Was thinking of building a street ported TII block with S5 NA rotors and stat gears.
Anyone ever done this?
I would obviously be using an EMS to do this to squeez out as much power as possilbe.
Any comments?

 

SEARCH! I had to say this at least once.

 

i just finished doing about 2 hours of searching and didnt find anything but people turboing NA motors... would you mind linking me to what you've found???

 

Here's some

1) https://www.rx7club.com/showthread.p...s+turbo+engine

2)https://www.rx7club.com/showthread.p...s+turbo+engine

3)https://www.rx7club.com/showthread.p...s+turbo+engine

4)SEARCH SOME MORE NOOB

This is from <10min of searching.

 

Of course it's possible.
It's convenient that the counterweights are identical for same groups of FC's (Zenki versus Kouki) no matter if they are non-turbo or turbo.

Now, it becomes a question of tuning and fuel octane that will dictate whether the engine blows up or not.


-Ted

 

Those thread arent what i'm looking for. So quit with this NOOB bullshit.

I'm NOT turboing the motor. I'd be leaving it NA. So let me specify.... Who is running a T2 BLOCK with NA ROTORS and NO TURBO????

 

Has anyone come up with a verdic on those numbers yet?

 

As far as what? Really it depends on the levels, who tunes it, timing, AF/R, and intake temps/intercooler temps.

 

https://www.rx7club.com/time-slips-dyno-128/tii-na-streetport-dynoed-186whp-482741/

This was done with 9.0:1 TII rotors and a porting style geared toward a turbo application.

With the right exhaust and tuning and the 9.7:1 NA rotors expect to break 200 RWHP.

 

why whould you want to run it NA? if your going to bother with a standalone you might as well just keep the turbo and just tune it and make lots of power. I would also figure that since the NA block is different then a TII block then there must be a reason Mazda did it.

 

This is generally a bad idea. Mazda went through a lot of trouble designing the intakes for the T2 and NA engines for the specific applications. Puting NA rotors in a T2 block will get you less power then a full NA block.

 

I fail to see how those threads aren't relevant. True they may be turbo but, the ideas and methods to putting the NA rotors in the Turbo block are still there. There's still plenty of info for you to use there.

And the NOOB thing was just some ribbing like the first post. :p

 

so in other words...he wants to know who's running a 4-port turbo 13b with n/a rotors and running it n/a?? can it be done?...yes it can. can you expect power gains vs. a 6port?? probably not but i leave that to the ones that can prove it.

but like what dragon said, the links tell you it is possible whether turbo'ed or not.
ted hit it with the rotor balancing. it's all there

 

^^^^^^^^^^^

no
he is asking if anyone ran higher compression rotors on a t2 engine.

 

when i said 4port turbo 13b i meant the block...sorry if i wasnt specific with my words...

 

shut up. kahren is runing a t2 block with i dont know what rotors, but hes making close to 200 whp. he seems to be proving that mazda didnt do everything correctly.

 

OK, let's clean this up a little...

So your goal is to build a 4 port NA engine? Fair enough, it's been done plenty of times.

You can build a TII block with NA rotors by simply swapping the rotors. Keep in mind that S4 rotors vs. S5 rotors have different weights, so you will need to match the counterweight and flywheel if you move cross-series. Check out the chart:

http://www.mazdatrix.com/faq/rotorwgt.htm

The argument of 4 vs. 6 ports is an old one and I'm not going to get into it. Suffice it to say that if you are looking at making monster ports, the 6 port irons have much more room for porting. But if you are actually going to be tuning these ports with regards to shape and manifold, then the 4 port irons will make this a lot easier. You can apply the same porting techniques (for example bridge) to 6 port irons as you can to 4 port irons. The TII manifold lacks the dynamic effect intake that the 6 port engines have which may or may not be a problem depending on what you are doing.

 

If you are talking about a 4port turbo motor and swapping in the 9.7.1 rotors from a S5 NA? Then yes you can do this.

Ericksseven did just this "sorry if I misspelled your name" many others have as well. All the rotors are the same they just weigh different amounts and have different compressions so they are all interchangeable. Providing the correct counter weights are used. FYI as ReTed said all S4 counter weights are the same and all S5 counters are the same. The S5 stats are hardened so if you want to rev up more like the S5 then use the S5 stats. As well there is a letter stamped on the gear side of the rotor. These must be paired within one letter of each other. So a D and C can be paired but a B and D can not.

 

well if your going to put s5 rotors for the high compression, why dont you put rx8 rotors, arent they even higher in compression????
i want to do basicly what you want to to do, but dont know which block (4 port or 6port) would be better for a bridge port... i thought the s5 4 port were better cuz you get more horse power, thats what i thought though cuz im no expert

 

Using the Rx8 rotors may or may not give you more gains. There hasn't been enough work to really know what will happen. Don't forget, while the Rx8 rotors are lighter and higher compression, they've also been designed to work with side exhaust ports and have shaved sides and other changes. It's something to experiment with, but is still expensive.

 

yea i guess thats true but the thing was that since rx-8 rotors are cheaper, than s5 and s4 now that maybe it might be a good experiment, but when you plan things, you never notice the little things that drains you pockets quick....
what about the 4 port and 6 port, even though the horse power change was between s4 and s5 is thier any dramatic change in both blocks, cuz it would be alot cheaper with a 6 port( since in my case they are more availible.

 

The HP gain from S4 to S5 was on both the turbo (4 port) and NA (6 port) engines.

The NA gain was mainly due to a higher compression ratio and better intake design.

The turbo gain was mainly due to a little more boost and a more efficient turbocharger.

For bridgeporting, tradition says that 4 port blocks are "best", but the 6 port will give you more port area and room to work. The 4 port manifold is better for radical porting since it is not tuned like the NA intake and thus you can't screw it up as easily.

 

Thanks Aaron Cake, by the way did you close that racist guys page, that was pretty funny on what he said