Meth Kit with CTSC

[cptnsx]

I think I've posted before but every since I've had my SOS intercooled supercharger I've logged my IAT for every drive. I have done some drag racing at the track (test and tune with multiple session in a row) but no road track sessions. I do live in Vegas and had driven very aggressive in 110+ heat with multiple back to back to back ....etc 60 - 120 blasts. The highest IAT I've ever seen is 210.

What I have seen is that the IAT sensor (which is mounted in a different location for intercooled cars) will heatsoak after only 5 to 10 min of driving to 35-40 degrees over ambient. This is with barely being on the throttle. After some moderate throttle play and continuous high rpm if ambient temp are high the heatsoak on the sensor can go as high at 50 degrees over ambient.

This is not the temp of the air entering the engine. I have done many back to back runs (in 100+ weather) where the starting temp is 135 and the end is around 185. If I do a run and then brake really hard keeping the throttle closed the IAT will rise to around 195-200 and if I get back on the throttle as the rpms drop to say 4K the IAT will read 195+ and then drop ....... and it will keeping dropping for about 2.5K rpm then stabilize (around say 175) then climb back to around 185 at 8K..... run after run.

If I look at my AF/R logs, I see my car getting leaner at those "elevated IAT temp readings" because my set-up compensates for temp. It pulls about 1.17% fuel for every 10 degree increase in temp. I start to lean out about .3 to .4 points because the air is not hotter but the sensor is heatsoaked and therefore sending the computer higher reading causing fuel to be pulled. Once the IAT stabilizes the AF/R is back to normal.

Since I never get much over 200 degrees I only see around 3 to 4 degrees of timing pull max and therefore only 15-20 less hp. I've slightly flatten my IAT to temp fuel modifier table since I rather be richer at higher temp then leaner ...... plus I was re-tuned to be around 11.3 to 11.5 vs. 11.8 and the sensor heatsoak was taken into account.

I'm still very fast in hot weather even back to back multiple runs (118 vs 121 in cold weather) and I stay in the 11 to 11.5 range.

I can't speak to track work since I'm waiting to get an oil cooler before I do that.

 

[Mac Attack]

Awesome! Thank you DynoMike and cptnsx!

Dave

 

[RYU]

Awesome! Thank you DynoMike and cptnsx!

Dave

+1

cptnsx - I just spent some time reading some of your old testimonials. Invaluable information. Thank you! I'm guessing you're running the Laminova and still seeing high AITs? Have you logged data before/after the intercooler install? Have you noticed the intercooler heat soak as well?

Mike - If one wanted to exhaust every possible AIT cooling solution while still using the CTSC fueling, in your opinion, are there any other options?

 

[cptnsx]

I did the intercooler with the SOS supercharger so no data without. I have heard that without an intercooler people were seeing 250+. The SOS intercooler kit comes with the AEM IAT. This IAT supposedly reads higher than stock (don't know how much).

It gets really hot here in Vegas and if you account for all this asphalt and no planet life who know what temps are at the filter before anything. I do know that in temps 70 and below I never get my IAT above 165ish.

Intercooler heatsoak seems to max around 200 degrees but only in hot weather.

 

[dynomike]

+1



Mike - If one wanted to exhaust every possible AIT cooling solution while still using the CTSC fueling, in your opinion, are there any other options?

please ask the question again not sure what you are asking

 

[TURBO2GO]

He is asking if you know of any options other than aftermarket engine management to cool AIT's.

He is trying to stay within the CARB certified standard CTSC fueling system. That's the reason of this whole thread.

I'm reading this with great interest.

 

[dynomike]

unfortunately there is no other forms of cooling AITs and still keeping it legal with crapifornia. Anything out of what Comptech has passed through CARB will not be legal. 9 out of 10 nsx that I dyno that have CTSC do not run correct AFRs. If the car has anything other stock exhaust and stock manifolds they almost always run on the lean side. The fortunate thing is that 99.9% of these cars are all street cars so they are never pushed and very rarely loose engines. What I am getting at is the CTSC is on the very edge to even being close to making the cars run correctly. Any form of trying to make the CTSC more efficient will definitively push them in to unsafe places with AFRs

 

[TURBO2GO]

Mike are you retaining CEL functionality with the EMS keeping the OBDII factory ECU?

