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pretty sure I had no problem getting to 200 kph (~125 mph) with 4.444 rear and under 8k with short diameter 15” tire (forgot to mention this point in the previous post, though it qualifies as “low gearing”), lost all my logs in a recent computer swap though
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Sounds about right, I'm on a 4.44 rx8 final drive and can hit 130mph in 4th still with 18s.
Also you'll be one of the few delighted to know, I've finally got a Dyno booked for next Thursday. Goal is to figure out if it makes any more juice on 22psi and beyond on pump fuel and 50/50 wmi than validate on dragy.
Gentlemen, what is a safe ish boost level to run on pump fuel and 50/50 water meth?
define safe? a police officer here would say zero, anything else is excessive
Renaults water injection system used on the F1 car from 1982-1986, didn't even turn on until boost hit 2.5bar...without it they were putting holes in the pistons.
its pre-turbo, water only. there is a tank, pump and pressure regulator. i haven't been able to find how much pressure, although it must be over 2.5 bar, or they could have just used boost pressure from the engine
yup thats fair both, think i may have answered my own question here.
I have a SPA trackday on 19th October and dyno on 12th October, so the dyno time will be very conservative to say the least. I'm at 22 psi currently and will see if going up to 23-26psi makes any gains on my setup. Will report back in this friday with actual dyno number.
The Track itself is very taxing on the motor lots of high speed and high g corners. post some updates on this next week!
Turns out I'm running out of my 50/50 water meth mix. Below is the brand I've been using.
As many of you are aware, Mazda recently raised the prices of their brand new 13B engines. I reached out to Mazda to verify, and they provided a quote of £7,250 plus VAT, amounting to a staggering £8,700, delivered within two weeks. At this rate, I imagine more owners will consider engine swaps. It wouldn't surprise me if a new 13b is 10k by the same time next year.
Taking the above into consideration, I decided to invest an additional £20.00 and went ahead with purchasing top-tier racing-grade pro methanol. This choice allows me to maintain precise control over the mix.
I wont be running 100% meth injection. For now, I'm going to stick with a 50/50 water-methanol mixture. This ratio serves as a great compromise for me, providing effective cooling, while also boosting the octane rating of regular pump fuel to prevent knock, detonation, and pre-ignition.
There's a lot of issue's running 100% meth injection on rotaries with pump fuel especially with pre-ignition so I'm not gonna risk that. I may consider running a spicier mix, when I have more data on how the new 50/50 mix performs compared to the previous mix.
I hit the dyno at Garage Whifbitz to test the current setups efficiency and specially how the new G35 1050 performed.
Next Thursday, I'll be off with the 7 to take on Spa Francorchamps for an exhilarating track day! So this dyno session was to quickly test and tweak a few things on the setup.
Its no garage queen and gets driven on the regular. Still needs a good clean tho! lol
My predictions were it would make 1. 380 rwhp at 1bar 2. 440-450 rwhp at higher boost.
The results were mind blowing and the overall efficiency of the entire setup surpassed my wildest expectations.
It made: 1. 400 rwhp at 1bar - super fun and still rapid on the streets! 2. 500 rwhp at 1.5bar - Scary AF!!
In all fairness, I was expecting only 450rwhp but what I achieved was waaaay beyond expectations. I'm well chuffed with the below results on a baby 13B street port and a G35 turbo! I guess Tim's street port flows exceptionally well!
Drove away from the dyno in one piece without issues and it looks like the new 50/50 meth mix is working really well. The entire package is cohesive and works really well as a single unit. I did not push beyond 22psi as I was chasing 450rwhp....but ended up with 500rwhp.
I am looking forward the upcoming SPA track day next week. The road trip I've planned in the 7 is over 1,500 miles and I cant wait to start this journey. Hopefully, i'll be able to get a few draggy runs in on the new high boost setting.
just making sure that you recognize that 1 liter of 50% meth/water mixture is 0.56 liter methanol and 0.44 liter water
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By weight or volume? haha
*Was hoping for a little roast by rx8, but honestly never thought about that.
