Cost-effective performance modifications: What can i do?

[UNV-323]

The following is a common question thats asked here...so lets make an example of it. The basics apply to any Astina.

cheers
Dan/rupewrecht

Hi i really wana start modifying my car but money is the main problem. What can i do to my engine that would be cheap or even free. U know, some DIY jobs. And whatelse should i do to my engine that will cost me a bit of money. its a 93 Asinta 1.8 SOHC. Whats the go with the inlet to the airbox that comes from nowhere. its a sealed piece of ****...??? goes into the side of the airbox. So yeah could u guys please give me a big list of anything i can do to my engine and prices if possible. PLEASE!!!!!
okay thanks peoples! :D

[MrShadow]

Check this topic out:

http://www.astinagt.com/forum/viewtopic.php?t=625


basically, the cheap(ish) ones are:
1) Cold Air Intake
2) Exhaust
3) Advance timing (will mean running Preimum Uleaded)
4) Sports air filter
5) Better spark plugs/leads (?)

To the mods (Rupe and Lantis) ==> Can we make the above topic sticky? We've had numerous questions on cheap performance boosts in the last few months. Mabey also rename it to something more meaningful.

[Tony]

Drop in a K&N air filter - $100
Fit a performance muffler - starts around $150+
Use 98 octane fuel - hovers around 94c a litre up.
Use a fuel additive/upper cylinder lubricant like Morreys - $18 for a big bottle that'll last months.

[Rupewrecht]

Also, a rising rate fuel pressure regulator (in conjunction with filter and exhaust) will improve performance. Anywhere from $250-400 depending on brand

what it does is supply more fuel (only when you put your foot down) by increasing the air/fuel ratio from 1:1 to 1:1.7, therefore putting more fuel into the combustion chamber and enabling you to go a little faster :wink:

[Tony]

What rev count does the regulator kick in? Does it benefit the low end or really just the high end?

[Rupewrecht]

the RRFPR works constantly, but really only supplies any extra fuel when you put your foot down. It replaces your existing fuel pressure regulator.

http://www.astinagt.com/forum/viewtopic.php?t=771&highlight=fse

[ezin]

Uz r amusing!
A RRFPR is used on turbo cars only!
A normal pressure Reg works via manifold pressure! The more negative pressure "idle" the less pressure in the fuel rail! (30-35psi) Then when u full boot it there is very little vaccum! Causing the diaphram in the reg to flex & cut of more fuel going back to the tank! Thus more pressure (40-45psi)
A Rising rate Reg is only used in high boost applications! When the engine is leaning off and you cant open the injectors any longer! Its just so u can get more out of an injector!
If ya ask me its a waste of money! Wait until the engine is leaning off to buy one!
Go to Jaycar to get a cheap mixture meter that patches into the original o2 sensor! Or u can pay heaps for a Gauge!

[Rupewrecht]

A RRFPR is used on turbo cars only!

i disagree. it can be used on any efi car, but is of most benefit on cars which require more fuel than standard - like turbos OR worked NA hondas etc

[ezin]

LOL!!
Yeah only if the car is leaning out!
Otherwise your just emptying your wallet!
+ you can get a bosch adj pressure reg for cheaper!
Or even better, go to a volvo wreckers & rip one of the old ****ers! Fits in the pocket nicely so the price is right!
Dont forget about ur poor old fuel pump!
DO a flow test (AT pressure) first! U might need a new one!

[BigMal]

Ezin,
You ever heard the term Tip-In. Its all to do with the initial
opening of the butterfly and the extra fuel added at that point
and how it affects responsiveness. Much like a powervalve in
a holley Carby. Having a FPR which increases the pressure
increases the Tip-In and increases responsiveness. Its effect
after that is reduced as the O2 sensor reduces the pulse width
to try and keep the mixtures right. I have not recomended one
as a good economical upgrade but on the grand scheme of
modifications is one of the cheaper ones and does have a positive
effect on performance. No need to slam people.