Can you elaborate as to why you think Meth is giving you better results than an intercooler and what about all the concerns. What systems are you using and where are you injecting it.

And I am wondering... how would a car using this fail in CA?

 

[stuntman]

Short burst from 60-120mph and driving on a track where you're WOT (or should be) for longer than that without any time to cool down is two completely different things. The relentless lack of 'cooldown' time lap after lap tests cooling systems where they will reach an equilibrium. From my experience, even inter/aftercooled cars can see 250*+ on track.

I am currently setting a nsx up with methanol injection and CTSC autorotor as we speak. I am running this car on the brand new series 2 AEM EMS that I have converted to run on the nsx. I have sprayed methanol through blowers for years and not have had any ill effects. In order to take full advantage of methanol injection you do have to have the ability to tune for it. I would be hesitant to put methanol injection on a standard CTSC using the stock computer. The way the stock computer pulls timing is with high IAT. the methanol has such a good cooling effect that your iats are some times less than ambient temperature. I would be afraid of detonating the engine with the stock computer because there would be no timing retard done due to low IATS. In my opinion methanol injection for the CTSC nsx in the best way of cooling the air charge. The inter coolers that are on the market do work but I feel that methanol injection works better

Detonation from no timing retard done due to low IATs?

I can't imagine IATs being below ambient unless the SC was relatively cool from daily driving to begin with, after a few hard pulls and especially on track its hard enough keeping IATs within 80* of ambient.

 

[GCNSX]

unfortunately there is no other forms of cooling AITs and still keeping it legal with crapifornia. Anything out of what Comptech has passed through CARB will not be legal. 9 out of 10 nsx that I dyno that have CTSC do not run correct AFRs. If the car has anything other stock exhaust and stock manifolds they almost always run on the lean side. The fortunate thing is that 99.9% of these cars are all street cars so they are never pushed and very rarely loose engines. What I am getting at is the CTSC is on the very edge to even being close to making the cars run correctly. Any form of trying to make the CTSC more efficient will definitively push them in to unsafe places with AFRs

Are there any meaningful adjustments that can be made on the FPR in a whipple kit? My car has what was probably one of the last whipple kits, it was installed new in 2006. When I hear 9 out of 10 of these kits run too lean that concerns me. Mine is a 3.2L low boost with CT headers, OEM cats, and GTLW exhaust. I plan to dyno in the next couple weeks and monitor A/F. If there are adjustments I can make, I'd like to know to keep it as safe as possible.

I agree with what is being said here. I love the power of my car before it gets too hot. On a cold morning it's a rocket (to me). If I can do something as simple as water/meth injection and keep that power even as things heat up, I'd be all over it, but I am not interested in blowing up an engine to get there. If I am going to go to the high boost setup and add an intercooler, financially it makes more sense to sell what I have and get a good turbo kit. The cost differential at that level is not very much in the overall scheme of things.

 

[stuntman]

Are there any meaningful adjustments that can be made on the FPR in a whipple kit? My car has what was probably one of the last whipple kits, it was installed new in 2006. When I hear 9 out of 10 of these kits run too lean that concerns me. Mine is a 3.2L low boost with CT headers, OEM cats, and GTLW exhaust. I plan to dyno in the next couple weeks and monitor A/F. If there are adjustments I can make, I'd like to know to keep it as safe as possible.

I agree with what is being said here. I love the power of my car before it gets too hot. On a cold morning it's a rocket (to me). If I can do something as simple as water/meth injection and keep that power even as things heat up, I'd be all over it, but I am not interested in blowing up an engine to get there. If I am going to go to the high boost setup and add an intercooler, financially it makes more sense to sell what I have and get a good turbo kit. The cost differential at that level is not very much in the overall scheme of things.

