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My compression #s

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Old 04-14-17, 07:48 PM
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My compression #s

Front
Rear
Front, uncorrected
tell me what you guys think, the corrected numbers seem high and there's one odd pulse on the rear rotor, I think it was 88 psi uncorrected
Old 04-16-17, 07:16 PM
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Doesnt add up. Correction is off.
Old 04-17-17, 07:15 AM
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use my compression test compensation tool (Excel/Google spreadsheet) which is based on the correction formulas from the service manual https://www.rx7club.com/3rd-generati...urate-1099046/

If I put 231 rpm, 90psi, and 80 feet altitude (Houston), I get 94psi corrected.
Old 04-17-17, 09:21 AM
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Sweet! I'll plug em in when I get home. Thanks for the feedback. Think I should worry about that low rotor face psi? It's still within limits but the only outlier, I tested it twice and same result.
Old 04-17-17, 10:31 AM
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As long as you trust the psi reading and the rpm reading of the tester, you can calculate the rest. So use the correction tool I supplied and calculate the correction yourself.

the raw readings you showed in the screenshot for rear: 90,92,90 . 92 is within 2% of 90. I didn't see the full set of raw readings for the front rotor, but 88 is within 3% of 90. just get out a calculator and divide the outlier by the average of the other faces. or if you want to be really detailed, you can calculate statistics in excel (standard deviation, mean, etc) Personally I think if they're all within say 5 to 10% uncorrected on a given rotor it should be fine.

Last edited by arghx; 04-17-17 at 10:36 AM.
Old 04-17-17, 11:02 AM
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It would be interesting to hear back from rotarycompressiontester about the correction issue, I know they added that capability to the latest build and I was thinking about shipping my early build compression tester back to them for the firmware update. He is pretty responsive, if there is a calculation error going on I bet it would be fixed.

Last edited by jza80; 04-17-17 at 02:42 PM.
Old 04-17-17, 11:37 AM
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IN Who's tester?

Sending you private message me I want some more info please never seen one do that.

I will take care of the issue they are tested more than once before I box them up.

Thanks
Old 04-18-17, 11:11 AM
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Just to follow up, rotarycompressiontester.com got in contact with me and I'm gonna try to reset the tester and repeat the test, if the correction doesn't come in right he said he would replace the tester so over all, 10/10 would recommend
Old 04-18-17, 02:30 PM
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IN Tester

Just so everyone knows we believe he may have a bad pressure sensor inside the unit itself or may just need reset by removing battery.

I can only test them so many times and believe me I wouldn't ship you a tester reading a 150 psi we could only wish!

This is the reason I give you a warranty somethings are out of my control.

I will gladly replace his tester if the issue is not solved. I haven't sold 300 testers in the last year selling you guys junk and never will.

Any of you can always contact me on IG or Facebook at rotary compression tester or Steve Miracle on messenger I do all of this by myself so I will answer you ASAP.


Old 04-18-17, 05:21 PM
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After reading this thread, I also manually calculated the numbers generated by the tester I purchased from Steve. I spoke with Steve, and we both agreed that the tester seems to provide corrected values 5psi higher than manually calculated figures based on the altitude and rpm correction factors. Steve did offer to test the unit and fix/replace if needed. I will retest again and see what comes up; if the same issue persists, I will be sending mine in to get looked at.
Old 04-18-17, 10:31 PM
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IN Foxed

We took about 6 months trying to get this as close to foxed.ca as possible and tested where possible.

Why these 2 are acting stupid and the other 98 out of the first 100 aren't we are searching thru code to see if there is a bug somewhere we already made a couple fixes.

Pics of tester above Classified Performance who did the software thinks it actually calibrated itself below sea level from his location and made it go haywire.

He has wrote a new calibration program and fix to prevent this being a possibility in the future.

Here is a pic of a test on my S5 vert every tester I have shipped has been within 1-2 psi when tested or they get re-calibrated.

Changes in atmospheric pressure may also affect readings a bit and there is a 1% variance in the sensor itself.

Engine type does not really matter either it's @ 1psi difference between all rotor compression ratio's for 10a-Renesis.




If someone tells you they can build a tester that will match that compression calculator every time they are lying,

I apologize to both for having issues but I will make sure you both have working testers and I will pay shipping both ways.
Old 04-18-17, 11:43 PM
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Appreciate the commitment to a solid product, and interested in getting one for myself.




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