Upgraded lightweight internals - ECU changes and benefits?

[veey]

I'm thinking of making some changes to the internals of my engine,namely:

1. Titanium connecting rods
2. Lightweight valve train
3. Heavy duty rod bearings

Would any changes to my ECU be necessary if all else is left alone?

Would I experience any increase in wheel horse power as a result of the reduction in reciprocating mass? I'm assuming the engine would rev higher much quicker.

Opinions welcome

 

[GregLocock]

1. Titanium connecting rods

Very minor effect on hp

2. Lightweight valve train

detectable effect on hp

3. Heavy duty rod bearings

negative tiny effect on hp.

Assuming you are measuring real hp, as opposed to making a wild guess at it via an inertia rig.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[patprimmer]

The mods you propose are not typically very cost effective.

The main advantages of light weight moving internal engine parts are:-

Less stress on other parts as engine revs increase, increasing the potential to rev higher from other mods.

Less power consumed to accelerate the motor parts, so increased acceleration is obtained without an increase in actual measured steady state power.

Simply reducing the weight of the flywheel might be a lot cheaper and reducing crank weight might be somewhat cheaper.

So long as cam, compression, manifolds, exhaust, throttle bodies and ports are not changed, the ECU will not need a change unless you wish to raise the rev limiter cut in speed.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[GregLocock]

Oh, so needless to say, your current calibration is still valid.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[IceStationZebra]

$2000 for titanium connecting rods
$1200 for lightweight valve train
2 extra Hp --- priceless!

Seriously, Pat and Greg are right that your choices have a very low bang for the buck. Usually the cheapest and biggest return on effort is to reduce the weight of your vehicle, especially wheel weight. Lighter wheels benefit your handling and reduce your rotational inertia for a slightly quicker rev. The next steps are usually improving air filter/intake restriction, exhaust restriction, and valve timing.

The best thing to do is find some enthusiast web sites for your particular vehicle. They will have tried most of the usual tricks and can tell you which ones are worth it.

ISZ

 

[Tmoose]

Making horse power is easy, but it all has to pass through here.

http://classichemi.com/HPIM0145A.JPG

All I hve to do is Get a lot of mixture in every cyinder, mixed with the right amount of fuel in every cylinder, squeeze it tight, and ignite it at the right time.

 

[dicer]

Ti con rods? If you go to that expense, what about the crankshaft? Is it a stock crank or a $3000. item? And then the pistons are they stock castings? Oh and then the block or crankcase, will it handle this extra power? The place to start is the head and cam department. So what brand engine is this? Size etc. And planned HP and rpm range? What is the use?

 

[veey]

I'm just wondering what I could do to reliably raise RPMs on my current motor, which is a Toyota 2ZZ-GE. It currently redlines at 8.5K but I would like to raise it to 9.5K or 10K. I'm not sure whether this project has been undertaken before, so I'm doing my research.

 

[patprimmer]

Changing the chip might raise the rev limiter cut in point, but you will only get increased rpm and power if the airflow and the fuel flow are sufficient to support the extra rpm.

As the engine was probably not designed to run reliably at this rpm, bitter experience will probably indicate the weak points and therefore what requires heavier duty parts for reliability.

Maybe someone here has run one of these that hard, but you might do better at a car club type forum specialising in your engine type.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[veey]

No doubt airflow, fuel supply and cooling have to keep up with the increased load. The motor can currently do 8.5-9K in short transients but whether the block, crank and pistons can take the load at higher rpms is something that needs to be checked out.

 

[strokersix]

How about knock sensor calibration? Would internal engine noises with the new components be enough different versus the stock components to affect calibration?

 

[mishar]

Your engine is limited at 8500 rpm but it develops maximum power quite lower than that. Probably 7800 rpm or so. If you reprogram ECU to allow higher rpm you will not get any power increase. Lightweight internals will not bring anything significant either. In order to get some power increase on higher rpm you need camshaft with longer and higher profiles and stiffer valve springs in order to secure that valves will follow cam profiles on high rpm. This part can be done with lighter valve train too, but it is more expensive and with limited results. Valve job and head porting can help a bit too, but modern engines are quite good that way from the factory. You have to be prepared to loose some low end power and burn more fuel. Also you can have problem with idling and vacuum for brakes.

Be aware that most of “results” you can find on forums are somebody’s marketing combined with wishful thinking.