Not much will really get you to making the same power as when the AITs are in the 60s or 70s but efficiently keeping them around 130 or below in a daily and sub 180 on track is far better and will prevent a huge loss in power than 150s and 250s respectively.

 

[dynomike]

Short burst from 60-120mph and driving on a track where you're WOT (or should be) for longer than that without any time to cool down is two completely different things. The relentless lack of 'cooldown' time lap after lap tests cooling systems where they will reach an equilibrium. From my experience, even inter/aftercooled cars can see 250*+ on track.

Detonation from no timing retard done due to low IATs?

I can't imagine IATs being below ambient unless the SC was relatively cool from daily driving to begin with, after a few hard pulls and especially on track its hard enough keeping IATs within 80* of ambient.

billy I am sure you have had brake cleaner sprayed on your hand before it is really cold. Methanol is very similar. when we are on the dyno making back to back loading and runs the intake where the methanol is injected will actually start to condensate from being so cold. depending on circumstances I have seen IAT go below ambient while on the dyno. Just depends how much boost your putting out. I will post some logs next week of this car and what it does.

as for detonation due to low IATs I was referring to when the nsx runs the stock computer. the stock computer pulls timing when IATs are high. if you cool iats down you effectively loose your timing retard for the supercharger

 

[RYU]

billy I am sure you have had brake cleaner sprayed on your hand before it is really cold. Methanol is very similar. when we are on the dyno making back to back loading and runs the intake where the methanol is injected will actually start to condensate from being so cold. depending on circumstances I have seen IAT go below ambient while on the dyno. Just depends how much boost your putting out. I will post some logs next week of this car and what it does.

as for detonation due to low IATs I was referring to when the nsx runs the stock computer. the stock computer pulls timing when IATs are high. if you cool iats down you effectively loose your timing retard for the supercharger

Mike, Is there anyway to spray the meth/water in such a small quantity (10% as Dave said?) in which it will cool down the charge temps but not over cool it? Is there a way to control that?

All we're trying to do is get it down from 250 to say.. 150-180. Maybe it can't be boost dependent all of the time but perhaps the system only comes online via above a certain AIT threshold.

 

[stuntman]

billy I am sure you have had brake cleaner sprayed on your hand before it is really cold. Methanol is very similar. when we are on the dyno making back to back loading and runs the intake where the methanol is injected will actually start to condensate from being so cold. depending on circumstances I have seen IAT go below ambient while on the dyno. Just depends how much boost your putting out. I will post some logs next week of this car and what it does.

as for detonation due to low IATs I was referring to when the nsx runs the stock computer. the stock computer pulls timing when IATs are high. if you cool iats down you effectively loose your timing retard for the supercharger

What's your dyno method? Do you warm up the engine and trans with pulls (how many) and them make your consecutive pulls or do you do it as soon as the motor idles to temp and then let it cool down?

I believe AITs below ambient but not on a hot motor. Keep us posted!

Wouldn't the stock ecu retard timing with high AITs and start to advance them again as the AITs drop?

 

[dynomike]

Wouldn't the stock ecu retard timing with high AITs and start to advance them again as the AITs drop?

That is correct. With out the high Iats the stock computer would give full timing to the engine forcing it to detonate under boost. It doesn't matter how hot the engine is with methanol. When it is injected into the intake track it instantly mixes with the air going into the engine rapidly cooling it.

 

[stuntman]

That is correct. With out the high Iats the stock computer would give full timing to the engine forcing it to detonate under boost. It doesn't matter how hot the engine is with methanol. When it is injected into the intake track it instantly mixes with the air going into the engine rapidly cooling it.

I'm trying to follow the first two sentences.. Without high IATs (normal driving) timing is at its proper settings, as the IATs increase, the stock ecu compensates by pulling/retarding the timeing but also with very low IATs it will advance timing, no?

