Anyone with experience with stock compression motors, what say you. Running straight AV gas, what is a "safe" boost limit of the stock motor, assuming good tuning, etc.
Nytro motor limits with stock compression
- Thread starter Wheel House Motorsports
- Start date
a couple riding buddies on stock motors were running 10psi on straight pump, it worked well and it left a good "buffer zone" if anything ever went south. as for good tuning if setup right with possibly a standalone setup 16lbs is not out of the question, gunners apex on here runs mid 20's stock compression on c16 or something like that with his standalone setup.
Stock compression you can run up to 17lbs as long as your octane is high enough. Personally I run 10 lbs on av fuel and can bump up to 15 if I run 110 in it.
Sent from my Commando
Sent from my Commando
After 17 lbs the rods may go, thus the limit on a stock motor.
Sent from my Commando
Sent from my Commando
hmm.. had one let a rod go at 11.5# on straight 100ll... at around 8k feet.... but it was pulling the weight of most people at 16-17#... that turbo setup made a LOT of power. built motor time!!
Hmm sounds like something else going on there, we got a supercharged nytro 10lbs pump gas running at 5000ft, 2000miles now and its using the dumb gems controller
R
robb
Active member
This is with no head shim ?
yup!
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Vi-PEC Powersports
Well-known member
No problem for 16 psi on stock compression on 91 octan pump gas at sea level ( with a standalone ) .
Vi-pec powersports
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08nytromtxa
Well-known member
Go tune your nytro for 500' at sea level and brag about your standalone somewhere else
V
Vi-PEC Powersports
Well-known member
with what kinda turbo kit. This is hard to believe, even with meth injection etc.
are you talking short run drag or actual riding ? julio
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08nytromtxa
Well-known member
Most people wouldn't run that much boost at sea level with a headshim and mixed fuel for any amount of time.. Except for him of course he's Probly put 1000's of miles on
i wouldnt
i wouldnt do it but i know you can get away with a lot in short bursts and not see problems that are coming. if you take a drag sled drop it in two feet of pow and bar it for two minutes you will most likely have a box of parts... julio
i wouldnt do it but i know you can get away with a lot in short bursts and not see problems that are coming. if you take a drag sled drop it in two feet of pow and bar it for two minutes you will most likely have a box of parts... julio
haha, yup! lived no problem tuning ripping around the field, first day in the hills on higher boost and she pooped a rod.
took it out for 3 rides at 8# working on tuning. first day on 11.5# she died.
strange part is how much weight we were pulling.
8BU's loaded to 72 grams, BWB spring, 45* helix and cat grean spring and almost on the rev limiter with a 174... usually thats what people are pulling at 16-17# it seems.
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Vi-PEC Powersports
Well-known member
rods and pistons are still in the bottom end.....sold the sled to a gentleman from alberta 2 years ago with 2900km, back to the origine prologger and dobex box, but this is the sled we first installed our standalone ecu on.Guys, we have snow too you know, and once you understand that elevation is being compensated and built in the fuel equation, then you won't be as skeptical.
T
Tarzannr1
Well-known member
I have run all Winter With 19,5 psi With my nytro mcx turbo with headshim and low comp pistions..
50/50 pumpfuel and avgas.
oh yea stock compression makes a huge difference, it took 7-8lbs more boost to pull the same clutching on my apex just dropping it to 10-1..
rods and pistons are still in the bottom end.....sold the sled to a gentleman from alberta 2 years ago with 2900km, back to the origine prologger and dobex box, but this is the sled we first installed our standalone ecu on.Guys, we have snow too you know, and once you understand that elevation is being compensated and built in the fuel equation, then you won't be as skeptical.
so this sled runs 16lbs at sea level no head shim stock compression, no meth, stock timing . just your tune, so low 20s for boost at elevation. is it your turbo set up? that thing should be a beast.. julio
I don't see any mention in here of what turbo you are running. A 2554 at 10 lbs no big deal but a big GTX or a 2871 or a 3071 or something totally different story. You need to do the CFM math.
M5
M5
