Cylinder head flow data Options

[Jeff Bonanno]

(IMG:style_emoticons/default/pray.gif)

Jake, i was checking out the stf posts and in one you said that there were things you could get in trouble for saying - were you referring to proprietary engine configurations? do you have patents or are they trade secrets? just curious! (IMG:style_emoticons/default/smile.gif)

[Jake Raby]

Can't really patent an engine combo...

I can get "In trouble" by telling the truth about how some things suck, or how junky they really are...

Most crap you buy is not tested at all-

[Bleyseng]

You can't get in trouble here Jake expressing your opinion! You can get in trouble if you say "Crapworks Motorsports parts are a effin joke"
Most of us know you have built tons of engine combo's so you know what works in real life by trial and error. (finally someone who posts with real data instead of the shit from a computer program)

I still wish you would sell parts like cams combo's, etc that you have made to your specs. (IMG:style_emoticons/default/wub.gif)

Geoff

[Brett W]

Dammit Jake, If you would have read the post you would have seen that I referred to an "article" about the flowbench using multiple vaccum cleaner motors. I can assure a flow bench is not a big waste of time.

Whether you see the worth in the reasearch gained from it really doesn't matter one bit to me. You have your clientel and I will have mine. They will be two different groups of people with two different sized budgets and requirements. I have no reason to doubt your work and never said I did, so back up.

[lmcchesney]

Thanks Guys,
Sorry Bret, I did not know you enough to realize the sophistication level you already have obtained.
Charles, that is very similar to the flows previously posted. Your intake flows continue to .700 lift reaching the 200's. I thought in most heads, flows tend to plateau at ..35-.400 lift. Are you using .700 lift? the exhaust flows are not as good with about a 6% over stock flow. Did you remove the guide boss?
Jake, I always appreciate your input. Your work DOES speak for itself. I certainly have not spent years designing and building engines. In fact, I am the amateur that has some jealousy of the opportunity you have of designing and testing by its creation. I have and will always have tremendous respect for you and your teams efforts.
However, somewhere the data must be off. The flow data is from Tim Studdard's Grassroots Motorsports 914 project (GRM 18(6):114-120;12/01) and Dyno is from (GRM 19(1):87-92; 2/02) which is a near stock 2.0L with Web Cam 73 grind. His post yesterday http://forums.pelicanparts.com/showthread....threadid=146327, seems to show the combination works. Where do you think the difference is?
Geoff, you continue to be a mentor for our project and steadfast source of realistic information. I agree, computer programs do not produce engine results, as I have discussed with DD. I believe I use the program to help me think how the components interact.
RobotVac, First Amendment rights were created by those with the strength to use them for the benefit of all and defend them. However, its use requires responsibility for their use and results. Are you being responsible?

God's Blessings,
L. McChesney(Andrew, Eric and David)
lamcchesney@netzero.net

[Bleyseng]

Hi Andrew, Eric and Dave,
The problem I see with your project is that you want to build a higher hp motor for racing but still keep it streetable and use Djet FI. Lots of people have tried this to some degree in the past.
Street driving likes motors that are torquey and can pull the car away from stop sign, stop lights etc. and stay cool for hours of driving.
AX driving likes a motor that is torquey and can pull a car out of slowing down but still rev quickly. Cooling is not that big and issue as the runs are only for 60 secs.
Tracking likes a motor that revs higher and produces is hp up high for high speed blasts like down a straight away but still needs to cool as laps can last 30 minutes.

Its an interesting problem that most before have just gone to carbs or a different FI.
Geoff

[DNHunt]

Geoff

Can you tweak the D-jet to give enough fuel at WOT. I know the stock cam falls off about 5k and the exhaust is a bottleneck so it's not a problem on the street. But on the track with more displacement, better flow, more cam and a freer flowing exhaust, they'll be pumping a lot more air. Can they provide enough fuel?

I hope I'm wrong but, it's sure getting hot in here.