I guess it depends on where the meth injection and manifold air temp sensor is located, at about static pressure or post SC under pressure and extreme heat after prolonged heavy loading. If both are post SC I doubt it the meth will ever bring it even to ambient.

 

[dynomike]

you want to put the meth pre SC so that the meth has time to atomize with the air and also to go through the SC to cool everything down. The air temp sensor is located post SC

 

[RYU]

Mike, Is there anyway to spray the meth/water in such a small quantity (10% as Dave said?) in which it will cool down the charge temps but not over cool it? Is there a way to control that?

All we're trying to do is get it down from 250 to say.. 150-180. Maybe it can't be boost dependent all of the time but perhaps the system only comes online via above a certain AIT threshold.

Mike, sorry.. so going back to my question is there a way to control the spray for the purposes of cooling AITs? Is that something you can think of a possible solution for perhaps?

Is it more advisable to use 100% water or maybe a 30/70 meth/water mix?

 

[Caustic]

Please forgive my ignorance, I'm trying to learn as much as possible about this, but something said about cooling and advancing timing confused me.

Let me start by defining the engine setup: typical CT-Engineering set and forget low boost 1.7 Autorotor/1.6 Lysholm on a stock motor. There is water/meth injection pre-SC, and the intake temps are measured post-SC.

Correct me if I'm wrong:
Generally, isn't this a good thing? If intake temps are too high, the ECU retards timing, then the car loses power. The injection will help to lower temps.

If the intake temps drop low because of the water/meth injection, why is this a bad thing? Isn't this the same as driving your NSX in cold weather? Doesn't the ECU see this and adjust accordingly? Not sure how low it could really be post-SC.

Since the water/meth injection is the only thing outside the typical low boost CT-Engineering SC in the above setup, shouldn't we manage the injection, then let the SC do its thing? For instance, making the water/meth inject according to intake temp, maintaining a relatively constant 150 degree temp (post-SC as per the sensor). The SC and engine doesn't have to know whats going on. All they know is the temps are around 150 degrees.

dynomike says:

...9 out of 10 nsx that I dyno that have CTSC do not run correct AFRs. If the car has anything other stock exhaust and stock manifolds they almost always run on the lean side. The fortunate thing is that 99.9% of these cars are all street cars so they are never pushed and very rarely loose engines. What I am getting at is the CTSC is on the very edge to even being close to making the cars run correctly. Any form of trying to make the CTSC more efficient will definitively push them in to unsafe places with AFRs

Can this be confirmed, cause that is is scary for those that push their cars with a CTSC.

I think this is what the others are asking, mainly because I've been asking myself the same questions for a few months now. Where does my logic fail, or what information am I missing? I know I must be overlooking something.

 

[stuntman]

Please forgive my ignorance, I'm trying to learn as much as possible about this, but something said about cooling and advancing timing confused me.

Let me start by defining the engine setup: typical CT-Engineering set and forget low boost 1.7 Autorotor/1.6 Lysholm on a stock motor. There is water/meth injection pre-SC, and the intake temps are measured post-SC.

Correct me if I'm wrong:
Generally, isn't this a good thing? If intake temps are too high, the ECU retards timing, then the car loses power. The injection will help to lower temps.

If the intake temps drop low because of the water/meth injection, why is this a bad thing? Isn't this the same as driving your NSX in cold weather? Doesn't the ECU see this and adjust accordingly? Not sure how low it could really be post-SC.

Since the water/meth injection is the only thing outside the typical low boost CT-Engineering SC in the above setup, shouldn't we manage the injection, then let the SC do its thing? For instance, making the water/meth inject according to intake temp, maintaining a relatively constant 150 degree temp (post-SC as per the sensor). The SC and engine doesn't have to know whats going on. All they know is the temps are around 150 degrees.

dynomike says:

Can this be confirmed, cause that is is scary for those that push their cars with a CTSC.

