LE3 dyno results, not happy. Thoughts?
04-23-2012 | 03:49 PM
#21
FWIW, I dynoed my car after I ran an 11.4@118 with a 1.579 60 ft @ 3650 raceweight and it only made 355rwhp and 360rwtq. This was a 11.5 355lt1 with gtp lt4 stage 2 ported heads and intake, 236 242 112lsa cam with a th400, 9" rear with a nitrous converter.
Like the other guys said, don't be upset until you run it. I would have figured a 35-40rwhp gain at most from just a head and intake swap while leaving everything else the same. Now if you put in a much bigger cam you could expect 60-80rwhp depending on how radical you go with the cam.
Like the other guys said, don't be upset until you run it. I would have figured a 35-40rwhp gain at most from just a head and intake swap while leaving everything else the same. Now if you put in a much bigger cam you could expect 60-80rwhp depending on how radical you go with the cam.
04-23-2012 | 05:49 PM
#23
Thanks guys, I guess I'm one of those guys who always has good advice but can't follow it himself lol. I've also always said the same about dyno numbers vs. track times, but then when it comes down to my own car, I got caught up in the "dick comparing contest".
I do have a track somewhat close and will try to get there soon. I'm also going to do the things Dave from Yank told me to do to try and verify the stall speed
I do have a track somewhat close and will try to get there soon. I'm also going to do the things Dave from Yank told me to do to try and verify the stall speed
Last edited by SprayedLT1; 04-23-2012 at 05:54 PM.
04-23-2012 | 08:18 PM
#26
That's actually a tight converter for that much cam, and very efficient. I wouldn't suspect it as being an issue.
That combo should peak around 6500. Hopefully the valvetrain is up to par for those heads and cam and you'll want to shift at 7000-7100 because that converter will pull it down to ~5200 in the next gear.
I agree with disregarding the numbers; I think a pessimistic dyno, your 9" rear, and not even revving to peak power all add up to make them irrelevant.
Just go run it
That combo should peak around 6500. Hopefully the valvetrain is up to par for those heads and cam and you'll want to shift at 7000-7100 because that converter will pull it down to ~5200 in the next gear.
I agree with disregarding the numbers; I think a pessimistic dyno, your 9" rear, and not even revving to peak power all add up to make them irrelevant.
Just go run it
04-23-2012 | 09:33 PM
#27
Like the guys above said, don't worry too much about the dyno numbers with an auto.
I saw a 30% difference (~300 vs 460) between locked and unlocked numbers with my first 383 build.
Use it as a tool to make sure things are working properly and leave it at that.
Good luck at the track; let usk now how it does.
I saw a 30% difference (~300 vs 460) between locked and unlocked numbers with my first 383 build.
Use it as a tool to make sure things are working properly and leave it at that.
Good luck at the track; let usk now how it does.
04-23-2012 | 09:44 PM
#28
It's ok I only made 358/350 
Tq falling off a cliff early, and all those bumps up top makes me think valve control issues. Clint ran a CC306 and may have some weeny springs on there. Just a thought?
Tq falling off a cliff early, and all those bumps up top makes me think valve control issues. Clint ran a CC306 and may have some weeny springs on there. Just a thought?
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04-23-2012 | 10:23 PM
#30
I bought the heads without springs, and put the PAC 1215 beehives on. The dyno operator said he didn't think the dip was valve float since after the dip it started pulling again. He said if it was valve float it would have just nosedived and dropped off sharply. That's why I was thinking opti
04-24-2012 | 12:21 AM
#31
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From: CT/NJ
I bought the heads without springs, and put the PAC 1215 beehives on. The dyno operator said he didn't think the dip was valve float since after the dip it started pulling again. He said if it was valve float it would have just nosedived and dropped off sharply. That's why I was thinking opti
Make sure they tuned it to all the way to 7k and then hit up the track. It looks like it runs fine, despite the spastic dyno sheet.
04-24-2012 | 01:47 AM
#32
I bought the heads without springs, and put the PAC 1215 beehives on. The dyno operator said he didn't think the dip was valve float since after the dip it started pulling again. He said if it was valve float it would have just nosedived and dropped off sharply. That's why I was thinking opti
04-24-2012 | 05:47 AM
#34
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Joined: May 2005
Posts: 349
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From: Mount Sterling KY
I bought the heads without springs, and put the PAC 1215 beehives on. The dyno operator said he didn't think the dip was valve float since after the dip it started pulling again. He said if it was valve float it would have just nosedived and dropped off sharply. That's why I was thinking opti
04-24-2012 | 09:07 AM
#36
I would suspect that insufficient springs might be limiting the motor the rev higher. I had similar springs on mine and power nose dived at 6K RPM. With better springs power held all the way to 6.5K RPM and I have a much smaller cam and heads. I dont really look at it as racing dynos etc. Its about seeing the curves, where they peak, troubleshooting and tuning. Thats about it.
