Yes, We gained 61 hp over a stock 525. It would continue to make power until the hydraulic lifters would give up. Right around 6000 rpm. Getting ready to put them back in the boat and see what kind of real world gains we get.

Did you gain 61hp over the rated 525 HP or did you dyno first ?

Reason for asking is that shops that have dyno'd the stock 525EFi have found 540-560hp depending on the tune.

Here is a chart from Whipple that shows what I'm talking about:
http://whipplesuperchargers.com/inde...product_id=113

Yes it was from a dynoed engine.

Keep in mind Scott that 99% of aftermarket dyno operators use J607 correction factor vs SAE 1349, solid 3.9% difference in that alone from mercruiser to your local dyno. A 525hp motor becomes a 546hp motor . Same dyno, close to same conditions A-B test, THAT gives real results

Were you able to shift the HP peak from that 5400-5600 range to 6000 or did it carry to 6000? Send me a message or give me call if you still got my phone number, would love to hear what you saw, Smitty

Yes...and that's why I want to make sure he got the gain as stated.
Apples to apples is what we want. Be it 10 hpm 20hp, or 60hp or more.

Yes they were apples to apples.the were the uncorrected numbers. The weather was so good the correction wasn't changing it more than a couple hp. It made 40 hp more straight off the start. Then with some tuning we ended up with the 61. And yes it kept pulling all the way to 6000. I would really like to see what it would do with a big cid motor.

Did you give up any torque anywhere? I'm still in the planning stages on my 500 efi project, left my 500efi's in my boat for this summer stock aside from tuning because busy doing other stuff on my dyno and didnt want to have boat apart come boating season. I did buy a unmolested 500 efi intake and my intentions are to get a spare 502 short block, put my 400+cfm AFR cnc'd heads on it, get 2 or 3 different cams from Bob Madera, put intake on in stock form and dyno it . I'm then going to install TPI's throttle body on it, re-dyno it and tune it, see where its at. Then have tpis do their plenum mod where they extend front of plenum susbatntially, see where its at tq and hp wise. Then pull plenum and intake off, cut dividers in plenum out, mill lower intake didviders down to where its only 13-13.5" to head of intake valve in a attempt to raise hp peak to past 6000. IF at some point it starts to give up useable tq make a judgement call of how far to mod the 2 intakes on my boat when I do the motors. If I cant make 650 hp I'm tossing it all and putting aftermarket intakes on it, going to be a long project over the summer/fall and maybe into winter as I have to take motor off my dyno to do paying work too so it may get pushed aside at one point too. Glad to hear you got it to pull to 6000, too bad you didnt have better lifetrs or whatever held you back, I have a set of morel high revs and isky solids left from my blower motor in my Baja that I have to use, I revved the 540 with the iskys to 6500 no problem last time I dynoed it and the Morels to 6300 so it shouldnt be a issue, Smitty

[SUB][/SUB]Stock 525 Cam?

Mark Rinda recently did some 525 work and with throttle body mod, some plenum work and some lower porting got a 525 to carry with a slight drop off to about 6000 but it still peaked in that stockish rpm range as far as rpm's. Like I said, I like to get one to peak at 6000, maybe even 6200/6300 and carry even further .
CIM-you also increased plenum volume susbatntially past the stock 325 or so sq inches if I recall?