Mal

[ezin]

Not slaming Man!
Just ofering an opinion that might not have been considered!
The more we know, the more we can make beter informed decisions!
I dont know anyone in here! and dont know there level of expertise! So im just stating at the basics! Maybe it might help, maybe not! As long as we all find somthing to make our cars go hard its all good!

[Cosmo Dude]

All opinions are welcome.
When there are different viewpoints new ideas blossom. Good to be challenged but not to be flamed.

Rod

Philosophy leason over

[BigMal]

Uz r amusing!
A RRFPR is used on turbo cars only!

LOL!!
Yeah only if the car is leaning out!
Otherwise your just emptying your wallet!


Maybe I am taking these a little out of context as they sound to be
challenges to me and not just opinions. Seeing I dont know you will
accept you didn't mean to slam. I'm just one for sticking up for my
mates.

Regards

Mal

[ezin]

No Drama's Mal!

Im not a ****ing english teacher so some **** is bound to come out wrong!
Im just going on the info from all the courses ive done man!
If it helps any of u guys, then im happy!

[Toyboy]

Just a suggestion here aswell man,just try keep the swearing to a minimum :wink:

[ezin]

Sweet!!

[globalautomotive]

Traditional mechanical educators were the first to say... 'You need fuel' just change the fuel pump, or increase the injector size.' Old school...

So push fuel harder against the same fuel pressure regulator resistance and the same injector size to increase overall fuel delivery throughout fuel curve.. Or increase the cc rating of the injector so as to provide more fuel, again throughout your entire fuel curve. No tunability whatsoever..

Why not regulate what you have until this is not enough. This will depend on how hard you go power wise, although it's definantly the 'new school' way of modifying intelligently. The fuel curve is raised throughout the entire rev range to match the air flow characteristics (so you get your mixtures correct), and the additional 1:1.7 means that on throttle your responsiveness is about twice as fast, so your fuel system gets to where its supposed to be twice as fast. Like I mentioned in the FPR post over the road, 'the slowest thing to respond in an efi system is the FPR' and this is no accident. This was done to prevent an engine that was annoyingly responsive for the rest of society that do not want to race at the lights. :lol:

The thing with RRFPR's is when you adjust them at idle to stoiceometric mixtures required, it will only supply fuel when you thump the foot. What other fuel based mod can supply you fuel when you need it although remain steoiceometric when you don't? None. The advantage, drivability and max fuel economy.

Suggesting that a Adjustable RRFPR is only for Turbo Charged vehicles is like saying that a mandrel bent 3" exhaust is only used on Forced Induction applications.' At some stage of modification the engine will need additional fuel. The factory fuel system is rarely designed to be put to the test from a performance perspective.

Ezin. Your text regarding how a fuel pressure regulator operates is correct. But to suggest that only a forced induction car will require is not correct.

As vacuum drops - fuel pressure increases. To explain it clearly, at idle vacuum is at it's highest. As engine speed increases, vacuum pressure falls and fuel pressure rises. Why? Because FPR are vacuum/boost operated. The Vacuum line that runs to the top of them are controlling a diaphragm which connects to a shaft that blocks the return of fuel back to the fuel tank. So at idle when vacuum is highest it will hold the diaphragm/shaft back to allow more fuel to pass.

Acceleration :arrow: less vacuum :arrow: more fuel pressure.

Additional fuel is only required on fuel systems that are lacking.. or engine lean out issues.. True. Additional fuel is not going to provide power unless there is uncombusted O2 in air to be used. What Ezin is suggesting is that a NA car will never reach a point where it has uncombusted O2 and therefore will have no use for a RRFPR. This is not correct. So you have never heard of an NA engine running lean?

What I can say is that a forced induction vehicle has one additional benefit to the NA.. Boost pressure can be increased to higher levels and the factory fuel pump/injectors will cope. With this in mind the power advantages are certainly greater.

At Wide Open Throttle (WOT) whether a forced induction or NA, fuel pressure will be the same.... whatever that spring will hold against the maximum pressure of the fuel pump. Both NA and Forced Induction vehicles have the same problem regarding fuel delivery in higher revs. This has been the problem since the beginning of time. The issue of engine speed and adequate fuel delivery. There is untapped power to be had.

