Blown engine?
Water injection is a must on our car. My last motor blew at 13 psi on a cool morning due to bad gas or contaminants in the oil injection. My used motor with 20,000 hard track miles has lasted 12,000 miles (and still going strong) running 14 psi and sometimes 17 psi with no problems (except for the fuel cut above 17 psi) with water injection. WI comes on at 7 psi and my knock # is always 25 or less. WI releases hydrogen and oxygen radicals that covers up uneven combustion and the heat absorbed from combustion also help tremendously. It works in hot or cold weather. I should have ran WI years ago.
And to boot, I have the rear iron bolt holes to the oil pan JB welded too. (but being a firm believer in Murphy's law, I have Howard Coleman rebuilt me a good engine from two bad ones so 0+0 does equal 1).
And to boot, I have the rear iron bolt holes to the oil pan JB welded too. (but being a firm believer in Murphy's law, I have Howard Coleman rebuilt me a good engine from two bad ones so 0+0 does equal 1).
Will definitely keep WI in mind for my next rebuild. I haven't lost any hope for the 13B yet... It just seems like nothing is overkill with these. I got into these knowing it was gonna cost me but I guess I still didn't prepare and overcompensate enough. Confidence is still high though, just money is low : (
Will definitely keep WI in mind for my next rebuild. I haven't lost any hope for the 13B yet... It just seems like nothing is overkill with these. I got into these knowing it was gonna cost me but I guess I still didn't prepare and overcompensate enough. Confidence is still high though, just money is low : (
Full Member
Joined: Mar 2011
Posts: 86
Likes: 1
From: Tampa
Water injection is a must on our car. My last motor blew at 13 psi on a cool morning due to bad gas or contaminants in the oil injection. My used motor with 20,000 hard track miles has lasted 12,000 miles (and still going strong) running 14 psi and sometimes 17 psi with no problems (except for the fuel cut above 17 psi) with water injection. WI comes on at 7 psi and my knock # is always 25 or less. WI releases hydrogen and oxygen radicals that covers up uneven combustion and the heat absorbed from combustion also help tremendously. It works in hot or cold weather. I should have ran WI years ago.
And to boot, I have the rear iron bolt holes to the oil pan JB welded too. (but being a firm believer in Murphy's law, I have Howard Coleman rebuilt me a good engine from two bad ones so 0+0 does equal 1).
And to boot, I have the rear iron bolt holes to the oil pan JB welded too. (but being a firm believer in Murphy's law, I have Howard Coleman rebuilt me a good engine from two bad ones so 0+0 does equal 1).
Granted I'm all for it but to say a must making only ~300hp? I think the power is very relevant too. Our combustion challenges seem to be in check with A/F up to around ~400whp, assuming you have the supporting mods. I mean am I off base here? I mean too me it seems like bad luck or a poor tune.
From my experience water injection is a nice to have below 16lbs on most setups on pump gas. I run 14lb on my twins @~330ish and now a t67 @380 stock port) with no issues for almost 10 years. Did the same before modding it too, purchased in 1996.
if having WI makes you sleep better at night then go for it.
seen just as many blow with auxiliary injection as without. auxiliary injection does help when pushing the car for extended periods of time where you might consider moving to race gas like at the track where ECT, EGT and IATs are getting up there. most people prefer it for raising boost levels beyond what pump fuel can accomodate for.
WI is not the fix all.
the reason most cars die in the dead of winter is due to boost creep pushing a car that was tuned in the dead of summer in stagnant hot air to the limits of the fuel system or stopping the mapping curve right at the edge of where the car was run to. a few additional PSI can be the matter of life and death of a motor if you do not compensate for the additional boost and fuel the engine needs.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
seen just as many blow with auxiliary injection as without. auxiliary injection does help when pushing the car for extended periods of time where you might consider moving to race gas like at the track where ECT, EGT and IATs are getting up there. most people prefer it for raising boost levels beyond what pump fuel can accomodate for.
WI is not the fix all.
the reason most cars die in the dead of winter is due to boost creep pushing a car that was tuned in the dead of summer in stagnant hot air to the limits of the fuel system or stopping the mapping curve right at the edge of where the car was run to. a few additional PSI can be the matter of life and death of a motor if you do not compensate for the additional boost and fuel the engine needs.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
Last edited by RotaryEvolution; Dec 10, 2011 at 04:24 PM.
Thanks for your input. This is exactly the kind of thing that keeps me confident about having the car. I come on here, ask some questions and I get real technical answers and solutions to help my build. Really appreciate it, thanks! 
if having WI makes you sleep better at night then go for it.
seen just as many blow with auxiliary injection as without. auxiliary injection does help when pushing the car for extended periods of time where you might consider moving to race gas like at the track where ECT, EGT and IATs are getting up there. most people prefer it for raising boost levels beyond what pump fuel can accomodate for.
WI is not the fix all.
the reason most cars die in the dead of winter is due to boost creep pushing a car that was tuned in the dead of summer in stagnant hot air to the limits of the fuel system or stopping the mapping curve right at the edge of where the car was run to. a few additional PSI can be the matter of life and death of a motor if you do not compensate for the additional boost and fuel the engine needs.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
seen just as many blow with auxiliary injection as without. auxiliary injection does help when pushing the car for extended periods of time where you might consider moving to race gas like at the track where ECT, EGT and IATs are getting up there. most people prefer it for raising boost levels beyond what pump fuel can accomodate for.
