Jump to content
SAU Community

Recommended Posts

I get lots of PM’s (every day) from guys with engine tuning problems. A large % of them are from guys who don’t want to spend the money on a tune when they haven’t finished the mods. They are part way through their list of upgrades and only want to get their car tuned once, when it is all finished.

What I tell them is that there are sacrifices that they have to make, put up with less than 100% performance, live with the misfire, tolerate the lousy fuel economy, don’t use full throttle, watch the knock readings all the time, etc etc. They are the facts of living with it untuned, there is no escape from them. Otherwise the mods aren’t working and money is being wasted on them. That it runs worse, is in some ways a good sign, if it runs perfectly then maybe the mods aren’t doing anything.

The problem is a badly running car decreases the enjoyment, a lot. A nicely running car is a joy to drive, by trying to save money they are reducing that enjoyment down to a lower level. Plus they are wasting money with poor fuel economy and in many instances doing permanent damage to the car, not just the engine, but the perhaps the clutch, the gearbox or the diff.

So think carefully about your modifications, the order in which you do them and most importantly the budget you are going to spend over the timeframe that you choose. Then talk to your tuner about your plan. Most of the tuners I deal with are very receptive to repeat business and give price and quality of service advantages to regulars. They want you to come back a few times, they want you to talk to your mates over time about how well your car is being tuned. Their business mostly lives and dies on word of mouth, so a guy who gets his car tuned once only then goes away, is not as good for their reputation as a guy who regularly sees driveability and power increases.

The big advantage of using a tuner more than once is that they get to know your car and you, what it needs and what you like. People who drop in out of the blue, say “tune my car” and piss off, never to be seen again are hardly going to get as good a tune as someone who has been there before. The tuner knows the car, its mods, has the previous dyno runs and, most importantly, knows what the owner wants from it.

In summary, do the usual exhaust, filter, intercooler upgrades and turn the boost up a couple of psi or so. You most likely won’t suffer too badly, although fuel economy will be crap. But once you start slipping on that bigger turbo or adding a few psi of boost, larger injectors, bigger AFM, adjustable fuel pressure regulator etc, then you need to seriously think about getting it tuned. Even if the mods list isn’t fully ticked off.

:( cheers :(

Link to comment
https://www.sau.com.au/forums/topic/164361-delaying-the-tune/
Share on other sites

I do agree, but then again, I'm in the 'middle' stage just as you have described.

Had the turbo done recently and 'want' a retune.....but,

I don't suffer the bad fuel econ. or misfiring, it's just not on FULL potential.

Very soon i will have fuel pump/injectors/AFM and most definately will be paying for a FULL retune.

I'm quite happy to commute every day on low throttle and lose out on the full potential.

I know it's coming and I'm a patient man.

Also, i went back to my original FC tuner (rang him anyway) and said that i wanted the new setup to be tweeked to match the new turbo....New turbo being the only change.

Pretty much full price again.

I can't afford to pay that twice.

Details were :

Original - FMIC/Pod/Zorst/Power FC on 12psi (194rwkws, the usual for R33)

After - Same as above with HKS2535, wanted 12psi there too, does that warrant a full tune again? ..asking as i really don't know but would have thought that 70-80% of the work is already done????

Result - So now on 10psi and low throttle with no change to tune.

what are your thoughts on road tuning gary (or anyone else for that matter)?

my mechanic is a complete gun... gets the job done well, has the patience and attention to detail i've yet to find in other mechanics, but absolutely hates dynos. reason being is that he thinks that it doesn't simulate regular driving conditions as much as being on the actual street.

what he does is throw in a wide band and take it for a "drive" and tunes it on the go. i've seen his road tunes on a 3rd party dyno, and his afr's are dead on perfect and almost always quite a linear power curve. he likes to tune cars with a more progressive power delivery. i don't exactly know how he does it... but i've yet to hear a single negative thing (problem) out of all the cars that have gone there.

obviously on a dyno you can watch everything, and have numerical figures to confirm and diagnose. so again what are your thoughts on this kind of tuning?

It really depends on the tunner.

Persoanlly I use the dyno to get the tune good. then take it out for a drive to tidy up any loose edges and make sure its still aceptable and not pinging on the road.

Im sure sydneykid will agree RB26's are notorious for pinging their brains out on the road despite the fact they behave themselves on the dyno.

The dyno is nice to use as you can review AFR's across a power run but with decent logging you can do that on the street as well.

Another little touch is to drive to the vehicle with the owner after the tune and address any driviability issues they may have straight up. Again I drive the vehicle different to the next guy and he may notice something in the way it drives that I didnt.

Or you could do what im doing.

My first list of mods was your typical bolt on stuff ie: cooler,boost controller,dump pipe ect ect.

Then when i purchased the Power Fc i got the car tuned.Car runs good with no missfire or economy issue.

Im in the "second phase" of upgrades,just got a VG30 BB highflow,Profec B,Z32 AFM and poncams and Nismo injectors will arrive in the coming weeks.Once i have all the parts ill be taking the car to a tuner and getting all the mods and tune done at once.

1) It will work out a bit cheaper

2) Wont be worried about my car running rich/lean while driving it untuned.

3) I think its more rewarding to see your power level increase by leaps and bounds rather than spend a few hundred dollars on an upgrade then only seeing it only produces 5-10rwkw more.