:arrow: As engine speed (rev) increases so does the demand for fuel. What decreases though is the amount of time we can ask an injector to remain open. So how do we supply fuel in higher revs? Fuel pressure forces more fuel from the same duty cycle. We are not talking about heaps of fuel when we talk about 'more fuel.' A little fuel goes along way...

What we have also found is an improvement in 'Atomization.' A slight increase in fuel pressure against a factory injector provided more power than a bigger injector supplied by a factory fuel pump. Why? Because improved atomization (fuel distribution) meant that there was a more surface area of fuel exposed to air. And you know what that means.

Cost Effectiveness? You just saved $150 x4 = $600 or so injectors and $400 for a decent fuel pump. You'll get alot more from your reg for $385RRP. So yeah, i think so. :D

Regards,

[Toyboy]

Well what sort of pressure do you recommend that the BP 1.8L DOHC engine should have the FPR set at b4 it starts getting stressfull on the Fuel pump?
Cause i have been running mine at between 44-46PSI for the last 8 months now :shock: and would like to know if this is to much for my motor :)
I have a K&N pod filter,cool air induction,2 & quarter" sports exhaust,timing running at 14/15deg,and the usual aftermaket leads/spark plugs :P

Cheers :)

[ezin]

Yes! I quite like your answer GlobalAutomotive!
But im at a loss, Please explain!
A normal FPR has less pressure when there is vaccum and more once it reaches atmospheric pressure or boost pressure eg 10psi! But the difference in F/Pressure from atomospheric to 10 psi is the same pressure if measured on a gauge! Eg 44 psi at atomospheic and 44 psi at 10 psi!

I supose it all comes down to the design of the reg, + fuel pump pressure when the line is totally blocked off!

I thought you could by a RRFPR that has a specific rising rate! eg 45psi at 10psi and increases to 55psi at 20psi! Thats going to be usefull on a N/A car isnt it! unless u can cange the rising rate! U must be able 2!!!

[globalautomotive]

Toy Boy, your fuel pressure would not want to be at or over 50psi on idle, although you wouldn't need to get anywhere near that anyway. You would probably find 40psi to be adequate based on you current modifications. Just try turning it down and feel for power loss. I'd say you will probably gain from it.

Ezin, your a cluey guy. I know where your leading with this and Im impressed. Lets see if i can explain this without getting into poo poo.

The diaphrams resistance is the spring. The vacuum holds the spring. When the spring is released it pushes hard. In low performance setup's adding boost will push the diaphram harder against the force of the fuel pump pressure and this may create a slight increase in fuel pressure although the difference is nill to marginal with factory fuel pumps in low boost applications.

On the other end of the scale we have the High Performance Setup's...
In a setup like this the RR FPR has more room to play as it is part of a better fuel system.. It will supply more fuel pressure based on boost in high boost applications because the fuel pumps are considerably stronger than standard. Here the fuel pump fights the spring tension and pushes against the other side of the FPR diaphram in an effort to let fuel escape. Strong boost on the other side of the diaphram will allow fuel pressure will rise. So yeah in this sort of situation you are on the money regarding the relationship between boost pressure and fuel pressure.

Regards,
Adam

[Toyboy]

Thanks Adam,ill turn it down a little and see how it goes :wink: Its just that i was told by some1 from your company when i first purchased it that i should run it at no less than 45PSI if i wanted a decent gain,but i was worried about this and kept questioning the fella i was talking to about whether this would damage anything,and he kept re-assuring me that it would be fine :?
At first he kept saying the Honda boys run theirs at 50+PSI :o But i dont own a Honda engine so how can he compare the 2 to each other :?:
I just want what is gunna be reliable for my engine & other parts,especially the fuel pump :wink:

Cheers :D

[Toyboy]

Well after alot of frigging around/driving i managed to get the reg to stay at 40PSI than went for a thrash,and from what i can feel it actually has lost power now at 40PSI than when it was at 45/46PSI :(
But for reliability reasons i think im gunna keep it at around 40-42max,which will benifit in the fuel department anyway :P

BTW ive had a few problems with the regulator pressure not staying set at 1 setting,Id set it then go for a drive and it would be higher again :? Then id lower it again ,go for a drive and it would be up again,what is causing this?

