P5 Tuning general question

[gunners]

I don't know much about tuning (except general stuff and that it makes your car go much faster!!!!).
However, my question is.. how does tuning up your car affect its reliability? There must be a give and take situation somewhere.... it just can't be all good!!!
Does a tuned-up engine last as long as a non-tuned one? What are the counter effects???
Any help appreciated before I decide whether it's worth investing all these bucks in mods and what not.

 

[1sty]

Basic stuff like large exhuast and a CIA that isn't in danger of sucking water is nto goig to in any way hurt the car. Also a properly installed head won't be bad either. Underdrive pulleys, cams , higher compression pistons and things of this nature will start to degrade reliablity.

 

[Blown]

I'd have to disagree with you about underdrive pulleys. How can they degrade reliability when in fact they reduce the amount of strain on the engine's accessories? Thus, increasing the longevity of them. Now, when you're replacing the crank-shaft pulley, that is a different story altogether. If our cars have a harmonic balancer, then you'd be shorting the life of your engine. However, do our cars have one?

Now back to the original question. Yes and no. If it's done right within the tolerances of your engine it's all good. Your best bet to being safe but increasing performance is installing the I/H/E (intake, header, exhaust) combo. In essence, it's just correcting the inefficiencies in the stock equipment.

 

[1sty]

BEst I can explain, it is weel documented not to do underdrives, not lighter but underdrive, on miatas and you are garenteed to have issues. I have also read many articals saying they have been known to cuase probelms. Of coarse this all could have to cars with harmonic dapeners like you mentioned.

 

[gunners]

Now back to the original question. Yes and no. If it's done right within the tolerances of your engine it's all good. Your best bet to being safe but increasing performance is installing the I/H/E (intake, header, exhaust) combo. In essence, it's just correcting the inefficiencies in the stock equipment.

How significant would be the power increase if I modify the I/H/E combo?
Can all this be done without having to invest in one of those "loud" mufflers? Does "loud" correspond to "power"?
Aren't there "more civilised" mufflers on the market?

I have a friend who has a VTi Civic with a Sports Muffler and Boy it's loud!! Can't hear anything apart from the muffler and the whole car frame vibrates inside!!

 

[1sty]

No, loud doesn't correspond to power although any larger diameter muffler will be louder then stock. The most you'll see from all that is around 15-17 WHP. Which would be about a 20% increase.

 

[Blown]

I would have to agree with you about the power increases but typically you'll lose some of your low-end torque. Now, all of that can be seen without using a loud muffler. Typically, a quality cat-back is not loud. If they are, you can always install an silencer in the canister type mufflers or even add a resonator to the system.

1st MP3 - Most Inline 4 motors do not have Harmonic dampners. They are typically seen in V6 & V8 engines. Most underdrive pulley sets do not remove the dampner unless you replace the crank pulley. I personally think pulleys are useless and don't net any significant gains in power. I've had them before and I wasn't impressed.

 

[1sty]

You should search on them in Miata boards i know they cuase several issues.

 

[Blown]

1st MP3 - I don't deny that underdrive pulleys potentially can cause problems and when I get the time I'll research into the issue more. I used to drive a JRSC miata and I don't remember there being a harmonic dampner on it because the supercharger crank pulley bolted right into the regular crank pulley. What kind of issues did underdrive pulleys cause on miatas?

 

[1sty]

Water pump failure is memory serves.

 

[70]

1st MP3 - I don't deny that underdrive pulleys potentially can cause problems and when I get the time I'll research into the issue more. I used to drive a JRSC miata and I don't remember there being a harmonic dampner on it because the supercharger crank pulley bolted right into the regular crank pulley. What kind of issues did underdrive pulleys cause on miatas?

\

Yes, Miatas do have harmonic balancers as well as the Protege. There was an extensive discussion on this board covering the very issue of under drive crank pulley's on this very board.

Turbo Miata, premature failure with the underdrive crank pulley. N/A did ok with it I think.

Basically, underdrive crank pulley is bad. Underdrive accersories pulleys, potentially worthless and might cause more strain on the actual part. Which won't be worth much in the long run for the minimal gains seen.