Engine Modifications
 

Hi Guys,

Does anybody know of someone who can do modifications to standard engines like os 12 tr (3-port) to make them faster?

i have tried a asking a few shops here in JB, but i don't think they even understand the basic concept of engine modifications such as alteration of inlet and exhaust port timing and compression ratio.

They may be good at selling but when it come to technical stuff, they seem to be lost...... i heard there are quite a few of good engine modifier in Singapore.

Does anyone know who are they?

there are a couple of tuners in KL..but that's about it.
engine modification is very 'touch n go'.sometimes u get it right ,sometimes not.
but u can definitely port/polish ur engine for a bit more power.

I don't think in Malaysia (or SG for that matter) do you have people who make part of their living modifying engines... I may be wrong.

Most do it for their own or as a favour to friends to test out their mods. This is because most of the time, modifying engines can be a little risky. If not done correctly, you make worst performance out of the stock engine. It's a challenge though. If you have the proper tools and lots of guts armed with some knowledge, you could try them yourself.

If you can read Japanese, you can probably take a look at the Japanese magazines (RC World) and see what they do to the OS, RB and Nova engines:nod:

Yup, correct. That is the reason why I don't think any of them are selling their modified engines openly.

It's more to port and polishing the engine for performance. People used to have that mindset when the old JP engines came into the market. JP engines are just that... Port and polish. No actual change of exhaust height and cranks intake timings.

The new ones have some more alterations to the crank and a little to the sleeve. But mostly, the crankshaft is the one that contributes the most power after the modification of the carb.

I think Stevehan has the correct mindset. Most of the engine power comes from altering the engine timings. Not the fancy art work on the piston sleeve you see on JP engines. Even the new JP engines spot very minimal carvings on the sleeve.

To those who want to get modified engines or powerful engines that do not give them much headache, I suggest they go with factory modified engines like the Rody or the JP engines.

Modified engines like M-speed are just nice to look at put pricey. I heard that a Rody tuned engine will easily outdo an M-speed engine. So don't bother with it. NEXT engines are nice too. These are real hand modified engines.

Looking globally, you'll find that the Ritchey RTU, SMELTZ and the Murnan Modified engines are one fastest modified engines.

The next crankshafts doesnt look like it is ported in a sandardise manner, looks like it has quite a bit of difference between each crankshaft. I also thought motorman mentioned that there are some area that should not be polished.

I think those pics of the crankshafts are for .21 engines. I'm told that they do not make / modify .12 engines but upon request and if you want it done according to your specs, then they can do it for you.

Anyway, you are right that only certain parts will benefit from being polished. From the pictures, you cannot always see what is done to the crankshaft. The crankshaft intake window may already have been widened to increase the intake duration and increase the air / fuel volume. This translates to more power.

it's really a big hassle to modify an engine already in hand.
i would also recommend just getting a Rody or something.then u can also be assured of some standard by which u can measure how much speed per RM450 extra that u paid for it!
anyway there are always guys that want something really special that they can boast about!

.12 Sirio
 

Hi guy! The crankshaft I saw in the picture is the same with sirio .12 design. Is that true?

Just suggesting
 

Hello, just to share my experience, once i tried to machine my caburator intake hole slightly larger to induce more air intake in one of my old carburator and fix it on my engine. The effect is quite obvious and the speed did increase noticebly, but the problem was after some runtime, my conrod broke. Guess the conrod was not meant to take up such high combustion, as i notice that those mod engines all come with reinforce conrod. Just my experience to share, thanks for reading.

First of all do understand all outlaw are illegal. If the races do allow it, do use it. It is really fun to have a powerful engine.

I can understand why drivers need mod engine, it's just faster and it is an honour to have something that's different in the market.

Best engine I ever see on the market. M-Speed. No doubt. Though pricey, worth every penny. Low end, high end and consistency. Why so expensive, I guess the factory only give you the best. So anything is inferior is simply rejected. So it's just quality and performance.

Other engine like Rody, JP, Carlsson, Fantini, blah blah are all mod but still lacking behind. Especiallly the low end.

So in the end, is working on the engine by all this engine guru, worth it?? You take your pick. Not even worth it. Cause if they are good, they should be making money like M-Speed. Once they screw it up for you. You can kiss your nova, rb, os etc good bye.

I actually have not seen a race in Malaysia (except maybe for the Asean Gas Open) that prohibits a racer to put a illegal .12 engine in his car:lol: :nod: All on road races here go like that.

Even the Asean Gas Open has opened to accepting 5 port engines now. Back then, only 3 port turbo engines were allowed.

That's where I think people have the misconception... Having the best looking engine internals does not necessary make the most power.;)

I believe the M-speed engine is just a rip off. It is powerful no doubt but nothing a Rody or a Fantini cannot do. The M-speed engine may have better lower end no doubt but other engines have better high ends. No engine out there is good in each and every compartment. Good in low end but a little lacking on the high. Good on the high end but lacking on the low. To compensate for this, gearing of the car is most important. A car equipped with a high revving engine should use a low end fat and longer big volume pipe. This will unload the engine better at the low end. A high revving engine should be equipped with a smaller pinion / bigger spur combination to compensate for the low end pull.

Re: Just suggesting
 

I don't think your mod of the carb has anything got to do with the conrod breaking. I may have accelerated the aging of the engine but I think it's more like the engine has been over revved or could have gone too lean on the carb. Of course, more air goes into the carb, the higher the performance you get. To maintain the same air fuel ratio mixture, more fuel needs to be used. If you retard and do not use more fuel, the engine will go lean.

The normal Rody tuned and factory mod engines engines like JP do not use special heat treated parts. They use the same parts as the normal out of the box Novarossi S5 (for JP) and RB X12 (for Rody tuned) engines. That is why in a way these engines wear out faster.

If you go with NEXT or certain custom hand modded engines I know in US, they go as far as to heat treat certain parts of the engine internals and doing extra stuff like shot-penning the inside of the piston, ultra-coat the bottom part of the piston for anti-scuffing at high engine RPMs and etc.

Basically, the main reason for modification of engine is to increase it responsiveness, and ultimately its hp.

With all these modifications done to the engines, you cannot expect the engine to perform like an all-rounder, either you will have outright power at the start or agressive mid or high end punch.

Take the F1 racing engines for example, the powerband is designed to a certain rpm say, 7000~16000. that is why you find so many gears in a F1 car to compensate for this lag below 7000 rpm.

I must say, I am quite impressed with InitialD with your reply, do you do any engine modification too? You seem to know your engine very well! Not much people in this hobby even have the slightest idea on how their engine works.
:)

Thanks for the compliment:) I am what people say a wannabee engine modifier:lol: I try to do very little engine modification to my own engines whenever I have an inspiration when looking at other modified engines internals.

There are many things to look into when modifying an engine. But most of the times, people learn the tricks to modifying engines by looking at the modified engine internals.

Looking at it alone is always never enough. You must understand why it is done the way it is done before you do the mod yourself. Copying alone cannot always guarantee a perfectly working engine.

Yes, that is why a Centax style clutch is very effective in a way. For other style clutches like the 2 or 3 shoe finger type clutches on the NTC3, you need to use harder springs and probably lighten the shoes to help the clutch engage at a higher RPM range.

For small nitro engines, you also want the 2nd gear to engage when the engine powerband is at it's highest torque. For Nova engines, the RPM range is usually at 30,000 rpm.