how to get above the 40hp mark on pump gas?

so what should i do? i allready have white bros. rev kit, yoshimura exhaust, k&n jet and filter kit............ i really would like to hit 40 hp and still be on pump gas so what do you guys recommend?

[MadcapEX]

Like I always say "If you want it to run, "ya gotta poke it & stroke it!":cool:

[MadcapEX]

I n laymans terms, bore it and stroke it.:eek:

[VegasEx'r]

Originally posted by MadcapEX
Like I always say "If you want it to run, "ya gotta poke it & stroke it!":cool:

Dude, I hope you are talking about an engine :D :rolleyes:

[VegasEx'r]

keep the compression below 11:1 & you shouldn't have a problem running pump gas. Get a bigger piston, a more agressive cam, stroke it if you want to, port & polish the head, get an FCR carb.

[MadcapEX]

:eek: :devil

ok i allready know i need to bore it and get a cam........ now what is going to be the best cam for drag racing?, and how about bigger bore kits there are just soooo many to choose from(416, 425 ,440), then what company has a good reputation for all this stuff? sorry for so many questions i just don't know what to do

[VegasEx'r]

The answers to your questions aren't that tough, but I do have to ask a couple of things first.
1) Are you going to do the work yourself or have a shop do it all?
2) What kind of budget do you have?

If money is no object, look up Chadex'er or Alky472 (I might be wrong on Alky's number). They have (or will have shortly) some bad machines. If you are a little more budget-conscious, you can do what a lot of people here have done. Get a 416 (or 425) piston w/ a 10.8:1 CR (going higher means having to use race fuel). Buy a cam. There are a lot of good ones out there. A lot of people use the xr cam because it is a "drop-in" cam. But you can also call up TC Racing, GT Thunder or Sparks. There is also a good cam from xr's only (the HRC Copy cam), or you could get a Web cam. The xr is good all around, and it is a "mild" modification (I have been impressed with mine). TC, GT & Sparks are all engine builders, and all 3 make great cams (from what I've heard & seen). I think they all focus on bottom to mid-range power. The HRC copy is a good mid to top cam. I have heard that the bottom end loss from these cams is negligable (sp?). Web makes some good cams, too. you can check out their site for more info. There are lots of others, and I am sure that other people will point out that I have forgotten them. Decide where you want your power, and that will limit the selection. From there, I don't think you will go wrong with any of these cams.

Anyway, adding the piston & cam will probably put you just shy of 40 hp. Try a port & polish job, maybe a 3-way valve job, too. You could also get larger intake & exhaust valves (just make sure to buy them before you have any head or valve work done). You can also buy a 39 (or 41) mm FCR carb.

Lots of info, hope I didn't bore you.

[NJ300ex]

just putting an 11:1 piston in a 400ex is really around 10:8. You can get higher compression than that and only have to mix race gas with 93 octane. Depending on what octane of race gas you use you can probably go up to 12:5 comp piston with a mix of pump and race gas. This would cost alot less than running straight race gas. Just a suggestion:)

[NJ300ex]

Also you could easily get above 40 hp by doing everything possible to the engine while retaining a lower compression piston.

Get the ct racing 440 midrange kit it makes 39 hp with the stock carb. With the fcr 41mm carb its makes 42-43hp and all on pump gas.

good info........... and no its not a bore

although i do hear if you do a 440 there is a possiblility of overheating problems...... can you explain this?

i do have the service manual..... is it hard to break the top end down?

[PDunes300ex]

Just get a turbo :blah

[nakomis0]

If your mechanically inclined and can understand your manual decently. Than it shouldn't be to overwhelming of a job. I did all my work myself, except the valve work and porting, and it turned out fine.
And 440's get really hot. probably the bigger bore the better for drag racing..

so how would i know if its running too hot........ would you say the 440 kit is not for me?

[Chef]

The perfect setup for pretty fast quad on pump gas would be the 10.8:1 416, FCR39 carb, Web 479 cam, and a powroll airbox lid. This should get you there. If you dont have a pipe already a white brothers slip on works really good with this setup. I have a friend with two of these exact setups..

