bought it, and let them deal with it.
I have a spring Hayes Puck Clutch with ceramic pucks in the garage, I'll probably put that one in and see what it does.
when I fired up the car yesterday, I noticed a vibration when I reved the car, and I recalled major organic clutch disc smell after my run last week.
This morning I called Doug @ RAM and they said " the organic disc that I have is good for 600-HP", and BTW, RAM will not warranty the disc because I only bought their PP and Disc, and I DID NOT buy their Flywheel, and it is past the 30-day point"
So RAM is a
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Gonna pull the tranny out Saturday and take the disc out and send it to Summit Racing, where I bought it, and let them deal with it.
I have a spring Hayes Puck Clutch with ceramic pucks in the garage, I'll probably put that one in and see what it does.