racinstation
Extreme
We have always used low compression pistons, Carillo rods, and or a head shim along with cam timing at high boost levels (15 plus). How much boost have you guys run with a completely stock motor? At what boost and also what octane and elevation? Just trying to acquire some information for a build. Any input is appreciated.


mulot30th
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apex mountain crracing 174
apex blower 136 for asphalt racing
osp drag race sled (apex engine based)
its not boost as much as hp/tq and NO DETO that count with stock internals.
I have in my MCX 180 kit in my Nytro 6 psi
Tarzan
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well.. i have run 21 psi in dyno stock engine and run now 19 psi on stock engine on Ethanol mixture.
Cant say i am safe so i will turn it down to 17 psi.
Cant say i am safe so i will turn it down to 17 psi.
I ran 18lbs on 100% stock apex motor. Ran 22-24lbs on same motor with head shim to lower compression.
I think Jannetty runs 25 plus on completely stock RX-1
just with Retorque on the head studs.
Its all about good fuel and not heat soaking the engine.
I think Jannetty runs 25 plus on completely stock RX-1
just with Retorque on the head studs.
Its all about good fuel and not heat soaking the engine.
zx670
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Ive been running 16-18 for the last 3 years on mine with a never been opened stock engine on av gas, but i also ride at 10,000ft so there is about 5psi less atmospheric pressure to start with up there
quebecmoutainrider
TY 4 Stroke Junkie
sealevel-14psi on 92 and 19psi on 110..was told I could run 94 octain at 19psi..not going to try..lol.


mulot30th
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apex mountain crracing 174
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osp drag race sled (apex engine based)
quebecmoutainrider said:sealevel-14psi on 92 and 19psi on 110..was told I could run 94 octain at 19psi..not going to try..lol.
what head shim thickness?
19 psi pump gaz sounds crazy.
TurboTime
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I've talked with a few guys on this very topic; OSP and Smith Racing. For the Nytro the engine is able run 8-10lb of boost with 93 and up to 15-16lbs with C14 - C16 race fuel
Sea level stock motor no shim...
My take its really depends on the detno and how long you WOT in specific conditions..
Hope this helps..
KI
Sea level stock motor no shim...
My take its really depends on the detno and how long you WOT in specific conditions..
Hope this helps..
KI
quebecmoutainrider
TY 4 Stroke Junkie
You would have to ask the guys at G-Force..but I think its 10 mil.they didnt say pump.they told me 110 at 18 but its at 19.and that I could run 92-94 at 13 but its 14..There are guys running high numbers and they have had no problems..I even have a warrior rad on the back to help get rid of the extra heat.And have been told to always check the A\F after I fill it..never know if the fuel is really what they say you are buying.The sled was sappose to be 13-18psi..but it always says 14 or when up high 19 on race.

FLYBYU
VIP Member
On a stock motor IMO would not take it over 8 unless I was using 116 max nos fuel.quebecmoutainrider said:You would have to ask the guys at G-Force..but I think its 10 mil.they didnt say pump.they told me 110 at 18 but its at 19.and that I could run 92-94 at 13 but its 14..There are guys running high numbers and they have had no problems..I even have a warrior rad on the back to help get rid of the extra heat.And have been told to always check the A\F after I fill it..never know if the fuel is really what they say you are buying.The sled was sappose to be 13-18psi..but it always says 14 or when up high 19 on race.
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