So.... am I delusional for hoping/thinking I can maintain my factory idle "control" and 5/6 port while making ~350rwhp reliably?*

Most people I've seen delete the AWS, thermowax, etc. As far as the 5/6 port seems like most people wire them open, mod a turbo LIM, or just use turbo irons when they rebuild.

*It will turbo charged (added later for clarification)

 

Yes, and here's why based on all the reading I have done here and elsewhere on making n/a power. The S5 n/a manifold maxes out at 200rwhp. Also you'll have to switch to a standalone ecu to make that but I think you could keep the 5/6 port functional but not sure. It would really help to have a streetport to get you there but there are some ITS race cars making right at 200 on stock ports( rule don't allow porting). Also from what I read 6 port irons aren't good for much over 200rwhp either so you'd need to switch to turbo irons, and a different intake manifold. This also will require a custom exhaust and tuning of primary lengths of said exhaust. All that and you're still under 250rwhp. For your 350rwhp that peripheral port or monster Bridgeport territory both of which are probably closer to 300rwhp. Someone else can correct me if I'm wrong. Spend some time looking/ searching around here: https://www.rx7club.com/naturally-as...nce-forum-220/

Basically if you want that kind of power go turbo. Unless you have deep pockets , another car for your daily driver, and want to do it for the challenge.

 

Sorry i should've been more specific this isn't an N/A build it will be turbo. I've been looking through build threads, reading technical articles about the port timing of the N/A 13b's, and trying to research the limitations as much as possible for quite some time. I've just been left with the question is it not being done because it's not possible/safe or just because there's no interest in keeping these systems in place.
My FB will be staying N/A and that'll be my daily, but this S5 will be driven regularly.

 

the turbo is difficult to package with the NA intakes, so most people don't

hopefully everyone by now is running a BAC valve though

 

Well that changes everything. I do recall reading a thread, but it's been years where someone kept the 5/6 ports functional when they turbo'd a n/a. Other than that life seems easier to port match the turbo LIM to the 6 port irons or just use turbo irons.

 

I have read that on multiple "N/A-T" threads that the actuators, or the shape of the LIM itself make it challenging to fit the turbo. I wonder if that can be negated simply by taking it into consideration when fabbing the turbo manifold.

 

I can see that through the many people who go that route. Maybe its my ignorance but I wonder if at, what I think is a fairly modest power goal, there is something to be lost/gained by retaining the 5/6 port, VDI, and the idle control

 

Just in case you haven't seen it before. Here is Aaron Cake's info on mounting the turbo using the n/a intake. It's pretty tight and you have to notch the frame but doable.

The (Almost) Complete Guide To Turbocharging The Naturally Aspirated Second Generation RX-7 - Installing The Turbo

 

Here you go. I managed to find that thread: https://www.rx7club.com/2nd-generati...tions-1102581/ Looks like he was using the old Cartech kit. Not sure anyone has done it using the spacer method. Maybe if you fabbed on from scratch you could make it work.

 

As far as physically using the NA manifold and irons, its just a matter of extra fabrication. You aren't going to get much boost into those high compression rotors, but you'd be able to do some, and squeeze more by using E85, race gas, meth injection, etc.

However, anything you do to make that kind of power means:
A) You have to use a standalone ECU, and that means good idle control is totally achievable (with the original BAC even).
B) The original 6 port controls will not function as they originally did, and you will have to engineer a solution. Obvious options are wire them back, plumb manifold pressure to them and let your boost pressure run the actuators, or use an electric solenoid driven by your standalone to actuate the ports at a given RPM.

6p motors without 6p actuation are pretty **** poor at low RPM, so I am going for a more complex solution on a mate's car (Not turbo, but has high flow exhaust) that will involve proportionally driving a stepper motor, in relation to a variable rpm signal, using an Arduino.

These are surmountable problems to be sure, but are also major reasons for not attempting to turbo an NA. Let your wallet and level of motivation decide.

 

Ok I'm back the car and I both survived the hurricane. Dak thanks for the links. I have seen Aaroncake's guide but find it good to reference back to it.

 

I recently acquired a MS3Pro for a good price. I figured there was no way what I wanted to do would be achievable with a factory ECU. I'm still doing some research as to how I can use the MS3Pro to control the VDI and 5/6 port actuation.

I have also been looking through the dyno and time sheets section and have seen a few Turbo II putting down ~350whp at around 14-17psi. I've also seen a few high compression turbo builds making similar numbers.However its hard to compare my situation to theirs considering all the other variables that could come into play.

I was planning on buying one of the 13b stud kits, and am in the process of searching for which apex seals would work best for my application. I will not be rebuilding my engine, because I just don't have the time, so I will be dropping off my engine to be built for me.

 

the S5 uses positive pressure from the air pump and two solenoids, the VDI is just rpm based. the 6pi are actually airflow based, but RPM works ok too.

if you have a turbo, positive pressure is really easy. the FD has a tank that stores pressure, so you could run that, and then you'd have stored pressure to open the 6pi and VDI whenever its needed.

since the turbo changes the VDI and 6 port tuning, you'd have to come up with your own, but its easy, you make a (dyno) run with the 6pi closed, and then one with them open, and lay the graphs on top of each other, where they cross is where it should open. VDI is the same.

 

That's good to know. Any idea what the tank is called? I was looking through the Archives & FAQ but didn't see anything about it in the 3rd gen section.

This is seeming more and more like it could work, reliably...

 

Yes, you can do this.

There's zero reason to remove idle controls at all. And since you are using a standalone, it can control the BAC. You can actually ditch the thermowax as a good standalone can perform all those functions via the BAC. Same with the dashpot. Ends up cleaning the throttle body up a bit and less things to have to tune around.

As for the aux ports, you will need to build a custom manifold to space the turbo away from them. This is actually what I have done with my Cosmo. After that, the actuators can be plumbed to a boost source and a solenoid used to activate them.