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-   -   t2 housings n/a internals (https://rotarycarclub.com/showthread.php?t=3181)

86-rx7 07-20-2008 10:36 PM

t2 housings n/a internals
 
so i am wondering can i use t2 housing and put in n/a internals. I just bought a parts car that came with a extra t2 motor and i want to stick to n/a and was thinking about porting out the t2 motor hopefully for some more power out of a n/a. Also would i have to use the t2 tranny as well since i am using t2 housings as well. Any help of what i would need or should do would be great thanks

vex 07-21-2008 05:52 AM

Quote:

Originally Posted by 86-rx7 (Post 35032)
so i am wondering can i use t2 housing and put in n/a internals. I just bought a parts car that came with a extra t2 motor and i want to stick to n/a and was thinking about porting out the t2 motor hopefully for some more power out of a n/a. Also would i have to use the t2 tranny as well since i am using t2 housings as well. Any help of what i would need or should do would be great thanks

Wait... Let me make sure I understand you correctly. You have a 6-port 13B (That's the N/A) and you have a 4-Port 13B (that's the Turbo). You are not planning on using a turbo, but want more power from your NA?

If that is the case, then no (-Ted). What you're attempting to do is asinine and will not yeild you dramatic results, if any improvement at all. One major reason is that your NA has 6-Port Induction (6PI). Two of which are put on a valve system (of sorts) that allows you to have low end torque without sacraficing your highend horsepower. If you switch over to the 4-port motor you will lose the 6PI which will result in a loss of low end torque and marginal if at all gains up top (depending on port job). There really is no improved benifit to switch the rotor housings, Irons, and the rest of the motor from a T2 onto an NA rotating assembly and remaining NA. If you were planning on turbo charging your engine, then that would be a different story. You'd have all the ability to run a turbo, and still have high compression rotors.

My5ABaby 07-21-2008 06:31 AM

Kahren on the other forum ran a S4 TII block with S5 TII internals to 186whp as an N/A setup. Of course it was on a standalone, exhaust, etc.

http://www.rx7club.com/showthread.ph...ht=port+kahren

So it's possible, but I wouldn't. I would just trade/sell the TII engine for an N/A one.

Whizbang 07-21-2008 08:19 AM

actually, i have to "beg to differ".

We just finished assembly of a 13b with S4 9.4:1 rotors and S4 turbo irons. Running on an Megasquirt unit and a distributor.

The thing is, the 6pi end plates can not make the power a 4 port ones can. Porting everything to flow well and maintain a desirable velocity and have your choice of port timing is easily done on the 4 port. But the 6 ports are basically the opposite of this.

I say go for it! I'm starting to stray away from turbochargers when i can. Its a huge step up in complexity and money with the benefits of a shorter life span.

Whizbang 07-21-2008 08:21 AM

Quote:

Originally Posted by vex (Post 35053)
Wait... Let me make sure I understand you correctly. You have a 6-port 13B (That's the N/A) and you have a 4-Port 13B (that's the Turbo). You are not planning on using a turbo, but want more power from your NA?

If that is the case, then no (-Ted). What you're attempting to do is asinine and will not yeild you dramatic results, if any improvement at all. One major reason is that your NA has 6-Port Induction (6PI). Two of which are put on a valve system (of sorts) that allows you to have low end torque without sacraficing your highend horsepower. If you switch over to the 4-port motor you will lose the 6PI which will result in a loss of low end torque and marginal if at all gains up top (depending on port job). There really is no improved benifit to switch the rotor housings, Irons, and the rest of the motor from a T2 onto an NA rotating assembly and remaining NA. If you were planning on turbo charging your engine, then that would be a different story. You'd have all the ability to run a turbo, and still have high compression rotors.

Then explain Logan's 13b-Re n/a that makes more hp than any 6pi ever will.

vex 07-21-2008 09:38 AM

Quote:

Originally Posted by Low Impedance (Post 35066)
Then explain Logan's 13b-Re n/a that makes more hp than any 6pi ever will.

How's that tuning ;) Think about it. Stock you have a rich and non-aggressive timing map. Looking strictly at the engines themselves:

The velocity at the low end will not leave a good torque curve let alone you had to port the 4-port to get to the same amount of intake area, right? Add to that if you're going to be porting the Tii you might as well port the 6-port and have a larger intake area with a finer control on volume (assuming you're leaving the 6pi intact).

Lets look at it another way. Assuming that the stats from the previous post are accurate at that the hp of the modified engine on a standalone is 186hp whp with S5 internals lets compare how they do to the S5 NA which produces 160hp, for sake of argument we'll assume that it loses 20hp and only produces 140whp. That's a 46hp defeciet that it would have to make up right? How much hp can you pick up by adjusting the fuel curve and spark? You can get a butt load. I can honestly see picking up 50-60hp with a standalone. Why? Because you lose some of the most restrictive portions of the intake and you can tune for power instead of fuel economy. 1) you lose the AFM providing less restriction on for the engines intake. 2) you can lean or richen the fuel to make the approriate AFR 3) you can retard and advance the spark to where the power is.