Also there are things you can find on a road tune that you cant on a dyno.Ive had two FC tunes so far and both of them had high knock readings at some part of the rev range.These were dyno only tunes.Next tune will be a $900-$1000 job as i want my tune perfect for the setup ill have,mainly because ill be leaving the engine mods alone for a bit to concentrate on brake,sus and diff.

IMO :thumbsup:

what are your thoughts on road tuning gary (or anyone else for that matter)?

my mechanic is a complete gun... gets the job done well, has the patience and attention to detail i've yet to find in other mechanics, but absolutely hates dynos. reason being is that he thinks that it doesn't simulate regular driving conditions as much as being on the actual street.

what he does is throw in a wide band and take it for a "drive" and tunes it on the go. i've seen his road tunes on a 3rd party dyno, and his afr's are dead on perfect and almost always quite a linear power curve. he likes to tune cars with a more progressive power delivery. i don't exactly know how he does it... but i've yet to hear a single negative thing (problem) out of all the cars that have gone there.

obviously on a dyno you can watch everything, and have numerical figures to confirm and diagnose. so again what are your thoughts on this kind of tuning?

the main issue with on road tuning is you cant hold a specific rpm / speed and load it up

and you have to deal with traffic / road rules,ie you cant just do 160kmh to shift the car around on the map to touch up areas

but the street is defeintely required for light cruise and some extra touch up. ive done mine with a wideband sensor

did a fair bit of ign touch up and cruise afrs. drive in 3rd gear at 30kmh, 3rd @ 40km, 3rd @50kmh etc etc.

You cant legally road tune a car. Simple.

3rd see's well over the posted speed limits.

So if you head to a track, your stuffed.

Best to do it on a dyno, and then if there are issues driving around on the street, have the tune adjusted where its a little off. As you cant really replicate all situations on a dyno. You can get it pretty close, sometimes spot on. But sometimes it might knock in one or two spots. Which is a 5-10min fix :thumbsup:

Thats the exact approach I use Nismoid. I agree its really dumb road tunning a car fully, and anyone who has done it for a living will agree. I know several tunners who I deal with who began tunning cars on the road and now have moved on to use dyno's and run their own tunning shops.

Im personally a fan of road tunning rotories because they are to easy to go bang on the dyno!

NYTSKY there really is no need to fork out that sort of money for a full tune anymore. There are places that still promise the earth when it come to tunning a Power FC, they charge through the nose and deliver a far les than satisfactory result. You have already experianced it yourself.

The way the tune it finished off gives the biggest impression to the driver. Any one car tune a car to a flat 12:1 on a dyno at full noise thats easy, but it takes more to tune a car seamlessly.

  • 1 month later...

Is there any risk of "over-tuning"

Well not over tuning but isn't dyno time the most stress that will be put on the engine etc?

I have put my car on the dyno to be tuned 3 times this year (twice for upgrades and once to try and fix some problems).

Is it best to try and stock pile as many mods as possible and put as many on as you can then have it tuned until the next pile of goodies is ready to go?

A mate of mine said if I keep putting my car on the dyno it will go bang soon and I need to make up my mind exactly what I want and then stop. A rebuild enigne is on my "to do" list but I want to do this in my time, not because I have to.

Cheers

Myths like running a car on the dyno will reduce its life by 10,000km's and so on are nothing but fibs and furphies.

When you think about it, briefly winding the car out in 4th is not out of the cars limit :)

Would be no different to drag run really.

Myths like running a car on the dyno will reduce its life by 10,000km's and so on are nothing but fibs and furphies.

When you think about it, briefly winding the car out in 4th is not out of the cars limit :thumbsup:

Would be no different to drag run really.

But don't drag cars get rebuilt on a regular basis

Car enthusiasts don't risk the health of a motor for no reason, its almost always $$$ related.

As already mentioned on here, its tuners that charge $1k for a full tune on a PFC, and 400 for a "touch up" that make people more content to hang on, and wait till they get [insert here] until properally tuned.

--

Edit: Realized i only ranted the hassles :/ I totally agree in finding a good tuner, to help progress the development of your setup. Although it can rack up the costs a little, your not always going to get charged that same amount for touch ups ;) I think one should try to tune the best combination out of each specific setup; it would give the best comparison of "which mod changed which feeling" which builds a better a understanding. Remember, a smokey farting, stalling import, isn't what its all about.

---

Dyno more abusive then the road is a crock. WOT at a constant RPM while tuning a load point maybe, but i would think having wind resistance, and a constant 70% throttle position in 4th gear up a slight hill would constitute more "time accumulative load" or "engine damage"

Edited by GeeTR
Is there any risk of "over-tuning"

Cheers

Many dozens of WOT high load tuning runs might have some negligible wear, but the majority of time i would say, is spent on low load spots, getting drivability just right… which would have virtually no wear

my 2 cents

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
    • Nah, that is hella wrong. If I do a simple linear between 150°C (0.407v) and 50°C (2.98v) I get the formula Temperature = -38.8651*voltage + 165.8181 It is perfectly correct at 50 and 150, but it is as much as 20° out in the region of 110°C, because the actual data is significantly non-linear there. It is no more than 4° out down at the lowest temperatures, but is is seriously shit almost everywhere. I cannot believe that the instruction is to do a 2 point linear fit. I would say the method I used previously would have to be better.
×
×
  • Create New...