Dave

[lmcchesney]

Dave,
D-jet article says that the 2.0L injector can flow 380cc/min.
I believe the 2.0L engine uses 312cc/min at WOT.
L. McChesney

[Bleyseng]

Depends on the MPS, but I easily had a A/F mix in the 12 to 1 range at WOT from 2000 to 5000 rpms. I had to adjust it to 12.5 to 1 for about the right mix.

There are other problems that can play into a lean A/F mix on these cars. Old fuel pumps, clogged fuel filters, clogged tank inlet screen, and wrong MPS or mis-matched Djet parts.
Just as you Dave had to to assemble everything to get it running with the Megasquirt, you had to go to get it dyno'd to set the fuel MAPS. Everybody should have their cars tuned/checked for the right A/F mix. ( this includes the carb guys)

95% of the Djet cars that get brought to me to check out are running lean, way too lean. The other 5% have a problem like a injector is unplugged(ChrisReale)

Not only does the stock cam fall off but so do the valve springs! The heavy stock valve train can keep up with the revs. Damn I wish I could afford those ceramic lifters!



Geoff

[Brett W]

If the stock injectors are already at 85% in a stock application why in the world would you try and give the engine more airflow. Anyone know what the duty cycle is for the stock injectors? Why bother with the stock djet? It is not worth it. Go with carbs for the cheap route or run a standalone FI. It is getting cheap enough that you can buy it for about the price of a new set of carbs. The stock cam was meant to give you good torque around town but not meant to have much top end. Porsche would have hated to have a car that was half the price of a 911 outperform it.

[seanery]

If you weren't such a fucking moron we would have let you come back in peace. But no, you're a racist dumbfuck who can't keep his closed-minded mouth shut.

Go play with the nazis and the kkk somewhere else and leave us the fuck alone. We really don't like you here. AT ALL.
You have absolutely nothing positive to contribute. You've been a major pain in the ass since day one.

So, do yourself a favor and LEAVE!

[lmcchesney]

Thanks again Geoff.
I think the main thing is my sons and I can apply the theories we learn.
We reviewed the ruel books again. SCCA seems open for D-jet or other FI. PCA still requires D-jet to stay in the street prepared class. I was hoping to find a tech inspector for both to review and confirm our inturpertion.
When we use a modified cam on the simulator, I can generate a good low end torque by advancement of the cam and also still have good top end (176HP at 5500 - 6000 RPM) with retardation of the cam timing.
I want to get some further advise on split duration cams. Since our discussion on the limitations of D-jet focuses on the overlap, trying to design a cam with near stock overlap, longer intake duration, say 262° and increased exhaust duration for imporved temp control. However, with the increased valve size and porting of the exhaust side, I don't think I need to lengthen the over lap or take away from the power stroke. Besides, all my mixes are with a CR of 8.5-9.0:1.

Brett, having cabs is wonderful if that works for you. My parts do not include carbs. Also, it seems most of the advancements have already been done in carbs. If you look at the responses to our discussions, they seem to be enjoyed. Try one yourself.
Post " Putting Carbs on a 2.2L Type IV. Any suggestions?" See what happens.

L. McChesney and The Guys

[DNHunt]

L

You sure about that flow rate on the 2.0l injectors at WOT. I've never seen anything approaching 50% duty cycle. MS has a display that shows duty cycle as a bar graph and a percentage. Rough calculations show these injectors should be good to about 250 hp (probably a little less since our engines need to run rich for cooling). I feel confident the injectors can handle the job. If Geoff says he can tune the MPS to meter the right amount of fuel I'd bank that.

I would worry about vacuum signature and I'd be concerned about the intake runners and plenum. Someone with more knowledge of intake design may be able to jump in. I know there is some ram effect and that the runner length and diameter, and plenum size affect the rpm band where this aids performance. There are formulas to calculate this (way beyond my knowledge and skill). From what I've read, these can give you a starting place but testing is needed to get something that really works and physical constraints such as engine bay layout tend to compromise the results. The key is you want that effect to fall within the torque band. Significant changes to the internals are going to change this band and whether the stock intake system aids or inhibits the engine's performance then becomes a crap shoot. Obviously, the smaller the change the better chance that you'll benefit from intake tuning inherant in the stock plenum and runners such as it is.

