11.1:1 + 6psi = x

[TrunkMonkey]

id say try it, because you have spare shortblocks? laying around...but i cant think of it right off the top of my head but as far as science and math go, whats the compression going to be on the rotating mass of the pistons, ring lands and rods at 6psi on 11.0:1 compression, id say if it is close enough to 8.5:1 or 9.0:1 at 12-15psi youll be fine, and could in theory use the same fuel setup as a car with 9.0:1 compression at 15psi.....but thats only if the numbers line up......as a precaution id say run the numbers( if you can find the equation) just to be safe....and then that would give you a good starting point...

and just tie the whole point together.... your starting compression + whatever PSI your running on turbo = much higher compression on rotating mass.... and people may have already known this...im just clearing things up

i've been too lazy to crunch any numbers...maybe later tonight.

-demetrius

[CoolBlue]

Theoritically you will make more horsepower per pound of boost with the higher compression. Also, what do you want. You can look at it 2 ways. "im running 15 lbs of boost to make x amount of horsepower", or "im making x amount of horsepower with 7 lbs (due to higher compression". Is your goal a boost # or a horsepower#?

It's something that would need to be experimented with, since the tuning strategies for 11:1 and the stock cr will be different (less timing, more fuel). It's trying to determine if the less timing+ more fuel+higher cr is better then the stock cr and basically what everyone is running right now. Also, as mentioned, detonation will be much more likely to have a party on your pistons at higher cr's with pump gas.

It's a tradeoff really, and one that isn't explored I don't think. Does a KA with a higher CR with less boost make more power then a KA with stock or less then stock CR at a lower boost.

Just my .02

[WDRacing]

You'll make more power raising boost and lowerring CR, simply because of octane problems. But demcj seems determined to go a different direction. Which isn't a bad thing.

If JWT can tune your ecu with some good timing maps for boost and a high CR I think you'll be in bussiness. Ignition will be the hard part of the tuning I think, adding fuel is easy enough.

I'd like to suggest the J&S Knock system. That will increase the safety margine alot. Atleast use a MSD knock meter or similer. Who knows, if things work out good, maybe we can start playing around with better pistons and some alternative fueling for some higher boost, could be fun.

WD

[ca240]

two things...what is swain coating? and why the to4e, why not a t3/t4 since you dont seem like you think you'll be gettin over 300hp to start with? it would just spool faster and make this project that much cooler...my 2 cents

[andrave]

yeah I've noticed that cars running higher CR always seem to be running larger than normal injectors too. swain coating is a heat coating that can make something dissipate heat faster. They have a variety of coatings available, such as ones that reduce friction, or other neat stuff. Not cheap though...

[TrunkMonkey]

two things...what is swain coating?

swain

and why the to4e, why not a t3/t4 since you dont seem like you think you'll be gettin over 300hp to start with? it would just spool faster and make this project that much cooler...my 2 cents

the larger turbine will help keep temps cooler. besides, i don't care for a fast spool up. if it spools up by 4k rpms, i'm happy. i like being able to drive off boost.

and to quote someone from another forum..."lag is just a polite way of giving your opponent a head start."

-demetrius

[3rD GeAr]

i think this project is something different but i would recommend aftermarket forged pistons. but if u decide to stay with the stockers just make sure a/f ratios are real good. good luck Nikocheck out my sig:D

[SingleCamSam]

Don't higher compression engines have lower BSFC? I think this is why people running 370cc injectors have been able to get more power out of the KA than would normally be obtainable. Like WD said i think timing is going to be your biggest concern.

..."lag is just a polite way of giving your opponent a head start."

hehe, i gotta write that one down!

[k6kicker]

that would spool like a mofo, high compression and and a long stroke...drooooooooooooooooooooooooool

[huguetpj]

..."lag is just a polite way of giving your opponent a head start."

hehe, i gotta write that one down!

Once I get my KAT to purrrrr there are two stickers that I'll definetely having made:

1. "Gone V8 hunting... be back in X seconds"2. Either "Lag is a polite way of giving V8s a head start" or "KAT got your tongue" (ADAMHU)

[NateDogg]

WDRacing makes a good point about the J&S or if you want something cheaper get the MSD knock-alert.

The Honda guys are in a bit of a different situation because their combustion chambers have more quench hence more resistance to detonation.

