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Intake query


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Morning all, as promised some notes to accompany the graph and my learnings from the day (and there were a lot).

Finally had a long enough period to go play on the dyno. I visited RGS motorsport after quite a long search for the right garage to do this for me. RGS dyno operator is a 20 yr veteran of engine building, manafacture and tuning including most crucially Yamaha, yes he was part of the team who did the development of our engines. Amazing to listen to him regale on the trials and tribulations and largely frustration Yamaha had with Lexus as they designed a wonderful engine Lexus then strangled.... Anyway, i figured this chap was the man to help me with my project.

The only aim I had for this session was to run three standard power runs to set a baseline, not to chase headline figures literally just to baseline for my project. It ended up being much more complex than this and In the end we spent nearly two hours running different scenarios hence if you see the graph we ended up on about 12 runs all in, to gather as much data as possible.

  • Dyno setup - The dyno dynamics dyno is pretty clever it can be set in many different modes, we calibrated and tweaked for some time to ensure all the correction factors for gearing, run down, gearbox type, AFR calibration etc. were at accurate as possible, this took nearly the first hour. Low velocity cooling fan.
  • Car Setup - Ideal situation for us it to run in 6th gear 1:1 ratio. however as they will pull 177mph in 6th this is out of range in a dynodynamics that are limited to 155mph. So the calibrations were done to run the car in 4th, sports mode,manual, full TC system disabled. Bonnet down, engine cover on

After the first three runs it was hugely evident as to why the dyno data on our cars is so conflicted. Over three runs the we saw a range from 359bhp to 406bhp. Thats nearly a 50Hp variation! It was decided that we had to find out why hence the additional work. It was noted on the lower HP runs that exactly where the power stopped climbing about 5500rpm directly correlated with the engine throwing fuel in and the AFR changing, this is well understood so to find out why we fitted a live logged temp probe to the inlet manifold (the inlet air temp logged anyway) and ran another series of three. This provided our explanation. manifold temps are huge (saw a range from 50deg to 90deg) and power drop off was proportional to manifold temp. So with this understood we ran a further three runs with a space between them to allow the inlet manifold cool down to exactly the same temperature each time and the repeatability was superb, power range for the three runs within 4hp of each other. For info we chose a mid-high point in the manifold temp range at 72deg. With a good solid baseline procedure established an as I was already spending more money that I expected I thought why not throw my intake on and have a go see what happens.

The graph I posted shows the following:

PINK - All original airbox, filter intake elbow, manifold 50 Deg

GREEN - First run with K&N, my intake elbow and manifold at 72deg

RED - as per green but with manifiold temp at 90deg

This was super interesting to me. However as we were making up the plan as we went on I didnt add the standard intake system at 72 deg to the graph, apologies.

More learnings were made from this which all goes to improve my understanding. Despite what this graph shows which is a 17.3bhp loss with the modified set up I was actaully very pleased. What it did prove is two things as I had expected. The ECU has two sets of learnings in this instance, a long term 'map' that is more slowly adapted (hence why people say you need to drive for 1000 miles before you will see the true output of any change) and the live data manipulation that occures 100's of times per socond to make sure the car doesnt lean out an blow itself to pieces. Now this may take some following so bare with me...So when we read the graph you can see that the lambda reading for the last two runs (modified) are way higher than that on the standard run, with more variation than was seen in the back to back runs on the standard intake. So the car is using its short term ability to adapt to environmental condition to richen up the mixture, this although at present (due to 0 miles on between standard and modified swap over) shows a power loss it does show that more air is getting through and it is having to adapt. I am hopeful therefore that on my return to the dyno in a few weeks or hopefully no longer than a month the longer term base map will have adjusted and we will indeed see an improvement.

All in all I absolutely loved this experience, to start to understand a car to this level I find fascinating. I hope everyone takes this for what it is, which is just me being nosey and trying to find my own truth, my way however please feel free to disagree, i will take all learning opportunities. 

I've attached a better picture of the printed graph for clearer info.

Dyno 06062016.jpg

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Interesting write up and some nice findings. I look forward to seeing the results next time.

I've organised an dyno day for this Saturday and it's with a place that run a dyno dynamics setup. Not sure what car setup to go with as I won't have the time to get the dyno set up properly since it'll be a case of drive on, 3 runs and drive off.

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This one was set in base configuration either 'Shoot out 8' or 'Shoot 8' cant remember the actual wording but it was an 8. Maybe we should have a dyno thread too? Love to see those results and know the background to each. Exciting stuff.

If you're looking for the big numbers, I can only recommend what I found, warm her right up oil temp at least 3 bars and then let her sit bonnet open for 10 minutes before going on the RR. should gove the best chance

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Cheers. I'm looking for an honest baseline run before the new exhaust is fitted two weeks time. Something that replicates real world conditions ideally so I'll make sure it is warmed up before it goes on. I might just stick with the often quoted 6th gear, sports mode and gearbox in manual. Did you hold down the traction button to switch it off or is there a different method?

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I did, It was a hold down on the traction so fully off both yellow dash light on. Sure your operator will ask but if not it might be worth checking with the dyno operator what the max speed the dyno can take is. It wont hurt anything but your graph will stop somewhere in the high 5000rpm range as the dyno might not read over the 155mph mark. The first guy I was speaking to (at reception) asked me all the questions and if I hadnt have mentioned it he had assumed that as with german cars ours are limited to 155mph.

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The problem is there are a number of variables that can affect the results you get.

I'm guessing you didn't have the bonnet open for your runs (hence the high manifold temps)? Also worth considering removing the main engine cover, as it is well insulated to reduce road noise, but allows quite a bit of heat build up.

I don't believe anyone in the UK has quite mastered the art of dyno'ing the IS-F as yet. We did a couple of dyno days in the past (should be a thread on it around here somewhere), but the first place were utterly useless! :frusty:

Eurospec were a lot better, but we were doing the runs in 6th gear as recommended from our American brethren! :cool:

I guess it would be useful and worthwhile trying to keep these results together on a new thread? We can then start trying to fine tune and replicate as many conditions as possible to get more accurate results.

The dyno operator plays a huge part in this process though. If they mess up the calibrations for the dyno, the results will be way off! :sad: 

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Pete. Totally agree with all your points, I will update my original dyno description to add detail on bonnet, engine cover etc. For me and my project its not really to compare to others just to myself (if that makes any sense) so if I run in 4th and then on my return run in 4th it works all the same. I will however (on my return to the dyno) take one for the team and ask to run one in 6th just so we can make direct comparison. I dont expect any difference however as we spent so long making the calibration and corrections it should be largely representitive. I would like to see a thread on dyno results.

Oh go on then I'll start one :yahoo:

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  • 2 weeks later...

Final revision completed and fitted today. I'll let it run for a thousand miles and stick it back on the dyno see how we go.

Overview

D1052B80-A5F1-4D9C-A058-6E03A004B298_zps

And the re-routed breather to match that of the RR-Racing Setup

2B1DF81A-69D7-45DD-BBDF-257D59A78096_zps

So there we have it, an IS-F CCSR / HPS / RR-Racing mashup intake system. Rather pretty to.

AB43BE2C-68EF-4FB2-9C45-399E44FC9F56_zps

 

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Looks good Dave. :thumbsup:

Think the finish etc for a DIY version is spot on chap. :cool:

Will look forward to reading your further posts after you do the miles to get another dyno run done.

Glad it all came together for you. :smile:

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Of course I would have liked a bespoke one piece silicone item but the price for a one off was of course extortionate. I did enquire and I could get the setup fees waved if I ordered 20 units.... Haha , I don't have much use for 20 😀

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