Devan Plantamura

Hey guys, pretty new here. Trying to figure out some stuff with possible power output. I have a 1990 1.6 with a built bottom end. on e85 with 750cc injectors, garret 2560r and some other motor goodies like the ati super damper. I do have the flyin Miata manifold and full exhaust minus the racing beat cat delete. Anyways I was at a beautiful 16lbs of boost with the car and driving what felt like an ethanol drunken 300hp. Unfortunately, didn't make it to the dyno this week as i should have as a buddy of mine and a very amateur tuner wanted to save my map on his computer and my computer so we had a copy of the tune safe in case anything happened. Well that anything happened. He deleted my complete map when updating the firmware and I'm back to zero. But Brett from Dallas Performance is tuning it. We have a very basic street tune at 5psi until a part he wants on the car comes in.


So what kind of power can i make on e85, 16-18lbs of boost, and forged internals. I know with a bigger turbo matt out of florida is making 600hp with a stock top end. I also think most of the people turboing 1.6s arent running e85. All the e85 builds ive seen are coming from 1.8 builds. So until i get the parts in im going to be waiting to bring it back above 5psi. I know the turbo maxes at 330hp and I believe 20psi. Let me know what you think.

Full_Tilt_Boogie

iTrader: (1)

Edit:
I failed at reading comprehension.

shuiend

iTrader: (24)

Between 260-280whp will be where you most likely top out at depending on how the dyno reads.

Devan Plantamura

You think ill be okay at 18lbs of boost? should i just chill at 16, maybe go max the turbo out at 20lbs or does that end up causing unwanted and premature wear by pushing a turbo to its max psi?

sixshooter

iTrader: (12)

I'm curious how you are reading max PSI for the turbo. Are you just looking at the top numbers on the chart for the compressor map? Or are you choosing a particular efficiency percentage you are not willing to exceed?

It would probably be beneficial to note for anyone who might be reading that is not aware that boost pressure is not a measure of how much power an engine will make. Boost pressure is a measure of back pressure against the turbo attempt to force air into the engine. The higher the Boost, the more the engine is restricting and killing the airflow. The number you wants to pay attention to is the number of pounds of air on the horizontal axis of the compressor map. For every measured pound of air a given amount of fuel can be burned and therefore a given amount of power can be generated. More pounds of air flow equals more horsepower. Boost is the engine fighting against those pounds of air.

A small turbo like yours might make 220 horsepower at 15 psi of back pressure whereas a larger, free-flowing turbo might make 220 horsepower at 8 pounds of back pressure. Making the engine or exhaust breathe better might cause the engine to make 220 horsepower at 14 PSI with your turbo.

Please post up a copy of the compressor map of the turbo you are using and let's see where it starts losing efficiency theoretically.

ryansmoneypit

iTrader: (6)

That is a really good post right there ^^^^ and will be great for anyone who has not learned this yet.

shuiend

iTrader: (24)

I would make sure you get to MBT in your spark table on a dyno, then watch and see how IAT's do when you do several runs in a row. Then base boost and power off what seems safe.

themonkeyman

Surprised to see you running stock ignition still, I would think LS coils or the like would give you a bigger margin

Devan Plantamura

So Im a beginner at reading maps on the ecu and tuner studio, im leaving it to a proffessional whos well versed in tuning to handle that. Id have to disagree that my car was only making 220 horsepower at 16psi of "backpressure" on e85. I have a buddy whos dynotuned pump fuel car was allegedly making 220hp at 8lbs and i left him in the dust when he was up to 14lbs. So i think your underestimating my cars potential on the amount of power it can make with the 2560r 60trim turbo. its rated for 330hp at 20lbs and many people make 220 on pump gas at 8-10psi on the same turbo. As to your way of explaining how the turbo works I apreciate it, maybe you can direct me to a video to explain it to me with some diagrams or pictures as im definitely a tactile and visual learner, I can definitely comprehend a lot from reading the internet but you lost me there. But everytime I ask for opinions from the internet about numbers im making you guys throw out some **** and tell me i cant possibly make what I am/was making so ill leave it to a dyno to tell me.

Devan Plantamura

[QUOTE=themonkeyman;1551208]Surprised to see you running stock ignition still, I would think LS coils or the like would give you a bigger margin[/QUOTEiM
Im getting there. its been an upgrade Ive been getting around to. I was going to do it but now I have to make sure I can cover the tuners fees.

SpartanSV

The turbo is rated at 330hp but you won't be making that much at the wheels. I have the same turbo and would be very happy if I was making 280 at the wheels at 230kpa.

Your buddy didn't make 220 at 8psi.

Arrogance won't get you very far here

irollgen4s

My 1.8 made 215whp with a 2560 t28 at 10psi on 93 pump gas. my 1.6 on the exact same turbo at 15psi felt pretty good but it obviously lacked the low end and spool of the 1.8, id still say around 215wheel or so.

I figure the 2560 would tap out around 18-20psi around 240-250 wheel. Maybe ~20 wheel more with e85 and some timing.

It makes 195whp/175wtq repeatably at 7psi on my stock 96 1.8.