Is that not accurate?

classicauto 07-21-2008 10:37 AM

well, if by housings you mean just hte housings themselves and not the irons, the nsure, you'll make more power on the TII housings given that they don't have the divider/diffuser in the exhaust ports (the diffuser can be removed from the N/A housing BTW....)

Using the TII housings and irons you'll still end up with nearly the same peak horsepower as demonstrated by a few different cars in the past, Karhen's mostly. Either way, either N/A setup is going to come in under 200whp in most cases. Logan from defined autoworks cranked out a little over 200whp after alot of tweaking, but still to assume less than or in/around 200whp is reasonable.

Only way to really push much beyond that is with some more radical porting, or the addition of extra oxygen to the chamber (N20 or boost). It just seems to be the limitation of the volume of combustion....even look at renesis engines. Stock Mazda claimed "240bhp" but testing proved that to be inflated. IIRC the highest renesis dyno I've seen is a little over 200whp..........still within a mere few ponies of the setups discussed earlier.

Having full control over the engine is great, but still won't be enough to overcome the physics of the amount of air and fuel requried for number much beyond 200 without (as mentioned) bridge/p poritng or nitrous/turbo

EDIT: You won't need the TII transmission unless you use the TII flywheel. You'll need to make a choice on that one as if you decide to use the TII flywheel.trans you'll either need the adapter (TII Trans ---> N/A diff) driveshaft from Mazdatrix or the rest of the TII drivetrain.

86-rx7 07-21-2008 11:21 AM

well my motor runs strong in the car i was just thinking about it because i have 3 other motors and was asking if it woulld be even worth it. i know that the max power i can even hope for would be under 200 hp more like 180 or so. I was just thinking about it and thought i would toss my idea out there because some one might have done it and could shed some light for me. If i would need a standalone i will stay away from it because of money reasons maybe later. Like i said i was just curious about the idea.

My5ABaby 07-21-2008 11:56 AM

Quote:

Originally Posted by vex (Post 35075)
Lets look at it another way. Assuming that the stats from the previous post are accurate at that the hp of the modified engine on a standalone is 186hp whp with S5 internals lets compare how they do to the S5 NA which produces 160hp, for sake of argument we'll assume that it loses 20hp and only produces 140whp. That's a 46hp defeciet that it would have to make up right? How much hp can you pick up by adjusting the fuel curve and spark? You can get a butt load. I can honestly see picking up 50-60hp with a standalone. Why? Because you lose some of the most restrictive portions of the intake and you can tune for power instead of fuel economy. 1) you lose the AFM providing less restriction on for the engines intake. 2) you can lean or richen the fuel to make the approriate AFR 3) you can retard and advance the spark to where the power is.

Is that not accurate?

Apparently the 186whp was on a conservative tune. If that makes a difference. :D

vex 07-21-2008 12:03 PM

Quote:

Originally Posted by My5ABaby (Post 35094)
Apparently the 186whp was on a conservative tune. If that makes a difference. :D

Do we know if he was using the S5 intake manifold or was it custom? (I haven't even factored in the other modifications that may have been done to the motor)

Whizbang 07-21-2008 12:07 PM

i believe it was the RE manifolds.

My5ABaby 07-21-2008 12:13 PM

http://www.rx7club.com/showthread.php?t=380348

Quote:

Stock intake with filter on TB

vex 07-21-2008 12:48 PM

Doing a quick glance over his set up, he's not using NA rotating internals. He's pushing 9.0:1 (S5 Tii) and making the 186hp with a full exhaust, intake, and tune. Not to mention larger injectors and a bigger pump.

knowing that he's not using NA rotors then he's obviously making up for the power in other locations, IE: Fuel, Timing, Intake Manifold, Porting, Exhaust, etc. He's not going to make that kind of power without a tune or the supporting modifications, so what I said still holds true. You will see little if at all increase in HP and a worse torque curve only swapping the Housings and Irons (leaving the rest stock. That includes: Fuel, Timing, Exhaust, and Intake).

Whizbang 07-21-2008 12:52 PM

well i pm'ed GTo7 to give his thoughts on the 13b-re setup he has. Better to just hear it from the horse's mouth.

vex 07-21-2008 12:53 PM

Quote:

Originally Posted by Low Impedance (Post 35106)
well i pm'ed GTo7 to give his thoughts on the 13b-re setup he has. Better to just hear it from the horse's mouth.

Very true. Better than my in-experienced ass trying to figure it out.

