3.0 Engine low power problem

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02-21-2018, 01:07 PM
fourcanfinder

3.0 Engine low power problem

Hi all, hope I can pick some brains!
I have on the bench a 3.0SC motor, RSR mahle 95mm high comp pistons, SC heads, ported, compression ratio works out around 10.1-1, DC80 cams, high butterlfy MFI. Single plug, tuned length headers and a rear box with no internals.
Engine makes 200 hp on a dyno with a big flat spot at 5000rpm, pulling my hair out with it, could it be an exhaust issue? Or inlet? Or just a bad missmatch?
Initially thought low compression with a 90cc SC head but ratio is up. Pump has been re-done.
I'm tempted to fit a set of carbs and standard SSI set up to see if I get any better results? !
Cheers in advance.
02-21-2018, 01:18 PM
Chuck Miller

Hmmm... I'll let the pros weigh in... however if you're in my state of CA at 10.1 with single plug, you may be run'n into an octane issue... just say'n

We'll see what the pros say...

Good luck,
cm
02-21-2018, 01:36 PM
gled49

Who did the pump, and to what spec? Gordon
02-22-2018, 12:02 AM
NZVW

Quote:

Originally Posted by gled49

Who did the pump, and to what spec? Gordon

2nd that

Flat from 5k to ?? or just flat from 5000

Mark
02-22-2018, 03:34 AM
edmayo

And you've checked your total ignition advance ?
02-22-2018, 04:02 AM
Frank Beck

Please post the dyno sheet otherwise this whole exercise is a comedy routine.

Thanks.
02-24-2018, 07:49 AM
ST harry

DC 80???? The Konfiguration is mayby not perfekt? Take vor this a S Cam.....
02-24-2018, 11:21 AM
edmayo

Broken valve spring??
02-27-2018, 01:44 AM
Frank Beck

Still waiting for dyno sheet.

I do hope the OP updates his post. Nothing more frustrating than someone seeking free advice then disappearing. When that happens one can only assume someone was stupid and embarrassment soon followed.