Dyno after mods...low numbers?
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
Dyno after mods...low numbers?
I had my car dynoed after I did a few mods and thought it seemed a little low. I had my car dynoed last summer and made the same I am at now, why is this with these setups?
03 C5 Z06
Stock LS6 heads
double springs
Harland Sharp 1.7 rockers
233/239 TSP Cam 112LSA
ls2 timing chain
ls6 ported oil pump
Vararam air intake
25% Underdrive pully
Bassani 421 headers with x pipe and GHl exhaust
New plugs and wires
180 stat
With that setup I made 399rwhp. Is this low?
Last summer I made 398rwhp and I had a 216/224 113lsa cam and stock harmonic balancer.
Would a 160 stat make that much of a difference?? What is the culprit?
03 C5 Z06
Stock LS6 heads
double springs
Harland Sharp 1.7 rockers
233/239 TSP Cam 112LSA
ls2 timing chain
ls6 ported oil pump
Vararam air intake
25% Underdrive pully
Bassani 421 headers with x pipe and GHl exhaust
New plugs and wires
180 stat
With that setup I made 399rwhp. Is this low?
Last summer I made 398rwhp and I had a 216/224 113lsa cam and stock harmonic balancer.
Would a 160 stat make that much of a difference?? What is the culprit?
Last edited by Sidieux; May 10, 2011 at 04:35 PM.
Le Mans Master
Joined: Aug 2007
Posts: 6,473
Likes: 297
From: Orange Park FL
I had my car dynoed after I did a few mods and thought it seemed a little low. I had my car dynoed last summer and made the same I am at now, why is this with these setups?
03 C5 Z06
Stock LS6 heads
double springs
Harland Sharp 1.7 rockers
233/239 TSP Cam 112LSA
ls2 timing chain
ls6 ported oil pump
Vararam air intake
Bassani 421 headers with x pipe and GHl exhaust
New plugs and wires
180 stat
With that setup I made 399rwhp. Is this low?
Last summer I made 398rwhp and I had a 216/224 113lsa cam.
Would a 160 stat make that much of a difference?? What is the culprit?
03 C5 Z06
Stock LS6 heads
double springs
Harland Sharp 1.7 rockers
233/239 TSP Cam 112LSA
ls2 timing chain
ls6 ported oil pump
Vararam air intake
Bassani 421 headers with x pipe and GHl exhaust
New plugs and wires
180 stat
With that setup I made 399rwhp. Is this low?
Last summer I made 398rwhp and I had a 216/224 113lsa cam.
Would a 160 stat make that much of a difference?? What is the culprit?
Thread Starter
Advanced
Joined: Sep 2009
Posts: 95
Likes: 0
From: Pittsburgh/Butler PA
First was it the same Dyno ? Mustang or Dyno Jet ? Were the dyno results output in the same format (SAE corrected, Std..ect) ? Did you make more than one pull (wondering if the motor was hot enough) ? The LS motors like to be at least 185 degrees from what I hear. There could be alot of different factors. Do you have the same rear tires and rims ? Heavy after market rims will kill ya on the dyno. Do you have bigger tires now ?
Last summer I had CCW 505a 19x11 with nitton invo tires. Now I have 19x11 c6z chrome ones as I got sick of cleaning the 505's for a DD. I now have hankook v12 on them.
Last summer was on a mustang dyno, this time it was on a dynojet. So this is normal, I didnt really gain any HP with the bigger cam?
Le Mans Master
Joined: Aug 2007
Posts: 6,473
Likes: 297
From: Orange Park FL
I forgot to add. Last summer I had stock harmonic balancer, now I have a 25% under drive one.
Last summer I had CCW 505a 19x11 with nitton invo tires. Now I have 19x11 c6z chrome ones as I got sick of cleaning the 505's for a DD. I now have hankook v12 on them.
Last summer was on a mustang dyno, this time it was on a dynojet. So this is normal, I didnt really gain any HP with the bigger cam?
Last summer I had CCW 505a 19x11 with nitton invo tires. Now I have 19x11 c6z chrome ones as I got sick of cleaning the 505's for a DD. I now have hankook v12 on them.