I think 9.5:1 on pump gas is hard enough when boosted. For every point increase in compression, you gain 2-3% power. So you're making about ~5% more power for a whole lot of headache.

[TrunkMonkey]

WDRacing makes a good point about the J&S or if you want something cheaper get the MSD knock-alert.

the j&s is very nice indeed, but the msd is out of the question. i'd like something that does more than just detect detonation.

The Honda guys are in a bit of a different situation because their combustion chambers have more quench hence more resistance to detonation.

honda isn't the only engine that being boosted with high compression. vw, bmw, nissan/infiniti, toyota...the list is about as long as the list of car manufacturers on the market.

I think 9.5:1 on pump gas is hard enough when boosted. For every point increase in compression, you gain 2-3% power. So you're making about ~5% more power for a whole lot of headache.

the formula holds true for n/a applications, but not so when boosted. proof taken from a reliable source on another forum...

originally posted by Greaseryep, thats the basic idea. Higher compression raises your power/torque everywhere in the power band. lower compression will lower it but allow more "boost" or air and fuel to be "stuffed" into the combustion chamber than a higher compression motor would. (but whats funny is the higher compression motor is funner to drive and on some ocasions actually makes the same power or more at lower boost.

example2000 honda civic SI. with a bolt on turbo kit at 7psi the car put down 244. He rebuilt with 8:1 pistons for a drop in 2.? points of compression. he put down 243@12psi HAHAHAHAAHAHAHAH lol. needless to say, hes back up to 11:1 with turbo and putting down 420fwhp @18psi on a 1.6 DOHC VTEC motor.

if you want to read the entire discussion...

i finally got around to crunching some numbers (i cheated and used a couple of calculators on the net). from what i've gathered, 6 psi at 11.1:1 compression is about the same as running 10 psi on 9.5:1.

should be a piece of cake .

-demetrius

[klattr1]

but i think you would make more power out of your motor with 10 psi on 9.5:1 compression ratio versus 11.1:1 at only 6 psi.Its just the nature of boost.

[Projex240]

There are way too many factors here that demcj is forgetting when he talks.

1) The honda motors you are referring to that are boosted with aftermarket turbo kits are making only minimal power, and can almost never be turned up in boost in bolt on form. 2) honda motors have forged internals The b16a block, i dont car what is said, will NOT stand up to 400+ hp without a built bottom end...you are talking about using stock internalson your project...two totally different animals here.3)a bigger turbine will keep things cooler, but most likely be nowhere near a good efficiency range- thats just bad engineering if you use a bigger turbine to compensate for one problem, but sacrifice efficeincy, thus creating another problem.4)ringlands---everyone knows this...i dont need to go into it. If you tune your car with a certain tank of gas, or a good air temp, or a good atmospheric pressure, you will have a good running car. However, when you go out in the streets and are running around in 100 degree heat (im from columbia..i know about sc heat/humidity), you will detonate, and all it takes is once or twice to kiss those lands goodbye. If you get a bad tank of gas....peace out ringlands. Then you got a rebuilt blowed up project car that doesnt run. All for a smidge over 200 hp.5) You cannot compare non-turbo cars built to be turbo cars, with cars that were turbocharged from the factory. Factory turbo cars use a much less aggresive computer program for timing than even JWT. They pull timing for anything...even air intkae temp. JWT doesnt provide for that tha same say mitsu or audi does. Thos cars also come with beefy factory internals. once again- two totally different animals here. 6) 11:1 on 6 lbs is not the same as 9.5:1 on 10 lbs. Boost is not determined simply by lbs. But by heat range, egt, efficeincy, etc...that 11:1 is going to raise egt's a bit and cause tuning to be slightly more difficult than conventional means.If you go this route, you will have to retard timing so much you will lose the low end off boost driveability that you are looking forward to. 9.5 to one is a good ratio for low boost due to the fact it is great for pump gas, and boost timing maps. If you tear open a motor for 11:1 build up...dont be dissapointed when you have to limit yourself to never upping boost. YOu may yeiala round 225 or so. But for the time money aggrevation, and risk...and that low of power...why even try it? I completely agree with wanting to be different. But there are better more logical avenues.

