ok so ill take that as a no

 

Very interesting, keeping an eye on this one.

 

so this is what i think. if the fuel rail is too small and the injectors too big. then the injectors are dumping the fuel faster than the rail can fill up then you would have lean problems so just making a bigger rail or buying one would help i think. and you would still have the same preshers and a returnless fuel system but with a larger amount of fuel in the rail. ive seen this before on 5.0 mustangs where the bigger injectors drain the rail faster then its filled. what do yall think about this ??

 

So I have a question about blown motors that I have noticed.

Isnt it true that most of the motors destroyed have been running in the 20+ psi range in terms of pressure??

In theory, with a good tune, maybe bleeding off the extra pressure created by a 2.6 or less, to lets say 19 or 18psi, would this help prevent blown motors? You would still get a fast spool, but not as much top end pressure. If you had a good enough tune, would this be enough to help out the issue of blown cylinders?

Im not very engine suavy, so bear with me. I did notice VERY high pressure running with the blown engines though.

ALSO. Ive noticed that the new sky R/L and pontiac solstice GXP is running the "first ever" direct injection ecotec. They are using the same 2.0L engine as ours, but is a turbo setup instead.

Does anyone think that converting our fuel system to the R/L or GXP system would help and be feasible??

 

Subscribing, ened to learn this stuff before I start modding.

 

heres a link to sky R/L:

http://www.saturn.com/saturn/vehicles/sky/pricing.jsp

 

The amount of air pressure isn't really what is causing it.

The problem is many things:

1. How much heat is being created when running way pass an efficiency point
2. Using fuel as a coolant rather than a way to keep a balanced air to fuel ratio for power
3. Oversizing injectors to keep a good injector duty cycle but keeping up with the EXTREME fuel enrichments that is needed (or wanted).

The Sky Redline/GXP does NOT use the same engine. The SS/SC has a 2.0 LSJ motor 9.5:1 compression ratio and other differences (non direct injection). The Sky Redline/GXP uses an 2.0 LNF motor which has direct injection, lower compression (I believe 8.x:1..can't remember what it is 100% right now), Variable Valve Timing, More engineering involved etc.

To convert to direct injection, you would basically have to physically re-engineer the engine to where the fuel injectors are placed in the combustion chamber basically (on top of other things as well) It's not the worry of fuel distribution from the fuel injectors into the combustion chamber but the distribution of fuel to all the injectors being equal.

 

well, I was thinking of putting a 2.6" pulley on the car with 60lbers, but now Im thinking a blown engine wont be worth the trouble....

F%cking GM. I think Im going to buy a Cobra soon...

 

This isn't a GM issue

Most automakers are doing return-less fuel systems on new cars.

 

So in theory what would be involved in a return feed fuel system, and would it solve the problem? or are we not that far yet?

 

We are still trying to figure out what would be the best route.

 

The fuel rail is most likely not the only problem. A larger fuel pump and larger fuel lines. There is a Corvette locally that is running 700+ rwhp and they have the following fuel system.

Custom Fuel system - Dual 255lph pumps
60# injectors
Aeromotive Fuel Rails with -8 lines
http://ls1tech.com/forums/showthread.php?t=703116

 

so, short of direct injection, which as stated above would be basically a whole new engine, we as a community, based on what I have read here (correct me if I am wrong) are looking at a fuel system make over in order to safely make the high horsepower numbers some of us thirst for.

Now, theoretically speaking of course, how difficult is changing the fueling system on a vehicle, also, what parts of our ECU if any would need to be reprogrammed to allow for a new fueling system.

Again, I know little to nothing about it, so I am throwing questions out there that someone with similar experience to myself would ask.

 

Direct injention requires a significantly more advanced computer because of the exactness of the fuel flow. It also requires fuel rail pressures significantly higher. Our fuel rail pressure is around 58psi IIRC. The Audi FSI (Fuel Straight Injection) runs between 434psi-16,000psi!!!
http://www.canadiandriver.com/articles/jk/051116.htm

 

Just as some added information; on a returnless system since there is no flow back to the tank from the end of the rail a problem can arise in which the last injector on the rail becomes clogged due to crap gathering there. I know this is a problem on other cars running a similar system as we have.

 

I wonder if you had a 2.6", dual pass, and a tune that limits psi to 18 max, and a 6.5k redline, would help...

 

I think you're kind of missing the point...

It's not about how much boost you're necessarily running or the RPM you're revving to

It's about the amount of fuel you are demanding and the neglect of fuel when reaching cylinder #4 when you start to oversize injectors.

The biggest issue is that most of the people are messing with the efficiency of the air being created (stacked) and they are greating so much heat (even with cooling modifications) that they need to run to an incredibly rich air/fuel mixture to counter-act detonation. It's gotten so bad that they REALLY need large injectors to keep a good IDC (Injector Duty Cycle) while maintaining a very rich air/fuel mixture. Some people are maintaining a (overall) 11 to 10 a/f ratio which is incredibley rich.

You are ultimately doing this just so you can keep your basically inefficient supercharger and you're doing everything to revolve around it when it will ultimately hurt you in the long run. There is no way you should be running 60 # injectors and you're not even close to breaking 300 WHP. There are many high performance 4 cylinder engines (turbocharged for example) that utilize 42 # injectors and making more power than the people with 2.5" pullies and running leaner a/f mixtures of mid to low 12s.

It's basically about keeping good setup all around, not just fuel tuning and air cooling. Neglecting the compressors efficiency will ultimately bite you in the ass...which is what is happening to the people blowing their ringlands or other engine damage occurances due to detonation (excess heat).

 

so is there anyone on this board that fried there aftermarket pistons due to this issue? Bc even though I have replaced mine I still am extremely concerned

 

so wouldnt the simple solution be to "Y" off the fuel line that is going to the rail and connect each end of the "Y" to each end of the fuel rail?? it would still be a returnless system but should get rid of the pressure drop in the rail because you are now also feeding the rail from both ends.

 

Someone needs to drill their block for 4 thermocouples. Stick on so you can measure the temperature of each cylinder liner.

Im still willing to bet there is an internal heat variance amoung cylinders causing number 4 cylinder to run hotter.

 

The problems remains that there isn't enough fuel to support the large injectors required to deliver the fuel needed. We need a way of supplying more fuel pressure and flow to the rail in general.

I agree with what NJHK said above. The engine is not failing due to the design of the engine on GMs part; the engine is failing because people are attempting to create horsepower in a way that makes the environment in the engine unstable. Modification first and foremost need to be done to the engine in order to accept higher levels of airflow, and then a compressor needs to be provided to supply this airflow.

From what I've seen you could take this engine in the realm of around 300WHP safely if you do it right. Past that point it looks like you'll need to use a more efficient compressor which will not create so much heat that it is all the engine revolves around.

 

Bingo, thats the main point here. The M62 is fighting a losing battle to break 300whp on this engine.

 

^ ^ right. I've said it numberous times. If we had 20 psi with an efficient blower we would easily gain 60-70 whp and that's not even accouning for the thermal inefficiency.

 

so figure if we change the compressor, to what? twin screw? or are we forced to become turbocharged?

 

I Have An Idea!

Lets Drive Our Cars Off A Cliff And See How Much Cooler We Can Make The Engine Temps Through A Straight Nose Dive Into The Ground!

F%ckin M62.....