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-   -   medium street port HP? (https://www.rx7club.com/naturally-aspirated-performance-forum-220/medium-street-port-hp-1129254/)

flyingclay 08-20-18 08:11 PM

medium street port HP?
 
I have a medium street port 13b. What hp can I expect to get out of this whit a NA fuel injection? Is there something I can do to increase the HP without adding a turbo and different porting like, intake design, exhaust mods, and anything else that would increase HP.

Thanks for the input

13.bREW 08-22-18 11:49 AM

At most probably 210-220 but that is a load of work done. ITBs, ECU, Coils, Injectors and all the things that support those upgrades. If you want to do it proper its going to cost a shitload of money and unless you really want an NA rotary its probably best to just go turbski. I did go full NA build though and I love it so far. What I suggest for someone in your situation and what I would have don't in hindsight is kept my car stock. from there get an ECU. Then Light flywheel and header back Exhaust. Then injectors and Coils. Then ITBs. Then Pull engine and port/ rebuild or whatever, because by then you basically have everything running before you go full HAM with the hard parts. https://cimg4.ibsrv.net/gimg/www.rx7...74242d3282.jpg

dguy 08-22-18 12:36 PM

Not to be a contrarian but if this is a second gen and NA application I don't really see the benefit in putting coils high up on the list. I've been involved with plenty of builds/tunes that kept stock coils or twin trailing coil packs with additional igniters for a direct fire setup. The only negative is that they're large. Your $400 + labor is better spent on other things such as getting building the basis of your exhaust and then maybe ITBs.

13.bREW 08-22-18 12:58 PM

My car is the first big build I have done and I didn't have any outside help other than my own research so I wasn't sure what to do in the beginning. Coils were high on my list only because I wasn't sure what the setup was like for the standalone options. Some wouldn't plug n play the Rx7 Coil setup and some would, but everything can do direct fire. I went with the Haltech Elite 750 which turns out it can. Also personally I wanted to clean up the look of the wiring and whatnot in the engine bay and the AEM coils were much easier, for me, to accomplish that.

diabolical1 11-18-18 01:52 AM


Originally Posted by 13bREW (Post 12295975)
What I suggest for someone in your situation and what I would have don't in hindsight is kept my car stock. from there get an ECU. Then Light flywheel and header back Exhaust. Then injectors and Coils. Then ITBs. Then Pull engine and port/ rebuild or whatever, because by then you basically have everything running before you go full HAM with the hard parts.

There is much wisdom in this advice.

KNONFS 11-19-18 08:14 AM


Originally Posted by diabolical1 (Post 12314361)
There is much wisdom in this advice.


Agree, its a very logical method of following an upgrade path.

fidelity101 11-19-18 01:45 PM


Originally Posted by flyingclay (Post 12295634)
I have a medium street port 13b. What hp can I expect to get out of this whit a NA fuel injection? Is there something I can do to increase the HP without adding a turbo and different porting like, intake design, exhaust mods, and anything else that would increase HP.

Thanks for the input

160-190whp realistically

Dak 11-19-18 02:10 PM


Originally Posted by fidelity101 (Post 12314612)
160-190whp realistically

So if 200whp is obtainable/has been done on the stock S5 manifolds( though 180whp seems to be the plateau most don't get past) what is the benefit of going to ITB's? Is it just power delivery or where it makes it's power?

Kenku 11-19-18 03:36 PM

Far more is possible than 200whp with a streetport without the stock S5 manifolds.

fidelity101 11-20-18 01:09 PM


Originally Posted by Kenku (Post 12314627)
Far more is possible than 200whp with a streetport without the stock S5 manifolds.

^^ This.

I can tell mine is being choked above 7500rpm, its getting plenty of fuel but not enough air at a short enough runner. I saw just under 200whp on the mustang with stock S5 manifold (VDI wired open) but because of classing I need to keep the mainfold (for now)

peejay 11-25-18 08:55 AM


Originally Posted by Dak (Post 12314618)
So if 200whp is obtainable/has been done on the stock S5 manifolds

It hasn't, except for a few situations of a really good engine and a really good exhaust setup and a really good tune. It doesn't happen by accident or even by bolting up the right parts.


( though 180whp seems to be the plateau most don't get past) what is the benefit of going to ITB's? Is it just power delivery or where it makes it's power?
Drivability, not power.

ITBs have a lot more drivability than any plenum manifold.

If all you care about is power, then fark it, throw a V8 in it or a turbo or nitrous (all same heresies IMO) and go drag racing or doing burnouts around a corner or whatever it is that people who only care about max power will do. Probably vape and play Xbox and put ketchup on hotdogs and all the other horrible things in the world. If you want a responsive engine that makes driving the chassis with the throttle easy, then ITBs are the only answer.

It is sort of the induction equivalent of the difference between a 7.5" clutch setup versus a stock 30 pound flywheel.

j9fd3s 11-25-18 09:47 AM


Originally Posted by peejay (Post 12315594)
It hasn't, except for a few situations of a really good engine and a really good exhaust setup and a really good tune. It doesn't happen by accident or even by bolting up the right parts.



Drivability, not power.

ITBs have a lot more drivability than any plenum manifold.

If all you care about is power, then fark it, throw a V8 in it or a turbo or nitrous (all same heresies IMO) and go drag racing or doing burnouts around a corner or whatever it is that people who only care about max power will do. Probably vape and play Xbox and put ketchup on hotdogs and all the other horrible things in the world. If you want a responsive engine that makes driving the chassis with the throttle easy, then ITBs are the only answer.