[Projex240]

Just so ya know though....I do think that higher than 9:1 with boost is cool as hell. But it has to be done right. Using weak assed factory internals with 11:1 with a plug and play JWT and an afc is outright dumb, even for low boost/power. Forged internals with a standalone is the only way id throw money into a project like that.but hey...its your dough.Just for ****s and giggles...lets go through this.Motor parts:Pistons - about 150 if they are cheapmore so around 250-300 if you want a good set or new.Machine work and rebuild-1000...if its less...watch out unless youll do it yourself.JWT ecu - 550 from stillen--call phil tell him i said wattup.afc 2- 330 afc is just as good for about 260 but doesnt have a much fine-tunability.turbo--do it cheap 1700 with good parts and cutting corners. but more likely about 2500 for a good kit.clutch to take the power - 300better run an external wastegate- you cant afford to have ANY boost creep- low boost on big turbos means creepy boost is out for you!!!!250gauges and a techtom for monitoring a knock- around 300so roughly(very roughly)5600 bucks----for 225+/- ?! Its just not worth it bro.Be different and put a 2jz in it or something like that, but dont just waste money.

[SingleCamSam]

So how is it that RSX-S owners are making up to 300whp on stock bottom end if what you said is true? I don't think the K20 has forged internals. I agree it's alot of trouble but i don't think it will be as hard as you make it sound.

[TrunkMonkey]

There are way too many factors here that demcj is forgetting when he talks.

let's go over these.

1) The honda motors you are referring to that are boosted with aftermarket turbo kits are making only minimal power, and can almost never be turned up in boost in bolt on form.

not true.

2) honda motors have forged internals The b16a block, i dont car what is said, will NOT stand up to 400+ hp without a built bottom end...you are talking about using stock internalson your project...two totally different animals here.

i'm assumming that you meant that honda engines do not have forged internals? no one said anything about a stock block b16a being able to hold up to 400+ hp. the point of the reference was to show what type of effect compression ratio has on boost.

3)a bigger turbine will keep things cooler, but most likely be nowhere near a good efficiency range- thats just bad engineering if you use a bigger turbine to compensate for one problem, but sacrifice efficeincy, thus creating another problem.

do some research. the t04e 60 trim is more efficient than almost any of the turbos being run on this forum. this is the turbo i planned on using regardless of the compression ratio. a larger turbine doesn't automatically mean inefficiency. 4)ringlands---everyone knows this...i dont need to go into it. If you tune your car with a certain tank of gas, or a good air temp, or a good atmospheric pressure, you will have a good running car. However, when you go out in the streets and are running around in 100 degree heat (im from columbia..i know about sc heat/humidity), you will detonate, and all it takes is once or twice to kiss those lands goodbye. If you get a bad tank of gas....peace out ringlands. Then you got a rebuilt blowed up project car that doesnt run. All for a smidge over 200 hp.

i'm kinda getting tired of people preaching about weak ringlands. while it isn't a subject i ignore, seeing proof of several 300+ hp daily driven stock bottom end KAs last for 2+ years is enough for me not to sweat the ringlands. the longest surviving being brutalized on severe daily/track/drifting use at 14psi on 91 octane with a "crappy" jwt ecu...and he's been doing it for a little over 4 yrs now...in the arizona heat.

5) You cannot compare non-turbo cars built to be turbo cars, with cars that were turbocharged from the factory. Factory turbo cars use a much less aggresive computer program for timing than even JWT. They pull timing for anything...even air intkae temp. JWT doesnt provide for that tha same say mitsu or audi does. Thos cars also come with beefy factory internals. once again- two totally different animals here.

who's comparing n/a and turbo cars? every car that i may have mentioned came n/a from the factory, and have had aftermarket kits strapped to them.

6) 11:1 on 6 lbs is not the same as 9.5:1 on 10 lbs. Boost is not determined simply by lbs. But by heat range, egt, efficiency, etc...that 11:1 is going to raise egt's a bit and cause tuning to be slightly more difficult than conventional means.

6 psi on 11.1:1 has about the same final compression ratio (boost/effective compression) as 10 psi at 9.5:1. so yes, all the conditions you've listed should be about the same.

If you go this route, you will have to retard timing so much you will lose the low end off boost driveability that you are looking forward to. 9.5 to one is a good ratio for low boost due to the fact it is great for pump gas, and boost timing maps. If you tear open a motor for 11:1 build up...dont be dissapointed when you have to limit yourself to never upping boost. YOu may yeiala round 225 or so. But for the time money aggrevation, and risk...and that low of power...why even try it?

really, some of you are making this a bigger beast than what it actually is. keep in mind, i don't intend to run insane amounts of boost, nor am i trying to make big hp numbers. from everything i've gathered, i'm not pushing the envelop any farther than what's already been proven. i'm just taking a different route. it'll all come down to tuning.

