I was just wondering what the cost of a 3rotor vs a 4rotor would be and if a 4rotor was realatively cost worthy, and comment well come i plan on building an engine over the next couple of years and was wonder about people comments feel free to comment.
thanks

 

3 rotor $15k
4 rotor ~$30k

i doubt you can afford it son.

 

well i make $19hr and work long hours, ! want to build an engine over the next 3-4years, but you would suggest 3rotor?

 

Sure.

 

i'm also having a hard time finding engine parts that are relatively cheap, if anyone has any links to some site that would be great i'm having a hard time finding info on this site and on the web

 

there is nothing cheap about a 3 rotor, this post is making no sense. the intermediate housing has been discontinued from mazda and will run you close to $1k for a brand new one if you can find one now.

if you keep saying words like "cheap" i am done with this since it obviously makes it sound like you ignored my estimate. $15k for an engine/fuel/EMS is quite a bit of money...

 

ok my question should be this, how hard is it to make a 3rotor vs a 4rotor if money wasen't the question?

 

ok no more cheap talk, i'm just looking for some serious imput on this subject, so 3rotor is more feasable, then do u have a link to a site that might have some parts i'm looking for, i'm sort of a newbie

 

Well......
3 rotor is a mass produced engine from Mazda

4 rotor == Complete one off production with 4 rotor ecccentric shafts being the only part for sale that I know of. Everything else custom fab.

The only type of person able o pull off a 4 rotors is someone who has **** loads of money to spend on other people doing the work for them or a crazy professional rotary builder.

3 rotor is the way to go. That project alone will make insane HP and is still unique.

 

it isn't difficult at all, you can find where to buy most of the parts to build the motor in the 3 rotor section on this forum.

forget a 4 rotor, i believe only a handful of people in the world have built 4 rotors and the majority of them was by mazda for the 787B. $30k was actually a low estimate.

for engine management there is the EMS section the forum and for fuel system there is the general rotary tech or you can get an idea from others in the 3 rotor section.

3 rotors were mass produced but with most any engine, to do it right it should be rebuilt and parts are not exactly easy to come by and will only be more difficult to locate as time goes on. when you look around you won't see all that many people running 3 rotors and if you ask them how much they put into it, expect them to start at the figures i put up and go up from there.

 

yes i understand that it will cost me alot of money but i really need another hobbie, i do apprisiate the help very much and your talking 15k US or CAN?

 

Us

 

You're in Canada? I can build you a 4 rotor. Cost is $50K for the engine. $25K due before the work starts. If you want me to install it and wire it, add $15K.

As for the 3 rotor, you will be hard pressed to get a complete install for less then $15K. Check out the 20B forum on this site for more info on what it takes.

 

thanks you guys have been a huge help, might go supercharged 3rotor hows that sound? many thanks guys!

 

dude 3 rotor na is def cooler

Goodluck with this project

I heard that the guys that made diy 13bre are making a do it yourself for the 20b

See if you can look into it.

 

i'll look into that, thanks

 

people understimate this crap, just don't waste other people's time on projects like this.

it isn't easy to save up and fund large projects like this unless you have no life and make a fair amount of money, for the most part people think it sounds fun but easily by the time they are 20% through with collecting things they soon realize it isn't as fun as they thought it would to have dumped $5k into it and realize they still need twice that to get any kind of satisfaction out of it still and are burned out at that point. i just hope anyone who thinks about this realizes how seriously long of a project it is and how expensive it will be to even see a near finished product.

 

i complitely understand what your saying thats why i planned for at least 5years to get somewhere with this, i know it won't be easy either, but the questions i have i was looking for some respected optionions and i have found some info i'm going to look into from you guys.
so thanks

 

Junior, Look before you leap, Learn to walk before you run. OK, Grasshopper?

On a scale of 1-5, How much mechanical experience do you have? Any of it rotary experience?

Building a 20B would be a major undertaking even if you're familiar w/ piston engines. By all means look into one of Aaron Cake's post of his rebuild of a 13b and then see if you still want to do this. Then get the Atkins video before you even think of going 20B building. Not trying to discourage you but informing you that this will take a lot of patience and dedication to get what you want. Now the question is, How bad do you want it?

And yes, A supercharger would be awesome w/ the low end torque of the 20b already higher. But finding a supercharger w/ the kind of displacement and the ability to hold itself together at the kind of rpms the 3 rotor spins at the top end is going to be hellaciously cost prohibitive. Would be insanely awesome on a track though. HMMMmmmm, Sounds like a future episode on PINKS.....

 

i do have some mechanical work with piston engine and a little bit of rotary but i read alot and the answer to your question is I want it really bad i'm in love with rx7 since i bought my first one, well if a supercharger is going to cost to much then maybe twinturbo would be more cost effective

 

Well, here's my opinion...

If you have been planning for 5 years, all these are questions you should have answered for yourself 4.5 years ago. People are being a bit smart-assed because this is all really basic stuff that anyone serious about taking on a project like this would/should have researched on their own.

We get topics all the time that read like "I'm 16 and make $7 million per hour...How can I put a 20B into my bone stock 4 lug NA with rotted out fenders and how much will it cost?"

And after a few replies it tuns into:

"You guys suck! I'm totally serious and have been planning this for like forever. Now what's better, twin turbo or single turbo? Maybe I should just make a 4 rotor?"

Then:

"Wow. That's expensive. Maybe it's cheaper if I find an old diesel turbo from the wreckers and use that?"

This person who makes $7 million per hour suddenly realises that none of this is particularily cheap and starts thinking in terms of reality.

And then a few more comments by people who know, and then the topic dies and the poster is never heard from again...

So, the moral is this:

1. Do some of your own research before you start asking questions. There is a 20B section on this site with a very informative FAQ that would have answered everything in this thread. Clearly this research was not done based on the questions answered.

2. You can't just buy a 4 rotor. There are very few of them in the world. I can make you one for the price quoted earlier. But when we start talking numbers, suddenly the discussion changes direction.

 

I've seen a Drag Racing team in Sydney who built a 4rotor in a BMW. It has 1450hp and runs 6 second passes. Having said that, they did make a custom turbo that produces around 34psi and a whole lot of other custom engine components. I would be lying if I said I knew how much it cost because I have no idea

 

If your new to rotary engines I would recomend a 13b (two-rotor) with a single turbo on it. Then if you can keep her running for a while play around with it before you blow her (and you will dont feel bad) rebuild her a few times while building your tool collection. Then if you think your still love em go for your 3 rotor. If you do indeed make 19 a hour the majority of your paycheck will be going to your baby anyways maintenance. No joke. I dont know how mutch experience you have with other engines but you should know that these engines take less abuse and are fickle.


Ohh and





Sorry I had to do it....

 

He meant he was planning on doing it in the next 5 years.

 

yes that is what i meant, i'm planning on the project to take five years