GtoRx7 07-21-2008 03:20 PM

Hey this is Logan, I was linked by low impedance. Its always a large debate on 6-port vs. 4-port n/a. I personally feel the 4 port is the way of making power easily, and cheaply. The irons are not expensive, and a used standalone is very cheap as well. Here is my setup of the RE-
Stock upper and lower intake manifold from the 13b-re. Medium sized port, S5 rotors, not ideal header at the time. 1st gen distributer, haltech F10a fuel only computer, 3" k+n filter. MSD box, with second gen coil for leading. Electric fan. 206rwhp with 152rwtq. The power under the curve is great, making more torque at even 1500rpm than a stock GSL-SE. If you guys have any other questions, let me know. I like the forum, so I will be hanging around now :)

85rx-7gsl-se 07-21-2008 03:49 PM

^Welcome GTO and thanks for the info.

vex 07-21-2008 03:55 PM

Quote:

Originally Posted by GtoRx7 (Post 35130)
Hey this is Logan, I was linked by low impedance. Its always a large debate on 6-port vs. 4-port n/a. I personally feel the 4 port is the way of making power easily, and cheaply. The irons are not expensive, and a used standalone is very cheap as well. Here is my setup of the RE-
Stock upper and lower intake manifold from the 13b-re. Medium sized port, S5 rotors, not ideal header at the time. 1st gen distributer, haltech F10a fuel only computer, 3" k+n filter. MSD box, with second gen coil for leading. Electric fan. 206rwhp with 152rwtq. The power under the curve is great, making more torque at even 1500rpm than a stock GSL-SE. If you guys have any other questions, let me know. I like the forum, so I will be hanging around now :)

I'm a little curious about your setup, your running a fuel computer and an MSD ignition, what are your injector/pump sizes? Are you running S5 NA rotors? I ask as I'm curious to know if this is indicitive of the tune or if it's other modifications (including the port job/irons/housings). If it's more indicitive of the tune then that's saying something about the stock NA engines and how much power might be available to them with a standalone.

GtoRx7 07-21-2008 10:26 PM

Quote:

Originally Posted by vex (Post 35141)
I'm a little curious about your setup, your running a fuel computer and an MSD ignition, what are your injector/pump sizes? Are you running S5 NA rotors? I ask as I'm curious to know if this is indicitive of the tune or if it's other modifications (including the port job/irons/housings). If it's more indicitive of the tune then that's saying something about the stock NA engines and how much power might be available to them with a standalone.

I am using the 550cc injectors that came with the RE engine. But I dont really count injector size helping with power. Even the 460cc injectors will support enough Hp in n/a form, possibly make more power from the SMALLER injectors, but that is another subject. The fuel pump was upgraded to a msd/walbro style, the stock GSL-SE pump was "almost" there. I did install Series 5 n/a rotors. I would really like to have direct ignition that the FC has stock, as that alone would possibly net 5+ rwhp or more. But I built it on a very tight string budget, and got the old F10a haltech for $100. Its hard for me to plunk down $1k on this car for ignition control :).

I know for a fact that a S5 n/a 6-port will not gain 50-60rwhp from a standalone install. I would love to think so, but its not possible. The AFM is not super restrictive, a loss of 5-10hp is pretty realistic. Tuning and timing will net another 10-20 or so. I would love for someone with a 6-port to prove me wrong, but they require so much work to get there. The 4 port of any type produces 180+rwhp with so little work. And its hard to make less than 170rwhp even with a stock exhaust mani, and 9.0:1 rotors. In my opinion the 6-port just cant do this.

85rx-7gsl-se 07-21-2008 10:45 PM

So 4 really is greater than 6, go figure...

4>6 :lol:

vex 07-22-2008 05:46 AM

Quote:

Originally Posted by GtoRx7 (Post 35197)
I am using the 550cc injectors that came with the RE engine. But I dont really count injector size helping with power. Even the 460cc injectors will support enough Hp in n/a form, possibly make more power from the SMALLER injectors, but that is another subject. The fuel pump was upgraded to a msd/walbro style, the stock GSL-SE pump was "almost" there. I did install Series 5 n/a rotors. I would really like to have direct ignition that the FC has stock, as that alone would possibly net 5+ rwhp or more. But I built it on a very tight string budget, and got the old F10a haltech for $100. Its hard for me to plunk down $1k on this car for ignition control :).

I know for a fact that a S5 n/a 6-port will not gain 50-60rwhp from a standalone install. I would love to think so, but its not possible. The AFM is not super restrictive, a loss of 5-10hp is pretty realistic. Tuning and timing will net another 10-20 or so. I would love for someone with a 6-port to prove me wrong, but they require so much work to get there. The 4 port of any type produces 180+rwhp with so little work. And its hard to make less than 170rwhp even with a stock exhaust mani, and 9.0:1 rotors. In my opinion the 6-port just cant do this.

