Can anyone give me any info on modding port and crank timing?

Jon, i got your PM and sent you back one as well.

cool thanks.

anyone else?

come on, some one has got to ne able to help me right?

What info are you looking for?

how far do/can I take the ports is there a certain number of degrees of duration that I have to have, where the line that once you reach it you start to lose power instead of getting power.

what to do on the crank timing, I heard 240 degrees of duration on the crank was max, is that true?

I don't have money for trial and error, so I when I do this and I mess up I'll be short an engine, and/or a car with no engine.


I'm trying to learn as much as I can about engine modding, I know how to mod the outside of the ports but know I want to get more power out of my engine.

There is no way to cover that in just a few sentences. For exhaust ports I've seen a CMB .90 run with 205 deg exhaust. It flat out hauled butt at high revs but going that high will kill the low end completely. This would be completely useless for a car engine. I think staying below 175 is good for our case.
If you need more power at high rpm you need to increase exhaust duration and run shorter pipes. You also need to adjust the compression ratio. When you increase timing you reduce the trapped compression ratio and you will need to mill down the head to compensate.


I don't have an answer.


Buy the MOTA engine simulation program. You can enter any timings and dimensions of pipe you like and it will give you a hp vs. rpm chart.
I have it and it's well worth the money.
It's really interesting to see what a change will do and you will learn more by playing with it than anything else and it doesn't cost you any broken and ruined engines. Once you get an idea what you like to try just go ahead and mod accordingly and see how it works in real life.


That's the best I can say.

Thanks SMan,

and when you say mill down the head, do you mean make the head sorter or ad shims, or drop the head down, like removing shims?

is this the MOTA your talking about http://www.iwt.com.au/MOTA.HTM and what about something like this http://www.performancetrends.com/Eng...r_Pro_v3.3.htm

Basically drop the head down. Take out (for example) 0.1mm on the squish band and an equal amount on the flange resting agionst the liner. This will reduce the volume of the head button. Remember to keep the piston to head button distance the sme as it was.

Yes, MOTA is the package I have. It's great.
The other one I don't know anything about.

I'm still alittle confused (bare with me, I just want to fully understand this) so just remove a shim, right?

I'm trying to find some cheap enignes that I can do some testing on.

Remove a shim and remove an equal amount on the squish band.

OK, Thanks.

Remeber, always keep one shim to keep a good seal.

Ok, I'll work on a wore out engine I have and try to get the hang of it, then try to find so cheap engines that run to see what works and what dosen't, but hopfuly theres more dose then dosen'ts]

Buy the software

I can't really afford $200+ software, is there anywhere in the US I could get it from?

No.
It's still cheaper than cutting up engines randomly.

yeah, but the only thing is, I only have about $140 to spend, because I still haven't been Chirstmas shopping yet

Hehe, just skip Chrismas and save another $60. Problem solved.
You got to get the priorities straight man. LOL

ive looked for a free copy with no luck.

Forget it. It uses a hardware lock.
It's cheap compared to everything else related to RC.

hardware lock heheheheheheh. ive come across one type of software protection that is difficult to get past. that is starforce protection. used on games like toca 3. even then all you have to do is unplug your cd drive. basically what im saying is that everything is crackable.

edit: its not available because its not mainstream enough for someone to have put it up for download.