I'm sure there are performance gains from engine design available with FI (stock and aftermarket) but I think it's going to be tough to go much beyond mild cam change, slightly ported heads, better exhaust and recalibrated MPS with D-jet. More is certainly available with aftermarket FI but it looks like a frightening place to me. Looks like a lot of money and lots of risk.

Dave

[Brett W]

Do not rely on Desktop dyno to give you accurate numbers. Unless you are using something like Ricardo Wave 5.0 or Engine Analyzer Pro the numbers you get won't even be meaningful. You can not get 176 HP out of a stock injection based NA combination. The stock plenum cannot flow enough air to support that. If you are running an aftermarket injection using the stock plenum and runners as a you still won't make it. You need to completely redesign the system. With a 2.0-2.2 you will make at most 120 on motor with Djet. I don't care to take the risk of complete motor melt down due to some POS 30+ year old FI failed and melted all the pistons because it went lean at WOT during a track session.

The amount of money that you will put in this engine will be large, why wate the full potential of this motor by trying to run it through a huge restriction. Carbs are the cheapest way to maximise engine potential. The right way to do it is buck up and by the standalone fuel injection and make some real power. Or just be satified with 110hp.

[Bleyseng]

The proven combo with Djet is a 2056cc motor which makes about 115hp or 120 with the Tangerine Header, Webcam 73, portedheads, lots of carefully engine assembly.
I have heard of engines running 100mm p&c's successfully too but those are long gone.

Brad Roberts has built alot of these motors which last on the track or AX course.

The problem is jumping up to a 2270cc motor with Djet, no one that I have heard of (in 10 years) has done it including Jake. I think this is what Brett W is talking about, why beat your head against the wall unless you have lots of money to burn in this experiment. I know lots of people have tried to do this in the past using 103mm pistons and failed.
Hey, if you are gonna try great, I think we will all lend what knowledge and support to try to make this work.


Geoff (IMG:style_emoticons/default/beerchug.gif)

[Mark Henry]

You sure about that flow rate on the 2.0l injectors at WOT. I've never seen anything approaching 50% duty cycle. MS has a display that shows duty cycle as a bar graph and a percentage. Rough calculations show these injectors should be good to about 250 hp (probably a little less since our engines need to run rich for cooling). I feel confident the injectors can handle the job.

(IMG:style_emoticons/default/agree.gif)
I don't think I've ever seen over 40% duty even at WOT

As far as flow goes I agree with Jake when you hog out the exhaust port you lose HP. This is true on both the Type 1 and 4. I also have a flow bench and rarely use it. What I do use it for is making sure all my ports flow the same once I've ported a set of heads. I never bother to chart the flows, been there done that in the early 90's.

Guys always get stuck on the numbers...the most HP the biggest flow, it don't mean crap if the engine runs like shit.

[Mark Henry]

I know lots of people have tried to do this in the past using 103mm pistons and failed.

They didn't use Nickies!

[Brett W]

I am not saying don't try it but I can't understand risking a motor due to archaic fuel control just as a home project. For racing that may be different if there was some money involved. I personally would take the computer and chuck the guts and put a more modern system inside the factory box so that the casual observer would not be the wiser and really make some major horsepower. You are free to do as you choose but I would reccommend against it.

Geoff is right there are a bunch out there that do it with mild 2056s but why bother. Crank it to 2.2 inject it and build a 200hp motor, that will walk all over a 1971-2056. Granted my 2056 did make 140 through stock heat exchangers I really think there can be more. So up to a 2.2 stoker motor with a turbo ought to make things more interesting.

[Bleyseng]

No Mark, it was the fact that they changed the VE curve so much and weren't also able to cool the motor. Maybe with nickies atleast you could keep the motor cool enough to survive long enough you could tune it.

I think Bretts idea is the best, just rip out the ECU internals and hide a MS brain in there!


Geoff

[Jake Raby]

When you use "Cast iron clunkers" (103s that ARE NOT Nickies) you are asking for a failure...

In mY opinion when you ask the stock FI to do anything but a 2056 with a 73 grind, you are asking for it as well.... Thats just me, not being a fan of stock FI at all, in ANY application.