It is sort of the induction equivalent of the difference between a 7.5" clutch setup versus a stock 30 pound flywheel.

asking for a friend, but what are you supposed to put on a hot dog?

i think the highest we've seen on stock hotdogs, err manifolds is about 180rwhp. Chris Ludwig did an FC, engine was ported lightly, and then someone 84 did an S4 engine, everything got massaged.

the guy from Revolution Rotary, in Japan, spent 6 months with the Rx8 going between the flowbench and the dyno, and came back with 230rwhp, they sell it as a package, 16k

peejay 11-25-18 12:23 PM


Originally Posted by j9fd3s (Post 12315610)
asking for a friend, but what are you supposed to put on a hot dog?


Sauerkraut, or instead maybe mustard and some diced onion if you are not feeling very awesome that day. Or leave it alone and have meat on a bun.

You can buy these things (hot dogs with sauerkraut) at street vendors in Cleveland and it is, in fact, the best thing ever. It's why people go to Browns games.

BLUE TII 11-25-18 12:32 PM

And eat with your knife in your Right hand and your fork in your Left hand you god damn weirdos!:crackup:

j9fd3s 11-25-18 12:55 PM


Originally Posted by peejay (Post 12315642)
Sauerkraut, or instead maybe mustard and some diced onion if you are not feeling very awesome that day. Or leave it alone and have meat on a bun.

You can buy these things (hot dogs with sauerkraut) at street vendors in Cleveland and it is, in fact, the best thing ever. It's why people go to Browns games.

that does sound good! the sauerkraut was actually quite different in Germany, it was less tart and more sweet. and the mustard had some horseradish in it

j9fd3s 11-25-18 12:58 PM


Originally Posted by BLUE TII (Post 12315644)
And eat with your knife in your Right hand and your fork in your Left hand you god damn weirdos!:crackup:

but i'm left handed? and who eats a hotdog with a knife and fork?

peejay 11-25-18 01:06 PM


Originally Posted by BLUE TII (Post 12315644)
And eat with your knife in your Right hand and your fork in your Left hand you god damn weirdos!:crackup:


Wait is that not normal? :dunno:


https://cimg9.ibsrv.net/gimg/www.rx7...a210d7b934.jpg


Dak 11-25-18 03:01 PM

Couple more questions on ITB's since we've got the hotdog problem solved, though I do put ketchup and mustard on mine maybe the mustard balances out. I will have to try the sauerkraut as it's good with kielbasa cut up in it.

Does one not notice loss of the supercharging effect from the other rotor when you ditch the dynamic chamber of the S5, or does the better flow shorter runners of the ITB setup make up for it? Is it's effect really not much and is more Mazda marketing. I thought there was a sae paper showing it really did increase power somewhere? Also Peejay I know you've ran a 4150 style manifold for years. Does it have the same benefits as the ITB manifolds that use weber style TB's?

Also I've been wondering how a 3rd gen UIM paired with a S5 n/a lower would do.It would retain the supercharging effect but get rid of all the mess that is the S5 UIM/VDI. Don't know what the runner length would be but it has to be shorter than a S5. I just started learning to weld, I may have to one day fab an adapter piece that would connect the two manifolds and add in the locations for the secondary injectors and fuel rail. Could be a lot of work for nothing. Only reason I ask is I heard there are REW's with the turbos removed making over 200whp. I know the REW has much better ports to start with but how much would that setup help a 6port 13B?

peejay 11-25-18 03:32 PM

The "supercharging effect" is mostly the too-late port closing wasting energy pumping air back up the runner.

Shainiac 11-28-18 02:15 PM

Seeing all you grumpy old men bicker made me remember how friendly and fun RX7club used to be :rolleyes:

BLUE TII 11-28-18 04:18 PM


Shainiac

Seeing all you grumpy old men bicker made me remember how friendly and fun RX7club used to be :rolleyes:
:dunno:
Is this an accidental reply to another thread because of the "related thread" business?
Because I don't see any bickering.

Perhaps you don't understand old man humor?


If all you care about is power, then fark it, throw a V8 in it or a turbo or nitrous (all same heresies IMO) and go drag racing or doing burnouts around a corner or whatever it is that people who only care about max power will do. Probably vape and play Xbox and put ketchup on hotdogs and all the other horrible things in the world. If you want a responsive engine that makes driving the chassis with the throttle easy, then ITBs are the only answer.
This is as close to bickering as I saw, but I would classify it as a mock rant. It had this old man rolling on the floor laughing my ass off.

Listen...
E production racing
Allows naturally aspirated RX-7s
Allows any fuel injection if it uses a (modified) stock intake manifold
Allows carburetor and any intake manifold
Everyone uses carburetors and non stock intake manifolds because it makes more power
Carburetors don't make more power than fuel injection

You want to make power NA its not going to be easy- learn from what others have done.

180rwhp is about peak on a stock port 6 port engine with aftermarket intake manifold/exhaust/etc

Put the vape down and use both hands to type in your searches and you can find a wealth of information. I suggest using Google to search and "rx7club.com" prefacing your searches as the forum search engine is terrible.

peejay 11-28-18 04:51 PM


Originally Posted by Shainiac (Post 12316257)
Seeing all you grumpy old men bicker made me remember how friendly and fun RX7club used to be :rolleyes:


This IS friendly and fun. Relax, you have nothing to worry about.

We're professionals.

BLUE TII 11-28-18 05:13 PM


peejay
We're professionals.
GET OFF MY LAWN!

https://www.safetysign.com/images/so...ages/F7368.png

fidelity101 11-30-18 01:55 PM

what time is bingo?

j9fd3s 11-30-18 04:10 PM


Originally Posted by fidelity101 (Post 12316660)
what time is bingo?

4:30! n00b!


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