...only 225 hp? i was thinking more on the lines of 250 .

-demetrius

[C-Kwik]

There are way too many factors here that demcj is forgetting when he talks.

2) honda motors have forged internals The b16a block, i dont car what is said, will NOT stand up to 400+ hp without a built bottom end...you are talking about using stock internalson your project...two totally different animals here.3)a bigger turbine will keep things cooler, but most likely be nowhere near a good efficiency range- thats just bad engineering if you use a bigger turbine to compensate for one problem, but sacrifice efficeincy, thus creating another problem.4)ringlands---everyone knows this...i dont need to go into it. If you tune your car with a certain tank of gas, or a good air temp, or a good atmospheric pressure, you will have a good running car. However, when you go out in the streets and are running around in 100 degree heat (im from columbia..i know about sc heat/humidity), you will detonate, and all it takes is once or twice to kiss those lands goodbye. If you get a bad tank of gas....peace out ringlands. Then you got a rebuilt blowed up project car that doesnt run. All for a smidge over 200 hp.5) You cannot compare non-turbo cars built to be turbo cars, with cars that were turbocharged from the factory. Factory turbo cars use a much less aggresive computer program for timing than even JWT. They pull timing for anything...even air intkae temp. JWT doesnt provide for that tha same say mitsu or audi does. Thos cars also come with beefy factory internals. once again- two totally different animals here. 6) 11:1 on 6 lbs is not the same as 9.5:1 on 10 lbs. Boost is not determined simply by lbs. But by heat range, egt, efficeincy, etc...that 11:1 is going to raise egt's a bit and cause tuning to be slightly more difficult than conventional means.If you go this route, you will have to retard timing so much you will lose the low end off boost driveability that you are looking forward to. 9.5 to one is a good ratio for low boost due to the fact it is great for pump gas, and boost timing maps. If you tear open a motor for 11:1 build up...dont be dissapointed when you have to limit yourself to never upping boost. YOu may yeiala round 225 or so. But for the time money aggrevation, and risk...and that low of power...why even try it? I completely agree with wanting to be different. But there are better more logical avenues.

2) So explain why the stock KA can't hold up to 6 psi at 11:1? In most cases, what kills the internals is not the actual downward force, but the heat and shock of detonation. Prevent detonation and the internals should not see any more load than what you would out of a car making similar power.

3) Bigger turbines are more efficient in terms of flow. It has little to nothing to do with compressor efficiency. But it will make more power with less backpressure. It will respond slower, but if response is not a critical goal then reducing backpressure and heat is a good option. From an engineeringstandpoint, cooler temps and less backpressure are a goal, not a poor way to compensate for anything. 4) Detonation are dependent on a lot of conditions. Tuning the system not to detonate under a variety of conditions is key. But you can really only speculate that he might get detonation.

5) Beefy internals do not dictate whether or not detonation happens. And even the strongest forged internals can not last under sustained detonation. While forged parts may give you a slight safety net, you actually don't want to detonate period.

6) Lets look at this from another stand point. If you were to consider the same compressor efficiency, the lower boost motor would produce 3/5ths the amount of overall intake heat as the motor running 10 psi. The 6 psi system would also be able to allow the wastegate to open more and sooner to sustain it's peak boost. This translates into cooler exhaust valves, less backpressure, more flow, etc.

6 psi on a 9.5:1 stock KA should yield about 230. Most dyno's of Ka's at this boost level have results at or around this figure. 225 would be slightly low even for a stock CR KA under 6 psi.

It's not uncommon to see high boost on high CR motors in some of the race motors out there. They run on race fuel, but were talking about 14:1 - 15:1 CR motors running tons of boost. Technology has come along way with detonation control. Turbo technology has as well. Heck 10 years ago, anything over 9:1 compression was considered high. Most performance motors nowadays don't see anything less than 10:1. And keep in mind that high CR motors make power more efficiently and with less heat going to the motor and cooling system.

Certainly, there is a level of risk. But so is turbocharging in general. But in reading many of Demetrius's conversations and posts, I feel he is knowledgable and capable of tackling something like this.