It seems a little odd that Mazda would invest time and money into a system that was less capable when a 4-port can make more power and better torque throughout the RPM band. You'd think that they would have had this information upfront and saved time and money with only producing one set of housings. Seems completely counter intuitive. Guess I should pick up an RTek V2 and see what I can get the stock system up to...

Whizbang 07-22-2008 08:13 AM

on the other hand, auto manufacturers aren't looking at just power output.

Once you start porting engines, playing with tuning etc, the fuel economy, drive-ibility, reliability, etc change. Emissions comes into play. The switch from the 4 port 13b to the 6 port 13b was probably just a function of the above. Plus Mazda seems to enjoy experimenting with new ideas.

vex 07-22-2008 08:23 AM

Quote:

Originally Posted by Low Impedance (Post 35260)
on the other hand, auto manufacturers aren't looking at just power output.

Once you start porting engines, playing with tuning etc, the fuel economy, drive-ibility, reliability, etc change. Emissions comes into play. The switch from the 4 port 13b to the 6 port 13b was probably just a function of the above. Plus Mazda seems to enjoy experimenting with new ideas.

That's true, but a street port shouldn't adversly affect those to the point of failure. The regular NA has 3 cats to pass US emission standards. The only difference I can actually see with regards to the engine is the 6pi and their only function is to increase low end torque. I'd like to see a dyno chart of a 4port na compared to a 6 port na and look specifically at their torque curve (below the 3500 rpm mark).

Whizbang 07-22-2008 08:47 AM

but stock, the ports are rather small as opposed to an a medium to large street port. Porting generally does bad things to most forms of e-check.

TehMonkay 07-22-2008 09:03 AM

Emissions, fuel economy, driveability.

People who race high power turbo hondas dont need vtec either, it's just there for driveability, from the factory.

GtoRx7 07-22-2008 09:18 AM

Quote:

Originally Posted by Low Impedance (Post 35260)
on the other hand, auto manufacturers aren't looking at just power output.

Once you start porting engines, playing with tuning etc, the fuel economy, drive-ibility, reliability, etc change. Emissions comes into play. The switch from the 4 port 13b to the 6 port 13b was probably just a function of the above. Plus Mazda seems to enjoy experimenting with new ideas.

Couldnt say it better myself. Performance vs. Stock, and the changes needed between the two are so different. Torque between 1000-3000rpms is SO important to mazda in a factory car. If my engine had to have full cats, air pump, etc it would have less torque in this area without a doubt.

86-rx7 07-22-2008 09:17 PM

so from what i am geting it can be better you just need to be able to tune it right and have the housing ported. it might suffer a little down low but up high it would gain some. Am i correct so it would be almost fesible to do it and see would i would gain or lose. I am just going to be tinkering around with the motors and seeing what would even be able to be reused.

vex 07-23-2008 05:35 AM

Out of curiosity does anyone have a side by side comparison between the 6 port stock and the 4 port stock (the ports on the irons specifically). I'm curious because I know you can port the 6-port to be much bigger than the 4-port (but you end up killing the intake velocity), but I'm thinking that the 4-port is in a better position for more extreme porting with less negatives associated with it.

Whizbang 07-23-2008 07:39 AM

i might be able to do so in comparing a 12a four port to a GSLSE, and/or S4 6 port. I only have a turbo center iron.

vex 07-23-2008 09:15 AM

Quote:

Originally Posted by Low Impedance (Post 35462)
i might be able to do so in comparing a 12a four port to a GSLSE, and/or S4 6 port. I only have a turbo center iron.

If you could snap a picture of a direct view of the ports at the same distance that would be great. I'm thinking maybe individually taking the pictures of the ports at 1.5-2ft out on a tripod, then replacing the iron in the same location so we get a little bit of accuracy on the ports (that way one won't appear bigger than the other, etc).

My thinking is that the "no-no" spots or the limits of porting are the same location for the 4 port and 6 port, but I may be mistaken on that.

Whizbang 07-23-2008 09:37 AM

i could take a picture side by side and then take measurements with a mircometer

TehMonkay 07-23-2008 01:09 PM

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

that is only for the center though.

Whizbang 07-23-2008 01:14 PM

huh, well that is neat.

vex 07-23-2008 04:12 PM

That's pretty cool. We'd still need to look at the end irons though for their passageways. I'm assuming that the center irons are pretty much the same for both thet NA and Turbo.

Whizbang 07-24-2008 05:59 AM

not necessarily. If there is enough of a difference in the casting of having or not having an EGR, then is a good chance they could have done something in the casting for the ports, especially since the turbo and non turbo may not share the same port timing.


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