mor

I just bought a '94 RX-7 that was not running and I'm currently rebuilding it at my friend's shop.

1. Got the rebuild and gasket kit from Rotary Aviation. Watched Bruce's video.
2. I've also purchased two turbo rebuild kits from Turbo City and have already finished rebuilding the turbos.
3. Now, I just got some street port templates from MazdaTrix and am going to do the street port before rebuilding.

The only mod on the car was Apex'i intakes and a Greddy BOV.

Now for my questions, and yes I've been searching through the archives and have learned a lot but still kind of confused.

1. Will I need a EMS with the street port and intake? And most likely a downpipe will be put on before reinstalling the engine.
2. I will end up doing full exhaust (dp, mp, cb). I also want to up the boost a little, what's safe? 13 psi or 15 psi?
3. I understand the fuel tuning. I'm going to get a DIY WB, Datalogit, PFC...but this is later. So at that time will I just make the AFR rich and then use datalogit then lean it out according to the readings?
4. Now the most confusing part. Timing tuning. I have heard to adjust the timing at certain RPMS until it detonates then back up 1 or 2 degrees. Is there any "proper" way to tune timing like the AFR tuning? Or, can I just run the PFC with base maps and adjust AFR to be safe? Or use one of the maps others have that will be similar to my mods, then adjust AFR.

Well, I know this is a long thread so sorry. Please help! Thanks so much!

mor

bump! Are these stupid questions or just unanswerable? =)

es

It's a wierd place to post these questions, but here's my advice.

1. Will I need a EMS with the street port and intake? And most likely a downpipe will be put on before reinstalling the engine.
*I would. The streetport+Intake+Downpipe should be a great street combo, but there will probably be lean conditions at low RPMs & the factory ignition map is designed for stock ports You don't want to risk it...

2. I will end up doing full exhaust (dp, mp, cb). I also want to up the boost a little, what's safe? 13 psi or 15 psi?
*If you do full exhaust you should port the wastegate on your turbos NOW! It's very easy to out flow the WG path which will give you constant boost creep. Also, you need to hunt for restrictor orifices (they are in the hoses that run from the turb snails to the WG & PC actuators). Since your car is a '94 you may have to drill out the nipples on the turbo snails to allow controllable boost (search in the 3rd gen section for turbo pill orifice or PM me & I'll give you pages of details).

3. I understand the fuel tuning. I'm going to get a DIY WB, Datalogit, PFC...but this is later. So at that time will I just make the AFR rich and then use datalogit then lean it out according to the readings?
*Yep. You can simply tune it for an 11:1 A/F on a dyno...

4. Now the most confusing part. Timing tuning. I have heard to adjust the timing at certain RPMS until it detonates then back up 1 or 2 degrees. Is there any "proper" way to tune timing like the AFR tuning? Or, can I just run the PFC with base maps and adjust AFR to be safe? Or use one of the maps others have that will be similar to my mods, then adjust AFR.
*NEVER tune your FD until it detonates. You must have gotten that recomendation from an NA Mustang dude! On ANY forced induction engine you want to stay away from detonation! You have a turbo charged engine now, so take advice from people that have expierence with turbos, Nitrous, & superchargers! Also, you need to be quite a bit more conservative the the DSM, SR20, & 2JZ crowd.

Search through maps of ported motors & pick one that makes sense to you. The base ignition maps are crap IMO, & the XS & SRM maps are slight variations of that!

skotx

You probably didn't get much response because this doesn't really seem like a thread that should be in the Power FC forum. Your questions are kinda non-ECU specific.

1) Downpipe and intake would be fine with the stock ECU. I don't know how a street port affects tuning. You can study some of the available Power FC maps that have ported motors. Best bet is to get the DIY WB ASAP.

2) Keep it under 12 with the stock fuel system.

3) You don't need to mess with timing until you really know what you're doing. Detonation is very very bad for a rotary, so don't tune it the way you suggested. Not a lot of people around here talk about timing tuning. I've heard to check out the single turbo forum for more advanced tuning info.

mor

Thanks for all of your replies. I just figured the tuning questions should belong here but oops, my mistake!

So I guess both of you are recommending the Power FC to be installed NOW because of the street port. I guess I just have to cough up a thousand bucks!

I will port not only the housings but also I will port match both the intake and exhaust manifolds as well. So porting the wastegate will help with the boost creep?

The pill method, that's manual boost control right? Doesn't the Power FC have boost settings? I was going to set two boost settings in the Power FC. So 12 psi on stock fuel system...okay I'll remember that.

As for the timing...so just leaving the base map that Apex'i has is fine as long as I tune the AFR? Is this correct? Or should I use a map that is similar to mine? And will it be safe to run hard with these maps that are SIMILAR but not tuned exactly for my car?

Sorry for so many questions, I just want to do things the right way. I'm almost done with the rebuild and having put so much time and energy into it I really don't feel like doing it again! =) Thanks again!

es

You're getting there. I don't trust the Apexi ignition maps. My opinion, & others will agree with my I'm sure.

Get a Datalogit. Makes the Power FC much more useful, powerful & fun.

The pill(s) isn't manual boost control, it's part of the factory boost control system. If you read through the '93 FSM about the turbo control system you'll find pills exist in the hoses from the front turbo snail outlet to both the PC & WG acutators. Later model cars had this restriction built into the nipples themselves, & you have to drill those out to alow boost levels lower then 14PSI (assuming full exhaust).

You are correct about the WG porting. If you don't do this you'll always boost to 15PSI or more (again assuming full exhaust)!

