Originally posted by La fiera: ... they feed the opposite side. I was able to locate them 7 inches higher up for better atomization and to absorb heat from the incoming air.
The Falconer intake does that too, probably for the same reason. The injectors are high up in the manifold.
The Falconer intake does that too, probably for the same reason. The injectors are high up in the manifold.
Yep, Google University graduates know nothing about this, they just follow trends. Most of the time I have to go back in time to leap miles and years fordward!
Yep, Google University graduates know nothing about this, they just follow trends. Most of the time I have to go back in time to leap miles and years fordward!
injector placement is an interesting topic, the further away you are, the more cooling, the closer you are, the higher the accuracy of the supplied fuel. the trick is finding the middle ground that works for each application, and the ever important packaging problem, it has to fit on the engine to work!
------------------ "I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."
injector placement is an interesting topic, the further away you are, the more cooling, the closer you are, the higher the accuracy of the supplied fuel. the trick is finding the middle ground that works for each application, and the ever important packaging problem, it has to fit on the engine to work!
Shower injectors above per-cylinder throttles have long been the way for high RPM engines... but that doesn't work for OEM emissions and drivability needs. Highly optimized racing carbs deliver better mixture *quality*, in terms of mixture homogeneity and dropley size, than port EFI, although port EFI has superior metering and mixture ratio control. Most port injectors shoot one or more streams rather than a shower or spray of droplets. The need for better atomization in direct injection applications drives 4 digit fuel pressures.
So with large upstream injectors, theoretically there's a sweet spot for injection timing that results in all the fuel injected getting trapped in the cylinder on a cycle-by-cycle basis, rather than averaged across multiple cycles. This window is easy to hit with port injection, but increasingly offset from the valve events as the injector goes further upstream.
In addition, even with stoichiometric combustion in the chamber, an engine with a lot of overlap that traps all the fuel in the chamber will show lean on an EGO sensor because it's sending air out the exhaust port.
[This message has been edited by Will (edited 05-23-2021).]
Rei, ever thought about doing ITBs? It'd be a packaging nightmare, but you're already into tall intakes.
That's in the drawing board. Meantime the intake for the "9,000RPM Supernatural" is almost finished. It's the SR1 Supernatural intake which I dubbed as "Meet the fogger", the nickname implies its purpose.
Did a compression test today after some miles on the rings and all cylinders are right at 235psi, the 3.4L was about 218psi. The 3.4L had a 244@.050 duration cam and the 3.7L has a 250@ .050 cam. Even bleeding more compression with a bigger cam the 3.7L is looking to my spectations! Bone cold engine.
[This message has been edited by La fiera (edited 05-28-2021).]
Just out of curiosity, what's the static compression ratio?
According to my calculations taking every detail made to the heads and short block into account it is 11.58:1 exactly. Its a huge difference from the calculated dynamic compression of 15.99:1 which is the product of the compression test results divided by atmospheric pressure. The 3.4L also had the same difference in dynamic compression being much higher than the calculated static compression.
According to my calculations taking every detail made to the heads and short block into account it is 11.58:1 exactly. Its a huge difference from the calculated dynamic compression of 15.99:1 which is the product of the compression test results divided by atmospheric pressure. The 3.4L also had the same difference in dynamic compression being much higher than the calculated static compression.
Would you mind showing your math on this? I don't believe DCR can be higher than SCR, since it's a function of stroke and cam timing. Atmospheric pressure doesn't really come into play since it would be a variable depending on where you are, and DCR doesn't change once calculated.
What did your combustion chambers CC out to once you were done working the heads? Curious as I think you said your pistons are above deck at TDC now. DId you have to cut valve reliefs?
Are you giving up on pump gas and turning this into an E85 only ordeal?
