379cc Raptor 350 in progress

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I believe I have talked to an expert that does this for a living. So how can I possibly go wrong ?

The mechanic that is doing the buildup for me has had a few race cars and always did his own mechanic work and tunings and has a few trophes to prove his wins. He also fixes Turbo's and **** for a living. So I got 2 experts with me, so I guess i'll be ok. Thankx for worrying though.:tup:
 
I'd argue the guys on here have more experience with this specific motor though. Almost everything has been tried here, good or bad. Seems like a lot of money to put into something to be possibly disappointed is all.
 
lbswut said:
i'd argue the guys on here have more experience with this specific motor though. Almost everything has been tried here, good or bad. Seems like a lot of money to put into something to be possibly disappointed is all.
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+1000
 
Lbswut said:
I'd argue the guys on here have more experience with this specific motor though. Almost everything has been tried here, good or bad. Seems like a lot of money to put into something to be possibly disappointed is all.
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Let's just wait and see... I'll post a video on the stock 350 motor and after the tuning is done.
 
beastlywarrior228 said:
I believe a study i saw before for warrior heads that on an unported head you dont see any more flow once you get past .390 lift
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Its true thats what I started with and sent my head to Eric Gorr and he did the porting and polishing and valve job + 1 on intake and a .MegaCycle 252x-2 Mid-range cam
Intake .415" / Exhaust .395"
 
Ill bet you100$ walle and all 348cc will outrun, and out pull your stroker with the setup your talking.

To get all you are wanting out of that you will need a lot of port work, a better carb as I mentioned earlier and a good intake would be good.

Otherwise your just building a less then exciting stroker
 
duneracerweston said:
Ill bet you100$ walle and all 348cc will outrun, and out pull your stroker with the setup your talking.

To get all you are wanting out of that you will need a lot of port work, a better carb as I mentioned earlier and a good intake would be good.

Otherwise your just building a less then exciting stroker
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Well let's just wait and see :tup:
 
Fact, a higher duration cam movea the torque curve up in rpms. Fact, the factory cylinder head does not flow well enough to support high rpms. Fact, more displacement does tame camshaft aggression, however we are talking 29cC's, not a HUGE gain. Fact, lower compression engines work well with camshafts that increase low rpm cylinder pressure. Too much compression with a mild cam builds enough compression to cause issues. Fact, longer duration cams naturally create overlap, it's their nature. What does overlap do? Overlap bleeds cylinder pressure, in done cases you can actually hear the X compression bleed into the exhaust. Fact, when you start with an engine that has a low static compression ratio (9.2:1) and you add a"big" cam, you suffer a tremendous loss in usable cylinder pressure, therefore a loss in power. Fact, if you do not have sufficient enough cylinder head flow to support the power band in which your camshaft will make peak torque then your engine suffers andyou WILL NOT see the performance that you desire. I'm not a novice either friend, your stubbornness will not be beneficial to you.
 
'00 WO-YA! said:
Fact, a higher duration cam movea the torque curve up in rpms. Fact, the factory cylinder head does not flow well enough to support high rpms. Fact, more displacement does tame camshaft aggression, however we are talking 29cC's, not a HUGE gain. Fact, lower compression engines work well with camshafts that increase low rpm cylinder pressure. Too much compression with a mild cam builds enough compression to cause issues. Fact, longer duration cams naturally create overlap, it's their nature. What does overlap do? Overlap bleeds cylinder pressure, in done cases you can actually hear the X compression bleed into the exhaust. Fact, when you start with an engine that has a low static compression ratio (9.2:1) and you add a"big" cam, you suffer a tremendous loss in usable cylinder pressure, therefore a loss in power. Fact, if you do not have sufficient enough cylinder head flow to support the power band in which your camshaft will make peak torque then your engine suffers andyou WILL NOT see the performance that you desire. I'm not a novice either friend, your stubbornness will not be beneficial to you.
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Wow I love this ******* forum . You guys are so knowledgeable.
 
So it's pretty much point less to put in a cam in without head work is that correct ??

Newbie just trying to suck this all in correctly
 
'00 WO-YA! said:
Fact, a higher duration cam movea the torque curve up in rpms. Fact, the factory cylinder head does not flow well enough to support high rpms. Fact, more displacement does tame camshaft aggression, however we are talking 29cC's, not a HUGE gain. Fact, lower compression engines work well with camshafts that increase low rpm cylinder pressure. Too much compression with a mild cam builds enough compression to cause issues. Fact, longer duration cams naturally create overlap, it's their nature. What does overlap do? Overlap bleeds cylinder pressure, in done cases you can actually hear the X compression bleed into the exhaust. Fact, when you start with an engine that has a low static compression ratio (9.2:1) and you add a"big" cam, you suffer a tremendous loss in usable cylinder pressure, therefore a loss in power. Fact, if you do not have sufficient enough cylinder head flow to support the power band in which your camshaft will make peak torque then your engine suffers andyou WILL NOT see the performance that you desire. I'm not a novice either friend, your stubbornness will not be beneficial to you.
Click to expand...

Dude get your facts right ! I asked Greg what would HEEEEEEEE recommend... HEEEEEEE recommended the .450 CAM cause of my riding style. (SOFT SAND) The dude is suppose to know his **** ! He has been working in these motors for decades now ! And I asked him, will all these drop in be ok ? HEEEEEEEE said YEP! You are not going with a Big Bore so this will be good! Give him a call and give em all the tech talk you are giving to me. And proove him wrong!

Funny thing is, a guy here on this webpage told me talk to Greg for my 379cc build! So i did!
 
Dude you have got to try to have trust in these guys... They've done a lot more trial and error on this engine platform than most people have ever... And not only that but you seem like you think that they are engine dumb and don't know what they are talking about. But they do. I too feel like there was a miscommunication there with that guy, that is a very low compression piston and they are known to be bad in these engines; but I trust these guys. They have done a lot more than you may think. You most likely won't get the performance you are looking for and will be disappointed. We aren't trying to dis your setup just trying to help you get the performance you desire.

Oh and I personally don't care what one guy says when you have a WHOLE WEBSITE DEDICATED TO YFM350S telling you opposite!
 
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alex456123 said:
Dude you have got to try to have trust in these guys... They've done a lot more trial and error on this engine platform than most people have ever... And not only that but you seem like you think that they are engine dumb and don't know what they are talking about. But they do. I too feel like there was a miscommunication there with that guy, that is a very low compression piston and they are known to be bad in these engines; but I trust these guys. They have done a lot more than you may think. You most likely won't get the performance you are looking for and will be disappointed. We aren't trying to dis your setup just trying to help you get the performance you desire.
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I never said anyone here was engine dumb! I know these people have tried it all... And I came off a Raptor 700 and got a 350 just want a little bit more out of it. I asked my questions and somebody told me well talk to Greg ! That's what I did ! If Greg is wrong well i'll be the first one to tell you guys.
 
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