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tri5ron
06-26-2008, 11:03 PM
I was looking at the dyno specs on the Hot cams website, and wanted to get some clairification, or correct me if i'm wrong,...

it seems to me that a stage one Hot Cam,
on a basically STOCK engine,

is only gaining 1 HP over stock?
am I reading the scale correctly?

and it seems to me that the power curve is only slightly improved. am I reading the dyno scale correctly? or am I pulling some major brain-fart here?

My Engine is basically stock.
I have a Big Gun full system, jetted, no airbox lid, K&N w/Outerwears, and a Sparks +6 Advance Key.
I still have the choke plate in, on the stock carb.

So, how much benefit would I gain from a stage I cam,...

or can a basically stock engine,(with the above listed add-ons), make use of a stage II cam?
(and what would the differences be as far as gains go)

I don't ride any tracks, and am generally using my quad for open desert, recreational riding. (but I do occaisionally like to rip it up).

zrpilot
06-26-2008, 11:17 PM
tri5ron,

IMO the stage 1 is a better choice for a stock engine. I'm afraid that you would lose too much dynamic compression with the stage 2 and the stock compression ratio. Check out this post by GPracer2500 sometime ago:

"I see a lot of discussion about the HC stage 2 vs. the HC stage 1 for a stock compression engine. I've done some calculations to define how much the stage 2 might hurt bottom end performance. If you read the entire first post then you know that the issue is the loss of compression from the intake valves staying open a long(er) time. Compression is a dominating factor for producing low end torque. Here's the difference:

Taking into account the valve specifications:

Stock cam cranking compression at 1000ft = 8.2:1
HC stage 1 cranking compression at 1000ft = 7.8:1
HC stage 2 cranking compression at 1000ft = 7.6:1

If you go to a 11.0:1 piston (instead of the stock 9.1:1 piston) then the numbers change to:

stock cam: 9.9:1
HC stg 1: 9.5:1
HC stg 2: 9.2:1

(figures may not be absolute but the comparison is accurate)"

Thanks GPRacer2500!!!

blaaze416
06-26-2008, 11:18 PM
Hey tri5ron, thanks for the sparks timng key write up! It really came in handy!!As for the stage two with a stock engine.....I think you'll benefit more from the stage1. Without a higher compression ratio, such as 11:1, i think the stage two might be overkill. For a stock ride, if you want a cam, get the stage one. I got the stage two cause I knew I was going to an 11:1 416. eventually. As far as gains go, I always end up doing more than one thing to my quad, so it's hard to tell where the power comes from. Dont mean to lead you in circles. :ermm:

blaaze416
06-26-2008, 11:20 PM
Damn ZR, you da man!

tri5ron
06-27-2008, 12:09 AM
thanks guys,
That pretty much confirms what I was thinking.

So am I correct in reading the dyno comparison scale, that the stage I only gains about 1hp ? and the curve is only SLIGHTLY improved?

also, I am a firm beliver in the Einstein theory of,...
"for every action, there is an equal and opposite reaction".

and if that is so,... then my question becomes,
What am I giving up to accomplish these small gains?

BTW- Yeah, I realize that the gains would be signifcantly increased, if I were to go to a higher compression piston,...

But I'm of the mindset that I like to get the most use possible out of the stock bore, before I go hogging it out to a bigger size, and thinning down the cylinder walls, before it really needs it.

(damn thing already goes fast enough for me now,....
I've just got a bad case of the A.A.D.S. thing going right now...)
:D :D :D

DementeD
06-27-2008, 07:16 AM
also note on the 400ex cam setting..the dyno is showing the xr400 cam..NOT the 400ex..

not sure the difference but i know ive seen a lot of people switch out the 400ex for the xr400 so im taking it as its a better cam
so the difference im sure will be larger for the hotcam in a 400ex..

also you dont get to see the tq curve so u dont know how great the cam will do overall

another thing u see the power has pretty much the same curve but the fall off is a little later in the powerband and stays higher then the xr cam which i also think ull notice a good bit

DementeD
06-27-2008, 07:35 AM
figure id post the difference in the stock 400ex cam and the xr400 cam along with the stage 1 cam from hotcams

Stock TRX 0.316 0.302 234 238

Stock XR400 0.326 0.321 240 244

Hot cam stage 1 0.354 0.354 246 246

Hot cam stage 2 0.354 0.350 254 248.5

so as u can see the hot cam vs 400ex is a big difference
where as compared to an xr cam the difference isnt that large but still more impressive and i went ahead n threw in the hot cam stage 2 so u can see the difference there as well..

tri5ron
06-27-2008, 11:43 PM
Thanks DementeD,
You always are good for getting real and useable info.
I appreciate your effort and input.

cbr929rr
07-06-2008, 04:47 PM
I have a xr400 cam, I plan on going with a 416 JE 11:1 piston with fmf powerbomb header and white brothers e-series exhaust and possibly an AMR monster coil to finish things up. I have everything waiting except the piston and coil. I have already dropped a tooth on the front a rejetted with the e-series. I want bottom end like crazy, I do alot of tight technical trails in the woods and like to run second gear constantly and I want the bottom to explode in second gear when i need to slide or turn over rough terrain.

tri5ron
07-06-2008, 05:03 PM
Thanks again guys,
here's another question...

I've heard that when you change to a HC1 (or HC2 for that matter), it will no longer use the de-compressor valve.
why is this?

what are the advantages and/or disadvantages to eliminating the use of the decompressor valve?

HondaRaceReady
07-06-2008, 06:19 PM
I've heard that when you change to a HC1 (or HC2 for that matter), it will no longer use the de-compressor valve.
It no longer uses the de compressor valve because you have to remove it to install the hotcam. Not sure about advantages/disadvantages though.

DementeD
07-06-2008, 08:49 PM
From what i read..the decompressor is needed to bleed the compression making the atv easier to start.
since the hotcam has a longer duration this part is not needed.

and it seems like because of this the advantage is an even easier start vs stock cam..

leechi
07-06-2008, 09:01 PM
in my proyect, when i was a chose a cam, i chose a stage 1

why?

i like a daily ride and a track ride....whit the trust of the honda engine...

and i think whit the stock internals and stock compression, the stage 1 are better....because is more dynamic and progresive

i think that stage 2 is better from 416 strokers or/and high compresion engines, and it really works great the stage 2

i think that the powerband of the stage 1 is more use that stage2,
why? because never i ride at wot, in a track whit stock engine my body canĀ“t use to full thotlle... one use more low and midle........

if my think wrong tell me please!!!!

i like listen yours!!!

(sorry of my bad english)