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  #1  
Old 11-16-2006, 08:23 PM
ahmed-abrar ahmed-abrar is offline
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tuning options

hi, r there any methods increaseing performance at reasonable costs outher?
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  #2  
Old 11-17-2006, 02:57 AM
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Performance hike?

Quote:
Originally Posted by ahmed-abrar
hi, r there any methods increaseing performance at reasonable costs outher?
Hi Ahmed
The short answer to this is No, but it largely depends on what your definition of "reasonable" might be.

The engine is already in a middling high state of tune for what it is, so the normal tuning route of changing to hot road camshafts and cleaning up the inlet and exhaust ports, these will not yield major horsepower upgrades. Part of your cost problem, there are four camshafts. So changing or re-profiling 4 of them is expensive.

This is not saying it can't be done. There are very long [and informative] threads about this, some of our American guys are working on it right now. If you do a search for all posts by Need for Speed, you will find the information and the progress. I'm taking a wild guess into the unknown here, but I would expect head work and re-profiling work to bring HP from 225 to maybe 280, possibly more. No idea on cost, but it would not be cheap with the work involved.

The other route is forced induction. Graham, F1SVX, has fitted a supercharger to his car. Power gains depend on how many pounds induction pressure you use, and what other mods you make to support it. Around 300 engine hp is relatively easy, 400 is not extreme, but needs many things changed which will hike up the overall cost.

If you want bolt-on power, and you have a friendly bank and a good mechanic, you would do worse than look at the supercharger modification by Longassname, Michael at Ecutune: http://www.ecutune.com/svx-stage3.htm

The whole kit costs $7500, which I reckon is about £3900 of your money. Plus you will have to fit it, and there will be shipping charges. But for the money, you will get REAL horsepower!

The only problem I see is you would need to want a very powerful SVX very badly to spend this kind of cash. For the same money, you could probably buy either a Toyota Soarer 2.5 TT ex Japan, or a Nissan Skyline 2.5 Turbo, or a Toyota Supra 3.0 Turbo. Any of these will give you similar horsepower just for turning up the boost, and more if you spend money.

It's a money decision, really, and one about what you want to end up with when you have spent it.

Joe
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Old 11-17-2006, 04:41 AM
ItsPeteReally ItsPeteReally is offline
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Yes, I'm afraid that Joe has it about right, there is no cheap, easy, way to make the SVX perform significantly better.

There are several kinds of things that you could consider, they are :-

1. Increasing the engine's power output.
Forced induction seems to be the only way to get a significant increase in useable power across the entire rev range. I am of the opinion that other induction or exhaust modifications may offer only insignificant gains, and may actually be worse than the stock set-up.
Whilst reprofiled cams may give you an increase in power at the top end, this will almost certainly result in worse performance at lower speeds. The latest Subaru developments in variable valve timing technology offer a possible way around this problem, and it is a shame that the latest 3.0 litre cylinder heads are not a simple 'bolt-on' option. But adopting this technology is something worthy of future consideration

2. Decreasing the parasitic losses in drivetrain.
Basically this means swapping over to a manual gearbox, should get you another 10% or so more power to the wheels, and give you a much more 'involving' driving experience.

3. Reducing weight. The SVX is a heavy car which is bound to make it feel a little sluggish. If you could reduce it's weight by 20% you could transform the performance of the car by making it much more accelerative. Potentially, these gains could be free of charge, as it might only involve removing stuff. The problem is that to lose 20% of the weight you would have to throw away 700 lbs! If you can find 700lbs to throw away you are on a winner. Otherwise you have to spend money replacing the Subaru 'built for a tank' version with a lightweight replacement.

4. Reducing aerodynamic drag.
The standard SVX has a drag factor of 0.29, if you could reduce this by 20% to 0.26 you would liberate a lot of power at higher speeds. I believe that this is not impossible to acheive at low cost. A full undertray would undoubtedly help greatly, the problem is mainly one of measurement; to verify that any changes do, in fact, help.

5. Improving chassis performance.
Stiffer springs and better damping to allow you to better use the performance that you do have.

If you are a cheapskate like me, you will end up just pumping the tyres up a bit
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Old 11-19-2006, 02:03 PM
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^^^well put, i am going the "cheap" routes so to say, i have custom fabed up a new intake, and have done full exhaust, and hopefully wednesday i will be doing a tune with a SAFC. i can honestly say with my mods i have lost near all lowend, however once the car reaches around 2900rpm it gets real happy real fast. i have every intent to do equal length headers, cams and some pulleys soon, to date i have about $350 into the build, and i am more than happy, come wednesday it will be slightly over $500. my goal is me still doing most if not all most all of the work on the car, i hope to yield just over 200 AWHP with the standard automatic transmission and to do it all under $1,000. like i said, i am tuning via a Apexi SAFC and wideband O2 sensors, i will let you know what the power turns out to be once its done, just out of curiousity, what kind of power are you looking to achieve?
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