I think this is what the others are asking, mainly because I've been asking myself the same questions for a few months now. Where does my logic fail, or what information am I missing? I know I must be overlooking something.

I agree with everything you have said.

you want to but the meth pre SC so that the meth has time to atomize with the air and also to go through the SC to cool everything down. The air temp sensor is located post SC

I'm not experienced meth but as Caustic has said, either way having the sensor post SC is a good thing; and IMO (not from experience though) I have a hard time believing the AITs (measured post-charger) will be below ambient or even close to ambient during track use or even on a hot day for prolonged street runs.


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[Caustic]

Mike, sorry.. so going back to my question is there a way to control the spray for the purposes of cooling AITs? Is that something you can think of a possible solution for perhaps?

Is it more advisable to use 100% water or maybe a 30/70 meth/water mix?

The Stage 2 version of the kit that BATMANs linked allows you to map injection flow rate according to AIT. It seems pretty straightforward and exactly what you are looking for.

I think what you want to do is possible.

BTW:

1. RYU has exceeded their stored private messages quota and cannot accept further messages until they clear some space.

:tongue:

 

[cptnsx]

The problem is the IAT sensor is in the intake manifold (either stock for non-intercooled cars or the custom intake manifold for intercooled cars). Either way the sensor itself heat soaks. When I was bleeding my coolant about a billion times last year, the IAT sensor after just 15-20 min of idling would be 20-35 over ambient. Is the air really that much hotter ....... no. The air traveling through the intake tract just does not have that much time to pick up all that heat esp at 100+ (unless you have an open filter in the engine bay) but that sensor is just sitting there soaking up that heat. Just a thought.

The problem with the cool or cold temp or cooler IATs with the stock comptech supercharger is that the stock comptech supercharger uses the stock timing. Anyone who has a tuned AEM on the comptech or SOS supercharger (if they look) can see the timing has been adjusted (and its not higher). I have never gotten a right answer about just what the stock timing on a NSX is but I believe the speculation is WOT max is some where around 28-32 degrees. And like it was stated earlier does the stock ecu add timing if the IATs are really low?

 

[RYU]

I appreciate everyone's patience and feedback while this newbie learns... I still feel like i'm missing something.

cptnsx - thanks for that feedback on the OEM sensor heatsoaking. I did see that on a previous post you had that same concern. If the factory ECU adds timing when cold I see that as a problem too but that's only if the AIT is cooled too much, right? Again, if an AEM EMS was an option this entire thread is moot so I get that too.

Here's how I see things. I would have to assume that Comptech performed this tune on back to back dyno runs.. but perhaps not back to back to back to back to back dyno runs when the SC would significantly heat soak (big assumption on my part). I think it's safe to assume though that the factory ECU does retard timing when IATs are hot or else there'd be more blown motors out there. However, when the car does an initial WOT run, while still cool, it has to be at a safe AFR while still on unretarded timing. Let's also say the AIT, on a non-intercooled stock low boost CTSC, only gets up to 190-200degs at 60 degs ambient at the end of the same 1-3rd gear pull. However, in first/second gear on the first pull it's likely at only 30-50 over ambient since it hasn't had time to heat soak yet. Why can't the meth mimic the conditions to constantly keep the factory ECU thinking it's always at 30-50 over ambient before it needs to pull back the timing? Essentially, one could use the meth/water spray in small amounts to mimic that it's only 60 degs outside and AITs are always at 30-50 over? If it's running under early morning, 1st run of the day conditions, why would the timing be advanced?

On a different note, if the factory AIT sensor heat soaks because of other reasons, which is unfortunate, have you found a better location to place a different aftermarket AIT sensor that will accurately read AITs?

Is anyone out there using an aftercooler with the stock low boost CTSC? Since that thing is "always on" effectively this problem of initially overcooling AITs would have been experienced me thinks...

