"Bang per buck" upgrades

[ghanda]

Following on from Ako's excellent and concise Statements, I wonder if somebody could provide me with some answers to the following performance mods, something along the lines of benefits, what it does and expected bhp gains. EG:

Q: 1) De-Cat (£50)
A: lessens restriction in the a part of the exhuast system. c.+15bhp

So, if you would be so kind:

1) 3 RON Octane Booster (£4 a bottle)
2) Dastek Unichip (£500)
3) Profec B Boost Controller (£250)
4) Apexi AFC (£200)
5) 255lph Fuel Pump (£50)
6) SARD Fuel pressure regulator (£50)

7) Items 1-6 combined.

So you may now have an idea of what I have planned
Seriously though, this is my daily driver, but I am looking for a safe and reliable 340-360 bhp atc.
Feasible?
Cheers

[Wodjno]

Following on from Ako's excellent and concise Statements, I wonder if somebody could provide me with some answers to the following performance mods, something along the lines of benefits, what it does and expected bhp gains. EG:

Q: 1) De-Cat (£50)
A: lessens restriction in the a part of the exhuast system. c.+15bhp

So, if you would be so kind:

1) 3 RON Octane Booster (£4 a bottle)
2) Dastek Unichip (£500)
3) Profec B Boost Controller (£250)
4) Apexi AFC (£200)
5) 255lph Fuel Pump (£50)
6) SARD Fuel pressure regulator (£50)

7) Items 1-6 combined.

So you may now have an idea of what I have planned
Seriously though, this is my daily driver, but I am looking for a safe and reliable 340-360 bhp atc.
Feasible?
Cheers

All sounds good Gary.

But you have listed the Dastek Unichip(which we all know works well on the VR4) , but also the Apexi AFC ???
Fitting a Dastek is going to alter your Air already, so what is the point of the AFC..

If you are wanting alter the AFR further than the Dastek.
Wouldn't it be wiser to fit an Ultimate from the start and be able to control everything you want to your gain your own specific results ??

[ako]

Octane booster - Personally I wouldn't be tuning the car so close to the edge as to require this, especially not a road car. Cheap insurance agains some detonation though.

AFC + Chip - as already mentioned, one or the other is needed, not both - though the AFC can let you monitor knock in real time which is of some use.

Boost control - Realisitic 30-40hp there, moreso with tuning.

Fuel pump + FPR - thank god you're one of the people here with half a brain and doing this FIRST, not once the stock pump is hitting its limits. No power gain per se, but lots of piece-of-mind gain, also gives you headroom to get around 200kW @ wheels on stock injectors. Without the fuel pump, your limited to around 180kW.

[bradc]

Looks good, but that Unichip probably isn't needed at this stage, I would go with downpipes and a complete exhaust system. Have you changed the air filter?

[ghanda]

Thanks for the replies guys - so the AFC will provide no benefits (apart from monitoring) if I go for the Unichip?

With regards to the air filter, having read the excellent Autospeed atricle "How to eliminate negative boost" I put it into practice in my Golf - and my best solution was 2 3" pipes feeding directly into the standard air box, which I smoothed out and then replaced the MAF to Turbo pipe with a fabricated ally one. I'll be trying similar with the VR, as I'm one of those who beleives in 'over-engineering' the ingedients to ensure the recipe come out sweet

With regards to the down-pipe, yes, I believe that's now the only restriction in the exhaust (complete Fujisurbo with De-Cat) and have so far only found one manufacturer in Japan.

[Quail]

Thanks for the replies guys - so the AFC will provide no benefits (apart from monitoring) if I go for the Unichip?

With regards to the air filter, having read the excellent Autospeed atricle "How to eliminate negative boost" I put it into practice in my Golf - and my best solution was 2 3" pipes feeding directly into the standard air box, which I smoothed out and then replaced the MAF to Turbo pipe with a fabricated ally one. I'll be trying similar with the VR, as I'm one of those who beleives in 'over-engineering' the ingedients to ensure the recipe come out sweet

With regards to the down-pipe, yes, I believe that's now the only restriction in the exhaust (complete Fujisurbo with De-Cat) and have so far only found one manufacturer in Japan.