SDS usually lists concentration by weight, but there isnt really a "standard" here, is there?
Isn't ethanol pump fuel ratio based on volume? How about Coolant? Premix? I'm genuinely interested.
*Was hoping for a little roast by rx8, but honestly never thought about that.
SDS usually lists concentration by weight, but there isnt really a "standard" here, is there?
Isn't ethanol pump fuel ratio based on volume? How about Coolant? Premix? I'm genuinely interested.
If you want a proper 50/50 mix then you should do it by weight. At least that's the old wisdom from forever ago. As rx8 pointed out, when you mix by volume it ends up going slightly heavy to the meth side.
I'm half tempted to just use straight water when I finally get my FD back on the road just to avoid the headache and hassle of mixing.
so if you mix 1 gallon of each for convenience you end up with about 56:44 water:meth ratio which is better as far a knock prevention due to the slightly richer water mix
yes, but I’m more aligned to the fendamonkey approach of water only, but with atomization, nozzle placement, and fuel type considerations, in addition to another factor or two relative to my personal focus being mostly short-run autox use. The same factors would apply for 1/2 - 1 mile speed runs, but for competition reasons some things might be better left unsaid.
Which I can understand why some people may choose to focus more on unique spark plug designs and such given the pre-ignition consideration for higher methanol percentages. I might suggest that some of the results and conclusions on the forum wrt E85 use may possibly be skewed due to meth injection rather that water only. With gasoline fuel, meth is a consideration, but if using mostly alcohol fuel then you might want to ponder on whether methanol in the mix might be necessary or not.
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Dyno gurus, Dyno operators/ experts...have at it...is it whp or not?
The shop advises SAE smoothing 5 is the most accurate for all their builds and this dyno....I have no idea if this is true or false.
For the American crowd they also did a correction for STD smoothing 5, which made a bit more whp!
I've had a couple parties dm me on insta advising its not rwhp...because of math...5252 power/torque and this is just power at the flywheel. I said ok thanks....
I checked with the dyno shop and they wont have it and advise all their supra builds are reported in whp for this dyno. I said ok thanks...
Power and torque for a G35-1050 at 22psi and 14.5psi.
Some says its 400hp and 500hp and others say its 400rwhp and 500rwhp. I'm sharing the dyno grahps so full disclosure from myside.
Most that know me....understand I couldn't care less about dyno numbers and the only thing that matters is how fast the car accelerates in the real world from 100-200kph.
I will test on dragy soon and report back. If i get in low 6s range....its more than likely on the balance of probability near 500rwhp. However, if i'm still stuck at the mid to low 6.5 100-200kph....then we will know the numbers are not whp...even though the dyno operators swear by it.
Place your bets...
Last edited by rx7srbad; Oct 13, 2023 at 08:07 PM.
They seem to be accurate - though visually skewed - numbers. I'd never give a client a dyno sheet with different scaling on horsepower/torque though, but thats just me.
Dynos are for quickly finding gains & losses while tuning or troubleshooting, I wouldn't worry about the 20hp difference between the two scaling factors. I agree the chart would be easier to read if the torque and HP y-axis scaling was set the same. I'd also change the AFR scaling to be 10-14 AFR (or even 10-13 AFR since most cars shouldn't see anything outside that range during a full-throttle run), then make the AFR plot less tall so you can make the power plot taller and more useful. Dynojet brand has a reputation for sometimes reading high (rarely low) compared to other brands, but they tend to be consistent. Mustang brand dynos have a reputation for reading low, Dynapack tend to read high, and there are plenty of other brands that I'm not familiar with. IMHO your dragy results are much more useful for showing how well the car performs than comparing dyno sheets.
I did some digging for dyno sheets on the G35 or the older GTX3584rs on 13bs. From what I have found....dahm made 550hp on a stock port with a gtx 3584rs at 31psi. He again made 630hp at 31psi on a G35-1050 1.21ar. 10psi more than my results.