[VegasEx'r]

When you go with a larger bore, it will generate more heat because there is less material in the cylinder, so it takes longer for the heat to dissapate. This heat is what can kill a motor, since you sacrafice displacement for reliability. BUT, I have never seen or heard of a 440 (or even larger) cc ex burning up until today. Alky472 had some problems, but that was because the carb wasn't dialed in. That could happen to any quad, even a stock one. People talk about the big bores being less reliable, and while there is some truth to that, I don't think it is much to worry about, so long as you take care of your quad. I recommended the 416 or 425 because it is cheaper. It isn't too tough to do the work yourself either. Just be careful removing & reinstalling the 6mm head cover bolts. I think that all of the heat weakens them, so thay can break easily, so use some good assembly lube on them. Also, don't let the cam chain fall down in the case (duh). Buy a torque wrench if you don't already have one.

so whats the main differences between the 416 and 425 kits, well i know obviously the displacement, but is there any thing else?

also where is a good place to buy these kits?

TIA

[Texan32]

the 416 is the stock sleeve bored 80 out.
the 425 is the stock sleeve bored 120 out which i've heard thats as big as the stock sleeve can be punched
pretty sure this is the difference

[ChadEXer]

Yes that is correct, then with the 440 you have to get a new sleeve. A lot of people on here are buying there kits from Marcums(877-264-3409) he will hook you up with a kit for a great price!

[VegasEx'r]

Texan is right. I guess that a 425 would make more power, but not much more, since it is only 9cc bigger. It also probably runs a couple of degrees hotter. Again, not a big deal. I think that most 416 & 425 kits cost about the same, it just kinda depends on what is available.

so about how much do these kits run?\

some web sites would help TIA

[ChadEXer]

You can get any kit you want from Marcums for about $300. im not sure what all kinds of cams he can get but he can prolly get anything!

[VegasEx'r]

Yeah, Marcum's is your best bet for the 416 kit. He will get you a JE 10.8:1 piston, xr cam, Cometic gaskets & Viton valve seals for about $275. ANother place you might want to look at is Heterick Racing, I think they have a good deal, too. Other places are TC racing, Sparks or CT Racing. GT Thunder sells cams (not sure about pistons). Check the links page up top for all of these web sites.

[TrX465]

i can tell you how to get 60 :) but then youd be running alky and ewwwww my nitrous kit is here :eek:

[ChadEXer]

I smell somethin burnin':D :D

[TrX465]

$5 says i make it work perfect ????any takers and it will work well as im beating all your asses up the hill hahahah just messin i hope i dont **** it up to bad :)

[mopar 400]

The 416 kit with your choice of cam is the way to go for the least amount of dough. Just got my 416 kit, xr cam, viton valve seals, cometic gaskets, and all the help I need (just call Terry!), for $266.50, shipped to california. I will be getting the quad on a Dyno around the 10th of May, and will post the HP on here once I am done. Also gettin my DR exhaust ceramic coated as we speak, hope to hit high 30's or low 40's when all done.

[Chef]

hey TrX465...if I ever end up with Nitrous I'm a taker on a run against you up the hill...:D ;)

[ChadEXer]

I dont think a 416 with XR cam would hit the 40HP mark! Maybe with a bigger carb, port & polish, and the complete works it might get close but i dont think it will
Alky and TRX465 are gonna be smellin' VP c14 all the way up the hill:D I just love this mine is faster than yours stuff. by the way guys,,,my dad will beat up your dads too:D

[TrX465]

naw im just messin it would be bad though go gang up on all the raptors and chase down the banshees.....all you hear is rumbling awwwwww go to love it :)

[ChadEXer]

They said those 465's will beat most Banshees didnt they??? i cant wait to get this damned motor back. the feeling is like having $1,000,000 in your pocket but you cant spend it!!!!!!!!!

yeah i don't think an XR cam can produce high hp more like a track cam

[Chef]

Originally posted by ChadEXer
I by the way guys,,,my dad will beat up your dads too:D

lol...i dont know...i bet my dad has faster toys!