Sounds good

The AFC will only be good for monitoring if your using a Unichip. You may aswell just use the AFC for tuning, and spend the money that wouldve been spent on the Unichip somewhere else?

I agree with you on the over-engineering

To be honest you may need a custom fabber to do your downpipes

[ghanda]

Mmm...Thanks so far.

OK, so:

Unichip & Boost controller @ £750 Vs. Boost Controller & AFC @ £450 ?

What would I be getting for the extra £300?

[Wodjno]

Mmm...Thanks so far.

OK, so:

Unichip & Boost controller @ £750 Vs. Boost Controller & AFC @ £450 ?

What would I be getting for the extra £300?

Or Boost Controller and Ultimate @ £750

[ghanda]

OK - you're now confusing me!!

Like the title states - What's the Better 'bang for your buck'?

(For a Non-fiddler, who want's to fit and forget?)

[Wodjno]

OK - you're now confusing me!!

Like the title states - What's the Better 'bang for your buck'?

(For a Non-fiddler, who want's to fit and forget?)

2) Dastek Unichip (£500)
3) Profec B Boost Controller (£250)

Sorry

[AllBeItMine]

you can't really think of it as bang for buck modding when it comes to cars. i know it sounds like an oxymoron but its kinda true.

if it were that simple - then the best bang for buck would be a $30 boost tap to wind it up.

but you have to remember one key thing.

the ecu in your car is programed to do the same thing each day, everyday regardless of what you do to the car and essentially it does this based on one and only one key variable - airflow.

now it is my personal opinion that while the car is great in stock form - as soon as you start modding anything that will effect the amount of air the engine is able to process, the stock maps inside the ECU aren't really that great at adapting very much past the base stuff. i just dont think the engineers put much time into programing the upper and lower limits. And i think thats why we have such an agressive safety cut - commonly refered to as the "boost cut"

so - back to the original argument - bang for buck.

you need to get more air into the engine. but you are handicapped by the ecu and how much it can handle. so even though it doesn't make much sense... here is what i think.

Free flowing exhaust - from the turbos back.
-good supporting mod for allow the turbos to flow more with less back pressure. But - no real gains without upping the boost. spending $800 on an exhaust system for 5kw's is not my idea of good bang for buck. BUT its a very important supporting mod if you intend to go further. A decat pipe in my opinion is a waste of time because it is not the most restrictive part of the exhaust system.

Induction pre turbos.
Dont touch this unless you intend to do it properly. if you replace the stock ducting with a pod filter and not work towards some cold air induction you will lose power. if you do it properly however, you may gain 1 hp. The best thing you can do here unless you move your battery to the boot is get a good K&N insert for the stock ducting as the standard airfilter is about the same size and weight of your average phone book. so bang for buck - keep the original stuff or slightly better - spend $200 doing a proper cold air system.

Boost control.
Now this is interesting. i've had my car dyno'd twice. once running 12psi and once running 7-8. the difference was 139kw vs 149kw's. I also know of one other legnum which was running close to 16psi on a dyno (fuel cut defender) and it managed 162kw's. All three of these dynos were just exhaust, filter and boost control mods. This enforces my argument about the stock ECU not knowing what the hell it is doing with fueling and ignition when more air gets forced into the engine. This is futher confirmed by Mr You See who is currently enjoying 205kws at only 10psi. So in short, unless you are going to do something about that fueling problem dont touch it. changing the boost is essentially a waste of time. BUT. if you are going to do something about the fuel control - then you can't beat a good, simple and fool proof electronic boost controller. As previously stated - the profec range are brilliant. they get a tick in the box as far as bang for buck goes.