 

[cptnsx]

The problem is that the Comptech solution counts on the heat soak. I think most of it is sensor heat soak but that is irrelevant. It could be sensor or real heat soak, Comptech counts on it and therefore they know when the car comes up to temp you are going to get retarded timing.

The Comptech solution has zero timing retard explicitly. So if you keep the IAT lower (than Comptech planned for) the stock computer will not pull timing and you could be in trouble. In very cold weather the autorotors were having knock issues. They were minor because the temps were very cold (this happened in winter time). Second according to dynomike the AF/R is already borderline (too lean) so with some meth spray you will get colder IAT but no timing pull (so full stock timing) and you will be even leaner. This is a bad combo.

 

[stuntman]

The problem is the IAT sensor is in the intake manifold (either stock for non-intercooled cars or the custom intake manifold for intercooled cars). Either way the sensor itself heat soaks. When I was bleeding my coolant about a billion times last year, the IAT sensor after just 15-20 min of idling would be 20-35 over ambient. Is the air really that much hotter ....... no. The air traveling through the intake tract just does not have that much time to pick up all that heat esp at 100+ (unless you have an open filter in the engine bay) but that sensor is just sitting there soaking up that heat. Just a thought.

I'm not so sure I would write off the sensor's accuracy due to heat soak just that easily.

When your car was idling, I assume your engine was up to temp and yes the intake manifold heat soaks through convection, radiant, and conduction, and when idling with the throttle body basically closed, the hot intake manifold heats the air inside the manifold where the sensor is reading. I would be interested in the IATs after a few blips of the throttle, getting more air flow through the intake manifold which I would bet would see a drop in IATs due to the relatively cooler air than at idle.

Now on track or heavy use, the stock intake manifold does get very hot through the above methods -and this DOES transmit to increasing the IATs. This is why many intake manifolds in racecars use carbon fiber which dosn't conduct heat as well, and then they go to lengths to reduce radiant heat further by use of reflective heat shielding. Our stock cast manifolds are terrible by comparison. Throw a supercharger on top of it, which superheats the air as it compresses it, superheating the intake manifold further, along with other factors, and your IATs are through the roof.

I think the higher than ambient temps you're noticing are accurate and i'm sure you'll see a drop in these temps by taking measures to isolate the manifold from heat -a main goal of many race teams.

Here's how I see things. I would have to assume that Comptech performed this tune on back to back dyno runs.. but perhaps not back to back to back to back to back dyno runs when the SC would significantly heat soak (big assumption on my part). I think it's safe to assume though that the factory ECU does retard timing when IATs are hot or else there'd be more blown motors out there. However, when the car does an initial WOT run, while still cool, it has to be at a safe AFR while still on unretarded timing. Let's also say the AIT, on a non-intercooled stock low boost CTSC, only gets up to 190-200degs at 60 degs ambient at the end of the same 1-3rd gear pull. However, in first/second gear on the first pull it's likely at only 30-50 over ambient since it hasn't had time to heat soak yet. Why can't the meth mimic the conditions to constantly keep the factory ECU thinking it's always at 30-50 over ambient before it needs to pull back the timing? Essentially, one could use the meth/water spray in small amounts to mimic that it's only 60 degs outside and AITs are always at 30-50 over? If it's running under early morning, 1st run of the day conditions, why would the timing be advanced?

On a different note, if the factory AIT sensor heat soaks because of other reasons, which is unfortunate, have you found a better location to place a different aftermarket AIT sensor that will accurately read AITs?

Also keep in mind that a 1-3 gear pull is fine, but on track, you have a 2-4 (brake) 3-4 (brake) 2-5 (brake) 2-3 (brake) 3-4 etc... - each lap and never stops. The problem and temps will raise to a usually very high equilibrium.

Until objective proof from proper testing is done, I think the factory AIT sensor and location is fine and is doing its job properly. The IAT's SHOULD be higher than ambient. Every NA car's IATs are above ambient, if you race, you try to lower those IATs through heat shielding. A better test would be to measure IATs when cruising on the freeway.

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