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panteramatt

50 rwhp!!!

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You'd have to do a whole lot to get 50hp out of a 400. Lets see, big bore/high comp piston kit, ported head, cams, race gas and bored carb, maybe even a stroked crank. My 426 with a 450 cam, no airbox, Uni filter and race gas is 46hp. My CRF with everything mentioned above except the stroked crank is 60hp :cry:

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Below is a link to dyno runs and specs on SFO's 54 rwhp 444. He managed 52 rwhp on pump gas using the stock cams (reindexed) and stock valve sizes. I built a similar combination using a 98 YZF400 and got similar results. We got to 444cc using the 426 rod on the 400 crank and 426 barrel overbored 2mm. This spring I'll be testing this combination with a new big center valve head using Kibblewhite parts, Hot Cams , and a new crank fitted with a Falicon CRF450 rod. Should be interesting. :cry:

http://www.four-stroke.com/Dyno_runs/SFO_index.htm

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Cool, so all I would need to make 444cc is a 426 cylinder bored out and rod? Are hotcams worth the price and will I notice a difference?

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Are hotcams worth the price and will I notice a difference?

We've installed a lot of them and we've never had a customer that wasn't totally thrilled with them. It's a great match for the big bore engine.

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But will I notice a big difference with hotcams on a basically stock 400? Also does the auto decompression make kicking it over easier?

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But will I notice a big difference with hotcams on a basically stock 400? Also does the auto decompression make kicking it over easier?

The Hot Cams are NOT a good match for a basically stock 400, you are much better off with the OEM cams.

Yes the auto-decompressor cam works wonders for starting.

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