Last summer was on a mustang dyno, this time it was on a dynojet. So this is normal, I didnt really gain any HP with the bigger cam?
I lost 17 rwhp with different wheels/tires on my Silverado. I was 465 on ET Streets and then went to 448 with the heavy street tires.
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
Your dyno numbers don't make sense as the Mustang Dyno reads lower than a Dyno Jet. If the Mustang was accurate, your new Dyno Jet numbers should have been a lot higher. Also, those chrome wheels are probably a lot heavier than the CCW wheels. That would have dropped the numbers some.
I lost 17 rwhp with different wheels/tires on my Silverado. I was 465 on ET Streets and then went to 448 with the heavy street tires.
I lost 17 rwhp with different wheels/tires on my Silverado. I was 465 on ET Streets and then went to 448 with the heavy street tires.
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From: At the beach in little Rhody
I think your original numbers were high myself. I had a 216/224 cam with headers and Dart heads and made 390 on a Dynojet. Also, was the 216/224 a Crane cam? If so, the ramp rates are slow and if the new cam is an XER then the old numbers are definitely off, especially on a Mustang.
How does the dyno curve look, any dips? The Hardland Sharps can produce valve train issues.
How does the dyno curve look, any dips? The Hardland Sharps can produce valve train issues.
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
Why would harland sharp cause valve train issues? It was a crane cam it was paired with 1.8 rockers. NO dips at all on the graph.
Also, Vettenuts, what power are you making with your combo? That seems like a nice setup.
Also, Vettenuts, what power are you making with your combo? That seems like a nice setup.
Last edited by Sidieux; May 10, 2011 at 10:06 PM.
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Joined: Mar 1999
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From: At the beach in little Rhody
The Harlands tend to be a bit heavy and can cause some issues in the upper RPM. It will show on the dyno if you have a problem.
I suspected that the original cam was a Crane. Stick with the HS rockers as the shaft mounting is more stable then the stud mounts (Cranes).
I really think your original numbers are just off base and very high for that cam and Crane rocker setup based on my experience. I ran essentially the same cam with both stock 241 heads and then with Dart 205 heads. My 241 heads setup with the Crane cam was 370 on the Dynojet, the Darts raised this to 395 give or take a couple of hp on the same Dynojet. The Darts are about the same, maybe a teeny bit better than the 243's you have on your car, so the Mustang dyno I would have thought would come in below my Dynojet numbers.
You mention double springs, are these a carry over from the Crane setup? Are they Crane 832's? Do you have the graph? Reason for asking is there were issues with the Crane 832 valve springs and a harmonic right around 6,200 RPM. If you have that issue it will show on the dyno curve. I chased this issue for six months before I found out about the harmonic.
I suspected that the original cam was a Crane. Stick with the HS rockers as the shaft mounting is more stable then the stud mounts (Cranes).
I really think your original numbers are just off base and very high for that cam and Crane rocker setup based on my experience. I ran essentially the same cam with both stock 241 heads and then with Dart 205 heads. My 241 heads setup with the Crane cam was 370 on the Dynojet, the Darts raised this to 395 give or take a couple of hp on the same Dynojet. The Darts are about the same, maybe a teeny bit better than the 243's you have on your car, so the Mustang dyno I would have thought would come in below my Dynojet numbers.
You mention double springs, are these a carry over from the Crane setup? Are they Crane 832's? Do you have the graph? Reason for asking is there were issues with the Crane 832 valve springs and a harmonic right around 6,200 RPM. If you have that issue it will show on the dyno curve. I chased this issue for six months before I found out about the harmonic.
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From: At the beach in little Rhody
No, that graph looks good. I think the original dyno is suspect based on my results with nearly the same setup (my cam was on a 114.5 rather then the 113) and I wouldn't worry about it. You must feel a difference in the car when you drive it.
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From: Pittsburgh/Butler PA
So after they finished the tune up the car finished at 394. This seems very low to me regardless of what others are saying. The car drives great, so I guess I will just forget about it.
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