Fishsticks, thanks for posting that. It actually makes a lot of sense. I'd love to see a timeline laid out showing a cylinder's pressure over time, when valves operate, piston position, pulse width of the injected fuel and spark. It would help to see the variables we can play with on that timeline for engines like ours with fixed valve timing. I don't know if I agree that there is No Compression until the intake valve is fully seated but it does highlight that at least Some of the compression stroke is wasted, early in the cycle.
[This message has been edited by Notorio (edited 05-30-2021).]
Fishsticks, thanks for posting that. It actually makes a lot of sense. I'd love to see a timeline laid out showing a cylinder's pressure over time, when valves operate, piston position, pulse width of the injected fuel and spark. It would help to see the variables we can play with on that timeline for engines like ours with fixed valve timing. I don't know if I agree that there is No Compression until the intake valve is fully seated but it does highlight that at least Some of the compression stroke is wasted, early in the cycle.
There are a lot of moving parts in that timeline, especially when you factor in things like cam overlap vs engine RPM. I'm not an ME, just a guy who's built a lot of engines, so the calculus involved in generating that is a bit beyond me.
It's interesting to see the various methods camshaft manufacturers have used to manipulate the intake charge. Example:
Comp XER lobes open relatively gradually, but then slam the valve shut very quickly to try to start building compression ASAP.
Ultradyne/Lunati Voodoo lobes open the valve extremely fast to maximize use of the intake stroke on heads that flow well at high lifts, but close the valve much less abruptly than Comp XER lobes.
[This message has been edited by fishsticks (edited 05-30-2021).]
There are a lot of moving parts in that timeline, especially when you factor in things like cam overlap vs engine RPM. I'm not an ME, just a guy who's built a lot of engines, so the calculus involved in generating that is a bit beyond me.
It's interesting to see the various methods camshaft manufacturers have used to manipulate the intake charge. Example:
Comp XER lobes open relatively gradually, but then slam the valve shut very quickly to try to start building compression ASAP.
Ultradyne/Lunati Voodoo lobes open the valve extremely fast to maximize use of the intake stroke on heads that flow well at high lifts, but close the valve much less abruptly than Comp XER lobes.
Very interesting!
La Fiera, you've mentioned that you get custom grinds for these builds. Can you tell us about these kinds of decisions you are making? Is there software that can simulate the results given a set of variables?
Comp XER lobes open relatively gradually, but then slam the valve shut very quickly to try to start building compression ASAP.
Ultradyne/Lunati Voodoo lobes open the valve extremely fast to maximize use of the intake stroke on heads that flow well at high lifts, but close the valve much less abruptly than Comp XER lobes.
The Comp lobe might work better with a long rod (or small port) flat tappet engine at high RPM while the Lunati lobe might work better with a short rod roller cam big port engine with a carb.
The Comp lobe might work better with a long rod (or small port) flat tappet engine at high RPM while the Lunati lobe might work better with a short rod roller cam big port engine with a carb.
Yep. Lunati cams seem to have a stronger vacuum signal at similar durations and (usually) make a touch more torque. They're a bit rougher on valve springs though.
I've heard of people seeing accelerated valve seat wear from some of the more aggressive Comp lobes, which makes sense.
La Fiera, you've mentioned that you get custom grinds for these builds. Can you tell us about these kinds of decisions you are making? Is there software that can simulate the results given a set of variables?
Engine Analyzer Pro is a pretty good sim software. I use it to make cam choices for engines. It takes a lot of input variables, and the more info you have to plug into it, the more accurate the results that comes out of it.
La Fiera, you've mentioned that you get custom grinds for these builds. Can you tell us about these kinds of decisions you are making? Is there software that can simulate the results given a set of variables?
I personally don't use any analizer software. I use simple math with the128 rule and modify it depending the application and expectations.
Changing the subject, I did some front facia removing to make room for the new aero package. The original hood was about 54lbs and this one is 21lbs. I was able to take off 40lbs off the front nose. I want to add 3 times that on down force with the least possible weight to make the downforce gain dynamic. so lets begin!