[SSS]

Has anyone mentioned running water injection?

[C-Kwik]

Just so ya know though....I do think that higher than 9:1 with boost is cool as hell. But it has to be done right. Using weak assed factory internals with 11:1 with a plug and play JWT and an afc is outright dumb, even for low boost/power. Forged internals with a standalone is the only way id throw money into a project like that.but hey...its your dough.Just for ****s and giggles...lets go through this.Motor parts:Pistons - about 150 if they are cheapmore so around 250-300 if you want a good set or new.Machine work and rebuild-1000...if its less...watch out unless youll do it yourself.JWT ecu - 550 from stillen--call phil tell him i said wattup.afc 2- 330 afc is just as good for about 260 but doesnt have a much fine-tunability.turbo--do it cheap 1700 with good parts and cutting corners. but more likely about 2500 for a good kit.clutch to take the power - 300better run an external wastegate- you cant afford to have ANY boost creep- low boost on big turbos means creepy boost is out for you!!!!250gauges and a techtom for monitoring a knock- around 300so roughly(very roughly)5600 bucks----for 225+/- ?! Its just not worth it bro.Be different and put a 2jz in it or something like that, but dont just waste money.

I won't go into the internals much as I've explained already, but detonation will killl any part if it receives too much of it. Any fuel management/engine management will work so long as it gives a certain output for a given input and does it reliably.

I think he's planning on doing most of the work himself. Machine work is not all that expensive. Hell, even having a motor with 6 cylinders honed out while the block was still in the car wasn't that bad. And this required a special machine to be brought to the car. I don't think the cost of the turbo system itself is that critical here. Regardless of what PSI, the total cost should not be too far apart that that is a point for argument.

As far as boost creep, it is high boost that requires bigger wastegates. Turbines care very little about how much boost the motor sees. It cares about how much air is flowing from the motor. Particularly in reference to the pressure in the exhaust system after the turbo. In low boost conditions, the turbine needs to spine the compressor to a certain speed to reach a certain boost at a certain engine RPM. To reach a higher boost, at the same RPM, the turbine has to spin faster. Depending on the turbo size, this increase in speed varies. But in any case, to increase turbine speed, you need to route more air through the turbine. But as boost increases, so does the amount of air coming out of the motor. And add in the fact that the gasses coming out of the motor are very hot and has expanded quite a bit, the turbine will have more than enough extra energy to drive the turbine to the desired boost(assuming the turbo is a reasonable match for the boost level intended). This means the wastegate actually has to divert more air. Couple of things that might prove my statement, a least indirectly. If you do some reasearch, you'll find smaller turbos, which require little exhaust energy from the motor to spin to the desired boost are much more susceptible to boost creep. Especially in cases where someone increases boost on a factory turbo. Secondly, if what you were saying were true, factory turbos would come with huge wastegates since they would hit max boost so quickly, and they run relatively low boost. Lastly, just look at how wastegate manufacturer's rate their wastegates. They tend to say what kind of HP their wastegates can handle.

[Chingon]

I love the idea, I asked not long ago what would be needed to build an na monster...and most ppl told me to go turbo...bla bla bla. Well, I like your high comp low boos idea. I mean, if ppl over at club4ag are doing it, why can't we with more displacement?

PS: which oem pistons with the 11:1:1 are you using?

[smug510]

hey demcj im with you, this is a great idea , yes 6 lbs at 11.1 comp will probably make the same hp but what is important here is the power curve, if you are making 250 whp at 5000 rpm you will have a peaky power curve but if you are making 250 whp at 2500 rpm you will have a flat power curve allowing you to have that 250 hp from 2500 to redline not to mention tourqe up the a** , sounds like fun

[C-Kwik]

Doubtful he will make 250 HP at 2500 RPM. He would need to be making 525 lb-ft of torque at 2500 RPM to achieve that. A high CR motor will make more power off boost, and respond quicker.

[SingleCamSam]

hehe, if you made 250hp from 2500 to redline your torque curve would have to sink like a rock!

[smug510]

it was clearly an example to show the difference between a peaky curve and a flat curve i didnt think you would take it that seriously

[APEXi240]

Ummm...for what its worth, SCC turbo'd their Matrix (which has 11.5:1 compression). 7psi on 91 octane, in Cali.