Omar from race only also shared some data on his insta per my request on a GTX 35 which made 554hp at 25psi. On the balance of probability....perhaps the dyno jet is reading upto 17% higher but the dyno operators swear by it being whp. So again the draggy results should spill the beans if its hp or whp!
I've not tested this new high boost setting for the 100-200 runs yet and i have no idea how its going to perform! Either way i'll share when i complete 5-10 verified 100-200 runs.
Dynojet chassis dyno output is always quoted as wheel horsepower in the U.S.A. since it was measured from the tire interfacing with the chassis dyno drum.
However, if you look at the formula Dynojet uses to measure the work done by the tire in accelerating the mass of the dyno drum you will find they used a fudge factor to provide a HP number closer to the manufacturers claimed crank HP.
This is why we say USA horses are a little smaller than other horses when measuring HP.
Other brand dynoes often include a mode where actual work output is accurately reported. Dynojet does not include this mode.
Hi Steve, thanks for sharing mate. Look forward to the results. Take your time and if you can also get a 60mph-130mph run if possbile. If you're using the stock FD trans, if you rev out to 8krpm in 4th you should be able to get both 100-200kph and 60mph-130mph. This will be a really good result to have.
@rx7srbad finally got a draggy run.. it’s a 60-130mph
This is on E65 at 22psi with boost tapering down to 20psi by redline.
I need a more free flowing exhaust.
It’s a large street port, 8374iwg, rotary works v-mount, 3” exhaust.
No dyno, just street tuned by me. #garageguytuned
The car feels great instantly spools, great street turbo!
But I really don’t think there is much more left in this turbo though.
I did some digging for dyno sheets on the G35 or the older GTX3584rs on 13bs. From what I have found....dahm made 550hp on a stock port with a gtx 3584rs at 31psi. He again made 630hp at 31psi on a G35-1050 1.21ar. 10psi more than my results.
Omar from race only also shared some data on his insta per my request on a GTX 35 which made 554hp at 25psi. On the balance of probability....perhaps the dyno jet is reading upto 17% higher but the dyno operators swear by it being whp. So again the draggy results should spill the beans if its hp or whp!
I've not tested this new high boost setting for the 100-200 runs yet and i have no idea how its going to perform! Either way i'll share when i complete 5-10 verified 100-200 runs.
try and do 60-130 runs. More appropriate to compare with the people of murica lol
I will be out at the drags next week and I will get some 60-130 times on my 2 rotor car.
@rx7srbad finally got a draggy run.. it’s a 60-130mph
This is on E65 at 22psi with boost tapering down to 20psi by redline.
I need a more free flowing exhaust.
It’s a large street port, 8374iwg, rotary works v-mount, 3” exhaust.
No dyno, just street tuned by me. #garageguytuned
The car feels great instantly spools, great street turbo!
But I really don’t think there is much more left in this turbo though.
@rx7srbad finally got a draggy run.. it’s a 60-130mph
This is on E65 at 22psi with boost tapering down to 20psi by redline.
I need a more free flowing exhaust.
It’s a large street port, 8374iwg, rotary works v-mount, 3” exhaust.
No dyno, just street tuned by me. #garageguytuned
The car feels great instantly spools, great street turbo!
But I really don’t think there is much more left in this turbo though.
Steve
Hey Steve, thanks for sharing some great results. if you have a look at your draggy app and change the unit to km/h you should be able to get the 100-200kph report. Can you post that as well?
I'll add it to the leader board.
try and do 60-130 runs. More appropriate to compare with the people of murica lol
I will be out at the drags next week and I will get some 60-130 times on my 2 rotor car.
Sounds good and will get some 60-130mph runs in soon.
It's been cold and wet this side so not much opportunity to test safely. Went out a few days ago and in 3rd flat the rear stepped out immediately at low boost which is 14.5psi.
Finally a Draggy