Cheers :wink:

[ezin]

Thanks for the answer on that one! i thought as much! It is a bit of a sticky question & u answered it well! I look forward to reading ur (LITTLE) bits as they are better than most! :)

[globalautomotive]

Toy Boy.
Don't be worried mate, nothing will be damaged from the additional fuel pressure. To damage the fuel pump it would have to be almost completely blocked off all the time (80psi+@idle), in which case an engine wouldn't run. Injector stick is unheard of these days. Injectors are built too well. But for it too happen geee that would mean alot of pressure behind them. Again your engine wouldn't run at extremely high pressure.

We tell customers that between 30-50psi is the reference points they should work between, because there is no way of knowing what sort of air flow they could have got out of their other mods. When a customer seems concerned about engine damage from fuel pressure we try to ease their mind alittle i guess. I don't want customers to have the perception that they should be concerned about engine damage by playing around with their fuel pressure.

ADJUSTMENT.
When you adjust a FPR, you do so at idle on a warm engine. Ensure that the auto choke has finished operating, as a higher rev will mean a different result.

Once you have a bit of a thrash it is not uncommon for the pressure to be slightly different at idle. At idle RPM a particular air flow (vacuum) holds a particular pressure, the relationship is a constant. After a thrash the rev (air-flow) may be slightly different and therefore the fuel pressure will be slightly different. If you set and it changes, then wait until the pressure is back to where you last set it and make adjustments from here. Surprisingly a psi here or there does make performance differences. Work your way up to where you were. You may find that power earlier than 46psi.

Having to set it at 45+ suggests you have got good air flow from your mods, to warrant the fuel supply.

Ezin. Thank you...

Regards,
Adam.

[Toyboy]

Thanks Adam i really apprieciate your information,i think ill leave it at 42PSI for now and see how i go,i might eventually turn it back up cause i know it loved being at 45/46PSI but im trying to cut the fuel costs down aswell :oops:

Cheers :)

[sam_seventyseven]

Has anyone advanced the timing on the SP20? If so, let me know how you went.

[Mr MX6]

If you have a V6 astina
I would like to add that for ~ 2 grand you can have one of the fastest 323 around.. just drop in a J-spec MX6 motor .. it is called a KLZE. .you can get then in oz/locally or have one delivered 2 your door from NZ for ~ 2 grand or less..
and for 2 grand you cant get much better.. it is a 200 HP motor and it just drops in..

[MartyE]

Hey guys,

just a note on the performance thing here, I recently did a driving trip from Tassie (accross on the boat to melbourne) to Nowra, NSW. I filled up with Shell Optimax fuel (which we don't get down here :roll: ) once I got to Albury NSW. The performace of the car was exellent. I got over 200km more outa a tank of juice and not only that, but the car flew. Everything was perfect. The car accelerated like I'd never felt before. It was so good that I run it all the time I was up there. Pitty I'm back to normal premo now!

So anyone out there, give it a go and see how it goes for you.

Its heaps better than the normal Premium Unleaded that can be bought.

cheers 8)
Martin.

[JynX]

Run some octane booster in your normal premium and it will raise the octane level 2pts or so which is similar to optimax.

[MartyE]

Yeah will give that a go. A few petrol station owners are pushing to get it bought in but nothings working as yet.

We miss out on a lot down here!!

Thanks for the advice.

cheers,

Martin

[Mizda_Mazda]

You can also wrap the headers and exhaust with heat reflective tape or header/exhaust tape. Apparently this keeps the exhaust warm and improves flow through the exhaust system.

Also, BP98 or BP Ultimate is similar to Optimax. One magazine said that BP98 has much better properties than Optimax, but they have the same octane level of 98.