I understand that it is a completely different engine, but its still really high compression, and they did it with no real problems, so why can't a Nissan?

[C-Kwik]

it was clearly an example to show the difference between a peaky curve and a flat curve i didnt think you would take it that seriously

But higher compression isn't going to change the shape of the curve. For the most part, it will only shift everything up.

[smug510]

well imo i have ridin in both a low comp turbo car and a high comp turbo car and the low comp seems to have nothing bottom end and all of a sudden have a boost of power, and the high comp has alot of power down low and instead of flatining out the turbo makes power topend , but perhaps its my experience tuning v-tec hondas talking b/c nissans are a whole lot different

[C-Kwik]

The amount of boost being run can have a huge difference there. If the low CR car is running higher boost and the high CR car is running lower boost so that they make about the same HP, the low CR car will feel like the turbo is kicking in very fast. Off boost, the lower CR motor will make less power, so it will go from low power to high power. The higher CR motor in the same case would go from moderate power to high power. You would not feel it as a big kick in power. It's all relative.

[Projex240]

OOOOOOK

...honda motors boost in bolt on form...not true? Honda owners who turno up the boost on a honda have to re-tune the e-manage for the hgher boost. They will not turn up in BOLT ON FORM...if they do...they may only last 2-3 months...weve got idiots here in columbia that have tried and failed at doing it

The bottome end of a honda:No..i said what i meant. Hondas have a forged bottom end. Even if they do make impressive hp with boost...they are also more inclined to make horsepower at higer rpms..theyre honduhs. My mistake....i though i saw a post were someone made a refernece to a honda with a 400hp stock bottom ended car.

The t04e 60 trim is more effieceint thatn my 50 trim? at 6 lbs of boost?! Please. Look at the maps. And waht does a t04e 60 trim have to do with a turbine anyway? 60trim? 60 trim what???compressor? When you say t04e 60 trim...you should be more specific when talking about efficiency. Is your turbo a t04e 60 trim compressor? what turbine size housing? what stage or trim turbine wheel? Ceramic wheels? Standard wheels? The 50 trim t04e compressor is a much broader efficiancy range than the 60 trim. at 6lb pounds of boost you wont even be close to the efficiency range of a 60trim wheel.

Who cares about the ringlands of the cars you are reffereing to? They are also running 9.5:1..not 11:1 CR. People have a hard enough time getting a car tuned to run with no detonation on 9.5...much less 11. And you are using SOHC pistons. When tearing it down...why not just throw in somme forged 9.5:1 and be done with it? Taking a risk on pistons that, regardless of popular belief, do not stand up well to boost over time. Yes..there are a some that do just fine, but they are not commonplace at 260+ hp, and are not running 11:1 cr. Ringlands on ka pistons suck...and thats the truth.

This was afor the most part a general statement. Seomone made a reference to audi cars...i was simply pointing out that turbo car factory ecu"s are better equipped to handle boost better than even re-pro ecu"s for non turbo cars.

The final static compression with 11:1...

It has been increasingly common on the 240sx.org forums to see peolpe who have never built a turbo motor up to come up with new an inventive ideas. However these ideas are fed by regurgitation of info they have read and/or misinterpreted, and hold as gospel. You cannot just sit and crunch numbers to come up with a final CR and determine a power figure given x amount of boost. Then these ideas are backed by nothing but thoery, and a poor attempt to outwit someone by trying to have a verbal contest on the forums, by just spitting out info here and there. Its gets old, but hey, to each his own. I BUILD 240's. Ive gone through the same thought process as everyone else. And i have tried to do the thing that i see others trying to do....i just try and help em out.by heading them off at the pass before they get into a money pit or a point they cant get past.When it comes to tuning this sucker to run. Even if you are taking a different route as others to try and acheive the same thing, you wont have good tuneability. What you were going to use was a JWT ecu, adn an afc? How would help you tune for timing? Retard it too much with the dist, and you heat everything up...you wouldnt want that with the high 11:1 created heat already. Advance it too much, and theres your detonation problem. This is just not worth the time and effort for anyone. Unlas a standalone is involved and racecar with nothing but race ags to run on...a high cr with a turbo is just not a good idea. Its sees too many unfavorable conditions.And about the ting with the matrix with 11.5 to one. It was really cool, and ran good...until it blew up a month later.And it was tuned by XS engineering.