WI is not the fix all.
the reason most cars die in the dead of winter is due to boost creep pushing a car that was tuned in the dead of summer in stagnant hot air to the limits of the fuel system or stopping the mapping curve right at the edge of where the car was run to. a few additional PSI can be the matter of life and death of a motor if you do not compensate for the additional boost and fuel the engine needs.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
the reason most cars die in the dead of winter is due to boost creep pushing a car that was tuned in the dead of summer in stagnant hot air to the limits of the fuel system or stopping the mapping curve right at the edge of where the car was run to. a few additional PSI can be the matter of life and death of a motor if you do not compensate for the additional boost and fuel the engine needs.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
ideally you should tune the car in winter and have the tune checked in summer to be sure it is sufficient still. for example best safety measure is to tune a car to say 13-14psi during summer and is to run it at 11, maybe 12psi psi in summer. the creep in winter should cover the gap. also not a good idea to squeeze out that additional 5 horses to take the air fuel ratio to the bleeding edge.
another thing to consider is that not all dynos load the vehicle exactly like you will experience in the real world. so your AFRs may be off as soon as you unload the car from the dyno and take it on the highway doing the same things you were tuning it for on the dyno. this is where investing a few bucks into a wideband and gauge can and likely will save you thousands of dollars.
Great idea. I've noticed my car making more boost when the weather is cold (at least 2psi higher than usual, enough to trigger the EMS's overboost fuel cut).
I've also heard rumors that winter fuel blends are somehow 'not as good' as summer fuel blends. It would be interesting to hear specific differences, if there are any fuel experts willing to share that info.
it depends on the state and the alcohol content at various times of the year.
more alcohol means higher air fuel ratios(leaner burn), alcohol is less effected by freezing temperatures. almost all alcohol is less efficient than gasoline is(none that i know of match the energy content of gasoline but i'm not going to research it to be positive), even though alcohol is mixed with gasoline it is usually a very small % of the mix ratio so usually isn't going to greatly affect the tune unless it was mapped very aggressively and in conjunction with the additional boost from the denser cold air= a bad combination.
ethanol is about 35% less efficient when compared to gasoline. most pump gas has a peak level of 10% ethanol content.
for comparison sake i will use E85 as an example here. E85 is 85% ethanol content and 15% gasoline content which basically means it is an alcohol fuel. ~65% efficiency of gasoline if you had the car tuned to 11:1 AFR on pump gas(10% alcohol content) and pumped a tank full of E85 into the tank(85% alcohol content). you would have about a 30% leaner map. that is a 3.3 point AFR difference bumping the current tune of 11:1 AFR up to 14.4, definitely turning the motor to a brick if accidentally pumping the wrong gas into the tank.
anyways, that is the difference between a major change in alcohol content of the fuel, also why E85 vehicles need a much more stout fuel system to pump that additional 35% more fuel that the engine needs.
this isn't to scare anyone on pump fuel blends, but if your tune is set to a marginal level of 11.5:1AFR at 15+ PSI and even a 5% more alcohol content is introduced, that is enough to push it beyond safe. the difference would be almost .4:1 AFR pushing it close to 11.9:1 AFR which is definitely not a good target AFR for these engines at moderate to higher boost levels. most production vehicles can handle that disparity, an aggressively tuned rotary can't, especially if you had the "winterized fuel" run in the heat of summer.
the one benefit of the alcohol based fuels is that they have a higher octane rating which will suppress detonation somewhat at higher air fuel ratios.
more alcohol means higher air fuel ratios(leaner burn), alcohol is less effected by freezing temperatures. almost all alcohol is less efficient than gasoline is(none that i know of match the energy content of gasoline but i'm not going to research it to be positive), even though alcohol is mixed with gasoline it is usually a very small % of the mix ratio so usually isn't going to greatly affect the tune unless it was mapped very aggressively and in conjunction with the additional boost from the denser cold air= a bad combination.
ethanol is about 35% less efficient when compared to gasoline. most pump gas has a peak level of 10% ethanol content.
for comparison sake i will use E85 as an example here. E85 is 85% ethanol content and 15% gasoline content which basically means it is an alcohol fuel. ~65% efficiency of gasoline if you had the car tuned to 11:1 AFR on pump gas(10% alcohol content) and pumped a tank full of E85 into the tank(85% alcohol content). you would have about a 30% leaner map. that is a 3.3 point AFR difference bumping the current tune of 11:1 AFR up to 14.4, definitely turning the motor to a brick if accidentally pumping the wrong gas into the tank.
anyways, that is the difference between a major change in alcohol content of the fuel, also why E85 vehicles need a much more stout fuel system to pump that additional 35% more fuel that the engine needs.
this isn't to scare anyone on pump fuel blends, but if your tune is set to a marginal level of 11.5:1AFR at 15+ PSI and even a 5% more alcohol content is introduced, that is enough to push it beyond safe. the difference would be almost .4:1 AFR pushing it close to 11.9:1 AFR which is definitely not a good target AFR for these engines at moderate to higher boost levels. most production vehicles can handle that disparity, an aggressively tuned rotary can't, especially if you had the "winterized fuel" run in the heat of summer.
the one benefit of the alcohol based fuels is that they have a higher octane rating which will suppress detonation somewhat at higher air fuel ratios.
Last edited by RotaryEvolution; Dec 11, 2011 at 01:56 PM.
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