[Mizda_Mazda]

Changing your stock radiator to an aluminum radiator will keep it cooler. Also changing the water pump to an electric one will reduce the load on the engine.

Maybe install an oil cooler(if you have a turbo or supercharged car), prob most cars don't need one.

Changing the ingnition system will help high rpms and high power cars. Changing the fuel system seems unnecessary unless you don't have enough petrol going to the engine. A mechanic told me that even with a higher pressure fuel regulator, the injection system will control at best as possible the amount of fuel entering the cylinder. You may be able to force extra into it, but it would be useless unless your engine is lacking fuel. Also there will be greater load on the injectors and if you haven't upgraded them, they may wear out or fail early.

[technofreak]

What happens when you add an octane booster to something like shell optimax or BP98? do you gain the extra 2pts octane? Someone should try that hehe :D

[Cosmo Dude]

What happens when you add an octane booster to something like shell optimax or BP98? do you gain the extra 2pts octane? Someone should try that hehe :D
When you lift the octaine you can advance the timing a little. And yes their is a small power gain to be had.

[Nate]

What happens when you add an octane booster to something like shell optimax or BP98? do you gain the extra 2pts octane? Someone should try that hehe :D
When you lift the octaine you can advance the timing a little. And yes their is a small power gain to be had.

just out of interest i have heard that ultimate is pure 98 octane and optimax is 95 with octane booster to bring it up to 98 so would you ... in theory achieve more octane by adding booster to ultimate rather than optimax??

[Mizda_Mazda]

I think most astina's can feel a gain, it's just better petrol for your car. Bad petrol eats things, like woolies pertrol eats through exhausts systems.

About the octane boost, I think, in theory, it's the same.
Say if Nate is right:
Ultimate 98: 98per litre + add booster (say) 5 = 103
Optimax: 95+3=98per litre + add booster (say)5 = 103

If you really want high octane levels, why not just by 50 litres of booster and pour it into the tank... But i don't think your car will run very well on just the booster.

Also I saw that thing about the electric supercharger in the other thread. Sounds interesting and I looked around a bit and found another one called the e-Ram. I'd get one if it was alittle cheaper.

http://www.electricsupercharger.com

Check the video out.

[platypus]

hmm another fan....

octane boost is that thing starting with e or somthing... i thinks its in red bull too.... bah i can't merember everything

oh and touline.... that stuff is ok , but in huge concentrations (ie a tank) its baaad and detrimental to performance... it should be used as an enhacer....


if you want to gain performance from your fuel, i'd suggest you go to your local hobby shop, and put 2L of aero fuel into the car, witha FULL tank.... any more than 1 in 10 tanks and this could once again be detrimental

[kthl]

What do people think of these "mod chip" resistors?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7924621915&catego ry=42604

[lamby1986]

so is that little ressistor sitting in the end of the plug the mod is it? is that all?
well. currently im not going to waste 2.50 to find out if it does or doesn't work. if i was going to mess around with such things as air/fuel and timing, id want a real computer. but if your game, give it a shot and tell us how it goes.

[BigMal]

Problem with telling the computer the engine is cold is its cold all the time ie when
you are cruising, idling etc so your fuel consumption will increase a fair bit for that little
bit of performance when you actually want it and put the foot down.

[kthl]

Has anyone here actually tried using that resistor in their car? I want to know before going to the trouble of ordering from the US. Or does anyone know any local sellers?

[BigMal]

If its only a resistor wouldn't you be able to buy it locally from like jaycar for $1

[chipa]

It will also certainly change your fuel efficiency. Whilst much more expensive a safer option would be to get something like a unichip, which would alter the tune correctly.

[twilightprotege]

dont use the resistor. have a look on www.msprotege.com for the issues.

[kthl]

dont use the resistor. have a look on www.msprotege.com for the issues.Do you have a link to a specific thread? Or what's the proper name for that resistor? (so I can do a search)

[twilightprotege]

search for "ebay chip"

[kthl]

search for "ebay chip"Thanks for that.