saving for a 416 kit?

[yellow400ex05]

I want to get a 416 kit sometime during the summer and was wondering how much I would have to save up, also what compression would I need in order to still run pump gas at 93 octane?, I heard 11:1 is good, but I'm not sure. Give me some info. Also who sells the 416 kit? I see on Powroll that they have a 415 kit but I'm just wondering if thats any different than any other sites saying its a 416 kit or its just how they are advertised? thanks

[zrpilot]

Check with Colby here at C&D, great prices and he has built a few, so he will be able to tell ya what to get.

I general though an 11:1 should be able to run on good pump gas. I see you've got a pipe and a cam, if I were you I'd think about a couple more items:

HD head studs
CRF 450 cam chain
head porting
New CDI

[downeyballz]

piston kit would be cheap like $200 total. all you need is a piston, gasket set, and machine work. i would go with 11:1, but heard the weisco pistons had the wrong wrist pin height giving you lower than stated comprssion. so you might want to shave your head/ cylinder to bring the ompression up a bit. cheap mod

[greyyfz450]

how much do you bore out a motor to make it a 416 because i have a xr 400 and i have got it bored .50 over?

[JW450R1]

From what i've been told .80 over.

[zrpilot]

I got mine 1.0 over...LOL

[Chino886]

Originally posted by zrpilot
Check with Colby here at C&D, great prices and he has built a few, so he will be able to tell ya what to get.

I general though an 11:1 should be able to run on good pump gas. I see you've got a pipe and a cam, if I were you I'd think about a couple more items:

HD head studs
CRF 450 cam chain
head porting
New CDI


I agree with these extra items of insurance that ZRpilot has suggested!

If you want to save a few bones, I have a Sparks 416 piston that has probably less than 2 hrs on it! Only want $60 shipped for it, but I think the compression is higher then you are wanting.

As far as octane, I ran mix of 111 and 91 to achieve about 105 to aid in engine temp and to prevent deto! :p

[Colby@C&DRacing]

Our JE 416 is $120 gasket are $40, cam $136, valve seals $5 and exhaust gasket are $4.20. We charge $60 to bore the cylinder. Hope this helps :)

[04TRX400EX]

There ya go ^^^^ straight from the source. Wiseco's 416 bore states 11:1 but as downeyballz said, you may not actually get that. I would go with a JE kit - 10.8:1 comp and the highest quality. A buddy of mine has the exact kit Colby posted and that thing is so much faster than my "stock" 400. He also has a FCR carb on his which you may want to consider.