Idle tuning is done! Only took me one hour or so to get it where I wanted it. My neighbor from around the corner came to my driveway with his grandson clear an argument they had about what was making that sound. The grandpa said "it sounds like a chain saw" and the granson said, "No grandpa, it's a muscle car". So, they had to come to my house to find out. Grandpa was very impressed, "that little thing is making all that sound?" Were his first words when he saw the engine compartment. We chat for a while, they took pictures and I found myself another Fiero fan, the grandson! He wants a Fiero for his first car!
My neighbor from around the corner came to my driveway with his grandson clear an argument they had about what was making that sound. The grandpa said "it sounds like a chain saw" and the granson said, "No grandpa, it's a muscle car". So, they had to come to my house to find out.
Originally posted by Lambo nut: So they were both disappointed?
No, turns out grandpa was a racer back in the 60's and he loves tunnel ram intakes. He was really impressed with my intake. The other thing that he was amazed by was the change in engine sound from idle to hi RPMs. I don't know if you've seen the video where I take the car out for the first time. The people I sent that video to had different oppinions about the sound. Some said it sounds like a rotary, others said it sounds like a two stroke, others said it sounds like an F1 car from the 70's and my brother said it sounds like a Group B Rally car from the 80's. The one thing I get from those feedback is what I'm after, one unique engine with one unique sound that no one has.
Glad to see that you are OK. Bravo on the quick action to save your car and garage. It's a bit sad to see another 'Fiero on fire!' incident but it's a good reminder for us all to have an extinguisher handy at all times.
Glad to see that you are OK. Bravo on the quick action to save!\ your car and garage. It's a bit sad to see another 'Fiero on fire!' incident but it's a good reminder for us all to have an extinguisher handy at all times.
I have two now. One pointing to the gas tank and another one pointing toward the firewall header. And another one handy to use it whereve I need to. Not just with a Fiero, but you neve know
I couldn't tell from the video... it was an oil leak around the filter?
What happened was that I modified the adapter that mounts on the block because it has a restriction. By doing that I took out half of the threads on one side. I must have damaged the threads when doing that because when I was installing it it was hard to turn. I meant to replace it but I sincerely forgot about it.
What happened was that I modified the adapter that mounts on the block because it has a restriction. By doing that I took out half of the threads on one side. I must have damaged the threads when doing that because when I was installing it it was hard to turn. I meant to replace it but I sincerely forgot about it.
D-oh! Filter adapters are apparently finnicky... mine is taking up a lot of time as well.
Do you need to replace your adapter or is it ok as is? You could screw their filter onto your current adapter, right?
My kit consists of 4 parts:
1- Oil bypass adapter
2- Lines
3- Remote oil filter location and a good oil cooler. z/ But I decided to go back and investigate what caused the Oil bypass adapter to come off the block and cause that fire!! Look at this! That part cocked to the side attaches to the block and then bypass adapter screws to it securely right, wrong!!!! Look at the angle. that's how much wobble there's in the threads. Obvioulsy this oil bypass adapter has the wrong threads, it's standard not metric.
So, the question is; How did it held up all these years and now decided to give up?
I spend a lot of time blueprinting the oil pump and the bypass itself, I must have increase its volume and pressure by 20%at least just my by massaging the oil pump and the adapter.
Look at this for example: This is how the adapter is when you get one. Do you see that wall there? That creates cavitation and creates bubbles in the oil.
Now, this is how I fixed that! I smoothed out the oil flow by blending those walls in. Now the pump works more efficient, not dealing with restriction and now it can put out all that flow and pressure without costing energy.
Since the oil pump is working more efficient in tandem with the oil bypass adapter, now I can understand why the fire took place! I had the wrong threads all along!!! The nipple being cocked gives you an idea of how much play there is between the nipple and the bypass adapter!
[This message has been edited by La fiera (edited 07-07-2021).]