This is all on a dynojet at sea level on a ~78 degree 82% humidity day.

ryansmoneypit

iTrader: (6)

I ran that turbo to its maximum on a full built, vvt, big valve head, 1.8, 84mm pistons, aggressive timing, pump 93,.I doubt I was at 300. An engine with 20% smaller displacement isn't making more than what mine did.

Turbo values are theoretical

sixshooter

iTrader: (12)

My numbers were to illustrate an idea of how things work and were not chosen to reflect your specific output. I hope you didn't stumble over the numbers I made up and miss out on my purpose regarding explaining some turbo theory.

If a manufacturer lists a maximum horsepower for a given turbo it will be a theoretical value based on best possible flow through a theoretical engine (excellent heads, race cams, unlimited ignition timing) and not one of our trash tractor engines with tiny ports, bad port/valve angles, and very small cams. And that value will be for that imaginary engine on a test stand dyno with no accessories or drivetrain attached. So, expect a fair amount less if measuring output at the wheels as we do.

Compressor maps tell us the expected peak efficiency range of a turbo. They give us pressure on the vertical axis and pounds of air on the horizontal axis. As mentioned previously, the pounds of air gives you a reasonably good idea of the capacity of the turbo to make power. Pressure ratio on the vertical axis tells us the tolerance of the turbo for back pressure and what level of efficiency we can expect at what amount of back pressure. Low efficiency means poor flow and much higher level of heat generation instead of actual power being produced. Energy from the exhaust is not all turned into pressurizing and moving the air on the compressor side. Much of it is converted to heat instead of doing efficient work moving air. That lack of efficiency means wasted power and poor performance.

If you look at a compressor map you will also see rings with numbers and percentages. Those numbers and percentages are the efficiency of that turbo in that range. The higher the number the less energy is wasted to heat and the better the turbo makes power for the engine. Running a turbo outside of its efficiency range will yield more losses than gains. For example, (this is an example and not specifically about your car in case you are trying to do that again) a particular turbo might make maximum efficiency at 12 to 15 psi and might taper off significantly moving up towards 20 psi. Running that particular turbo at 20 psi may possibly generate a little more power than at 15 psi but it might make 50% more heat which causes the air going into the engine to be much hotter, giving the engine less of an increase in power and cause the timing to need to be retarded to prevent detonation. In other words there might be significantly more percentage increase in gain between 12 and 15 psi than between 15 to 20 psi because of the loss of efficiency. A different turbo might not make peak efficiency until 20 psi because of wheel shape and size. This is why understanding a little about compressor maps can be useful in selecting the right turbo, deciding how to proceed with your upgrades, or or even when adding more boost is a bad idea for a particular turbo.



Looking at your compressor map I see that they are being very generous in calling it a 330 horsepower turbo. It is only a 330 horsepower turbo in a very, very narrow corner of its operating range and only at a very specific pressure ratio. I would expect if you hit THE sweet spot with it on a stock 1.6 you might achieve 270whp after all of the drivetrain and heat losses depending upon how generously the dyno operator "smooths and corrects" the results. They can give you 40whp just by manipulating the settings if they think you want Disney numbers.

I wouldn't exceed 18psi, looking at the compressor map.

Stock 5 speeds usually don't survive past 250whp.

curly

iTrader: (25)

Just dyno'd a full FM setup '94, stock engine with an S2 intake manifold. Made 10-20hp more than your figures. 250 took 13psi, and there was plenty more to give. With the right mods, I'm confident it'll make 300hp. Same Dynojet and conditions you mentioned.

irollgen4s

That makes sense. I failed to admit that I was indeed having some weird quirks with my wideband which was causing the tuner to keep it pig rich the entire time.(My cars wideband reading 10.8, dyno wideband was reading 12.2); That and the intake manifold easily explain 10-20 wheel everywhere over my setup. And how much timing if i may ask? I topped out around 17/18 degrees, anymore had minimal(5hp) gains so we took the timing back out.

for another idea of perspective on the dyno, my buddies 94 manly rods 9.0 cp pistons 99 head trackspeed 6258 setup on the same dyno on a very similar day made just over 200wheel on 6psi. boost solenoid was screwed up so didn't get to raise it up at all but helps give you an idea of the dyno calibration.

To keep it back on topic, the 1.6 should make similar(within 10% or so) peak numbers up top, it's just going to take more boost and have more lag and less torque ultimately. When i had my 1.6 i dug around for 2560 dyno's like crazy as i wanted to see what the spool would be like.

shuiend

iTrader: (24)

Just so you know I have never seen a 2560 break 300whp on a dyno in a miata. I have seen between 290-300whp several times, but nothing breaking over. With a perfect manifold, good exhaust, and optimized tune I think a 2560 on a 1.8 with E85 could hit between 310-320whp. With a 1.6 I don't think you will get there unfortunately. I have seen a friends built 1.6 with a 2787x or something have trouble breaking 300whp with 93.

curly

iTrader: (25)

Don't have my tuning laptop in front of me, but off the top of my head on the 250hp/14psi pull it was around 10 degrees, and the 210hp/8psi pull was around 16.

sixshooter

iTrader: (12)

Ground for o2 should be common to MS ground to reduce voltage offset that effects reading. Recalibrate sensor occasionally also for maximum accuracy.