cpi vs. shearer vs. rocket

[bansheejoel]

whats your guys opinion on what pipe is best for dune/hillshooting with a real aggresive dune port, +4 timing, v-force 3 reeds, 34mm carbs, cool head with 20cc domes, and possibly a 4mill crank? Deciding between cpi, shearer, or rocket. (small bore) Do any of these pipe companys make a spark arrestor for them or do i have to run the ugly ass POS sparkys? When is a dunable override needed?

 

Thanks

[duneblazer]

im going to say CPI's! everyone will have different opinions tho! CPI's have that little extra in the mid than shearers!

 

and rockets im not sure... would still be an awesome pipe! id PM LOCO, he had rockets on his 4mil and 10mil cubs

[Bansh-eman]

if your not doing mostly drag racing go with the CPI's. Rockets would never see any motor I build.

 

Once you start making higher HP your going to need a lockup, once you get that lockup on there you will notice its not the nicest thing to try and shift. A override goes hand and hand with the lockup IMO. You got to be careful backloading them, well I say careful but you can backload up to like 8k so you dont have to be all that careful, just be mindful of it I guess would be a better term to use

[brian]

I run CPI inframes and I like them.

I would like to try some shearers just to see the difference tho.

 

Once you start making higher HP your going to need a lockup, once you get that lockup on there you will notice its not the nicest thing to try and shift. A override goes hand and hand with the lockup IMO. You got to be careful backloading them, well I say careful but you can backload up to like 8k so you dont have to be all that careful, just be mindful of it I guess would be a better term to use

 

Sup Greg ?

Not to be a smartass, just curious, but I thought I have read that you could

backload a duneable override ?

[Bansh-eman]

I run CPI inframes and I like them.

I would like to try some shearers just to see the difference tho.

 

 

 

Sup Greg ?

Not to be a smartass, just curious, but I thought I have read that you could

backload a duneable override ?

you can backload them up to around 8k, the regular override is a differant story. For the Duneable they are more forgiving, but if to talk to WRC he will tell you that you dont want to backload over 8k.

[locogato11283]

id prolly just go ahead and run shearers. great pipe that should work well with that application. you might not give you as much on the bottom as cpi but youll have more on top. if you feel your bottom end is lacking with the shearers gear it down a little and youll still have a ton on top.

 

im not a fan of cpi in any way. i would never run them.

 

honestly on this setup id run the rockets. ive run them on a wide variety of motors and they perform well on all. problem is youll prolly never find a set of them.

[Wildcardracing]

I've never had an issue with the CPI's, I prefer them for an engine that will be dune ridden some. The Shearer's are worth some power but at a loss of low to mid power.

[spurdy]

id prolly just go ahead and run shearers. great pipe that should work well with that application. you might not give you as much on the bottom as cpi but youll have more on top. if you feel your bottom end is lacking with the shearers gear it down a little and youll still have a ton on top.

 

im not a fan of cpi in any way. i would never run them.

 

honestly on this setup id run the rockets. ive run them on a wide variety of motors and they perform well on all. problem is youll prolly never find a set of them.

There is a set of Rockets on ebay for $200. 4 hours left. Item number 110326658704.

Edited December 21, 2008 by spurdy

[brian]

id prolly just go ahead and run shearers. great pipe that should work well with that application. you might not give you as much on the bottom as cpi but youll have more on top. if you feel your bottom end is lacking with the shearers gear it down a little and youll still have a ton on top.

 

im not a fan of cpi in any way. i would never run them.

 

honestly on this setup id run the rockets. ive run them on a wide variety of motors and they perform well on all. problem is youll prolly never find a set of them.

 

Whats the gain of rockets over CPI ?

How do they compare to the Shearers ?

[RIPPEN]

Like most others have mentioned if your mostly duning and hill shooting I would say CPI's.. I have them on my 4mill duneport and they run great..

 

RIPPEN

[flotek]

ive traded rockets for shearer small bores o nseveral configurations and made more power with shearers even in lower rpms over the rockets surprisngly ,thats after extenisve jetting changes i found the jetting between the two was drasticly different. CPi is also an excellent choice for all around duner power and still retain good peak rpm numbers ,i prefer RDZ pipes for full drag though

[firebanshee]

I am a fan of fat bastards, but that is probably because i am one :biggrin:

[locogato11283]

Whats the gain of rockets over CPI ?

How do they compare to the Shearers ?

 

its all gonna depend on your motor setup. of course they will always be different. in my experience only, rockets made more power than the cpi on a motor that the builder claimed cpi would make the most. needless to say i stuck with my rockets. i also ran them on my 4mm cub with great success and even my 10mm cub.. i only recently switched to big bore shearers on my 10mm cub..

 

i dont like the look of the cpi. never have. that combined with my previous experience is why i pick rockets over cpi every time. but shearers for the big bore drag motors for sure.

[jbooker82]

Here are my spark arrestors for my CPI's. They are the trinity spark arrestors. You will have to mod them to make them fit.

 

The core hole needs to be drilled out from 1" to 1 1/8"

The three bolt holes that hold the end cap on wont line up so you ill need to re drill the 3 mounting holes.

 

Or you can do those ugly clamp on sparkies.

 

[wacko2000]

Here are my spark arrestors for my CPI's. They are the trinity spark arrestors. You will have to mod them to make them fit.

 

The core hole needs to be drilled out from 1" to 1 1/8"

The three bolt holes that hold the end cap on wont line up so you ill need to re drill the 3 mounting holes.

 

Or you can do those ugly clamp on sparkies.

 

 

Hey what does the spark arrestors do?

And DAMMMM who polished those silencers?

Those look awesome.