So essentially - those are the first three typical (power up) mods out of the way - its what i had done, its probably what a few of you have done. and basically it didn't work. did this to my car - cost about 1500 all up having it done. and i gained 10kws at the wheels. if the car was an evo, or a silvia or a skyline i would have seen 40kws by now at the very least - but we are just not lucky with our vr4's

But - what i had now was a good platform.

enter - fuel and ignition management.
So you have a range of choices here. a couple of good options that are pretty popular on this forum are the emanage blue or the safc. both piggy back systems that are relatively cheap to install and quick to tune. You can now tell the ecu what to do! this is where it all happens. If you have your platform sorted you will be able to up the boost. around 10-11psi should be more than sufficient. then you will be able to taylor the fueling to suit. There are a couple of things to consider at this point.

how far do you want to go?
the car will put 190kw to the wheels all day without changing the fuel system. The turbos will also be more than happy at this level.

i would say that 190kw at the wheels is as far as i would go with "bolt on" mods (excluding nos) before i would seriously re-think the strategy.

if you want to do more than this then i would recommend more than just a piggy back ecu to control the fueling. which means the freedom to remove the MAF and not be limited by how far you can bend the airflow signals. So running bigger injectors, adjustable cams, etc is no longer an issue.

i got to say - if you were looking for bang for buck modding and hoping that every dollar spent was going to give you a significant gain - these just aren't the right cars for that job. its something i have learnt over the last 3 years. but i will say that if you invest a bit of money in an 'overall' improvement - then yeah, they are great cars.

[ako]

*great big huge pat on the back for andy for finally spelling things out to a great number of people*



<-- ABIM gets todays "explaining the facts of life to a lot of VR4 owners" award from me

[Wodjno]

Err Yeah.. I'm sure most people actually realise most of what has been said..

But if you got £750 to spend What you best spending it on first, with perfomance in mind !!

I think this is the question here

[ghanda]

Well, yes and no actually.
I think more than anything the point is how far do you want to go? Having sunk 5 years and over £30K into my Golf (and having had the Engine blow up 3 times on me) I consider the VR as my reliable car

One thing I'm still not sure of though (and thank you all for the excellent amswers):

The difference between an AFC and a Unichip?

Cheers

[ghanda]

Oh - and the exhaust header and some other bits:

http://babelfish.altavista.com/babel...5%2fp%26p.html

[AllBeItMine]

Err Yeah.. I'm sure most people actually realise most of what has been said..

But if you got £750 to spend What you best spending it on first, with perfomance in mind !!

I think this is the question here

and i think i answered it.

exhaust, induction, boost control and fuel control.

i wouldn't worry about fuel pump or regulator. keep it under 190kw.

i would personally recommend the safc over the emanage or unichip - but thats just a mix of personal preference and a bit of chinese whispers about the lot.

if you can get all that kit done over there for 750 pounds (if thats teh budget) then i say thats pretty good bang for buck.

sorry i dont know what previous mods have been done to Ghanders car.

[ghanda]

Nothing - It has a de-cat and a Fujisurbo exhaust. I'm looking for a safe and reliable 340-360bhp (260Kw atc) and am coming to the conclusion that aprt from induction and exhaust, the Boost controller + AFC would be the better option than the Boost Controller + Unichip - the extra £200+ for the Unichip wouldn't give me anything more would it? (If anything I'd loose Air/Fuel graphical monitoring)

Also with regards to the fuel pump and FPR - Surely, for the sake of £100 total, this would be a wise precautionary move?

[bradc]

for only 100 pounds it is quite a good investment, it's definately better value than the unichip, and will let you go further in the future.

ABIM, great post. Freddy's car got 182kw ATW, that is with a Mines ECU, exhaust, and boost at 16psi max, but 12.5psi at max power.

I think Uc's car has so much power because of the replaced tubing throughout the engine, imagine a pressure of 10psi going through a drain pipe, rather than 16psi through a straw. I think that would account for a good 10kw more with a good tune.

[WildCards]

So...£750 spent wisely will take you to 340bhp? Or just put you on the right path?

[bradc]

With the mods we are discussing here, I would guess you would be looking at 330-340hp, remember though it is always kind of difficult to guess how much power you have at the engine, it is always more accurate to measure it at the wheels.