12PSI is a good boost level, & I would say stay at or below 12 until an intercooler, fuel pump & injector upgrade is performed. IMO those 3 things should be done at the same time. In fact, it would probably be a good idea to throw the Fuel pump in before the IC & Injectors...

Enjoy.
Eric.

mor

Eric,

The pills are already in the hoses on the turbo? Oh crap, when rebuilding the two turbos I also changed the hoses to silicone and I'm not sure what pills you're talking about. Any pics? And if I threw them out...am I in trouble?

Please help, thanks!

es

If you threw them out you're boost pattern would be 7PSI, Dip to 5ish, back to 7PSI & hold to redline.

Unless You're '94 model has the restriction built into the primary turbo snail nipples... This is a VERY good possibilty!
http://www.rx7turboturbo.com/robrobi...controller.htm

That's about the best I can do for pics...

phlanigan

I thought that the Apexi timing maps are a little on the aggressive side in the boost areas. I retarded the spark a little. Some of the threads that I've read mention keeping leading advance to no more than 15 degrees in high rpm/boost areas of the map. I've found that threads by Badog and Beast from the East have quite a bit of info in them (both good and bad), so you could try searching for their posts. Also Nocab seems to have been able to get a lot of power from his engine and I followed his advice when it came to setting ignition split (I chose to keep it around 8-10 degrees) although some on the forum run no split with apparently no ill effects (Rice Racing).

Anyway, I'm only a few months ahead of you in terms of tuning experience, so I can't offer you a lot of firsthand knowledge. I haven't blown my engine yet, so hopefully I'm doing it the right way...

es

Those that run little to no split tend to run less advance & tune their maps via EGT.

mor

I'm a little confused about the pills still. So if they are still installed and I have full exhaust, I will have boost creep.

So drill them out if in the nipple or remove in the hoses.

So won't that cause the 7-5-7 psi pattern then? I'm not sure why I need to mess with these pills. Sorry for the ignorance!

es

No, pills wont give you boost creep, but too small of a pill will give increased boost levels.

The Power FC is much better then the factory ECU in controlling boost, so you could probably just tune your boost level by it vs: drilling the pills.

mor

Okay, I'm going to leave the freaken' pills alone for now...if I even still have them. I looked in the two nipples on the turbo snails yesterday and don't see anything noticeable in them (not sure what to look for anyway). And if the pills were in my hoses...oh well they're gone, I'll know once I drive it.

As for the wastegate porting. I have everything apart. Which side is it on? The engine side half of the manifold or the turbo assembly half? And what exactly am I porting and to what degree?

On the turbo assembly, there's a small circle wastegate that doesn't look like it can be openned much. To the right of it is an opening where the flap closes and I could possibly take out a tiny bit on the lower right corner but that's it. Am I looking at the right places?

mor

Is this what needs to be ported? If so, how much of a lip should I leave around it?

mor

Image is here:

http://morlanliu.netfirms.com/rx7/wastegate.html

es

Yep, that's the WG. Open it up as much as you can while still allowing the door to fully (or near to fully) cover the port when closed. Also pay attention to the flow direction & try to take off material that would create turbulance to that flow.

Also be sure to make a slight radius to the WG lip. Sharp corners crack easier then radiused edges.

mor

Thanks es for all you help. I ported the wastegate, not too aggressively though, I left about 1/8" smaller than the flap. Is that not enough porting? I already reinstalled the turbo assembly and don't want to open again.

Also, I checked the nipples and the restrictors aren't in there so I'm guessing I threw them out. So with out them I'll run 7-5-7 psi. So I should do Rob's manual boost controller then right? If so, I'm scared about the pre-control tuning (boost spike). Where should I start? All the way closed pre-control and all the way open wastegate? I feel safe about the boost control...just don't want to blow my brand new motor tuning the pre-control.

es

You welcome. 1/8" should do pretty good, but I personally went as big as I could go. Like 1/16" & made sure to cut away anything that looked like it could interfere with the flow direction. Also I tried to put a radius at all of the edges to slow the manifold cracking.

I wouldn't start with the PC all the way closed, but cracked, & just keep opening it until the dip at transition is quick, but not spiking...

mor

Okay, makes me feel better. Don't have to open up that damn turbo assembly again.

Well, since I have to break-in the motor for 1000 miles. Is it safe for me to just drive without any pills in either wastegate or pre-control hoses? I'll do the manual boost controller later then.

Also, what do you think I should expect from street port, intake, dp, cb, and y-pipe @ 12psi? Horsepower wise. This will be my daily driver and if that's already really fast then I won't be doing much else to it.

And also, with those mods mentioned above. Do you think a Apex S-AFC will be sufficient instead of the Power FC. If the S-AFC is all I need then I will just tune the AFR and not mess with the timing at all. My goals aren't as aggressive as most people. Your advice is much appreciated.

es

Yes running it without pills is fine, & is actually a good way to lower boost on the stock turbos.

SP+Intake+DP+CB@12PSI That should get you around 300 or more at the wheels with a good tune.

I don't like the S-AFC. It raises the fuel percentage by supplying a falsely high boost sensor voltage to the ECU. That's fine as long as the ECU can compensate for the boost levels it thinks it's seeing. The FD ECU will fuel cut if it see's boost levels over 12PSI (lower then that before 3500RPM).

The Power FC also gives you air temp correction control, ignition control, & the ability to run larger injectors, & with a datalogit the ability to change the fan temps, & logging capability.