Sgtblue

iTrader: (16)

Yep, I think everyone is in agreement that it's his absolute right to do with the car what he wants. But otherwise this is hollow statement. If it's tasteless, self-destructive to the car, dumb or just plain silly, he should know people will be shaking their heads or snickering and he might get his feelings hurt.

rowdog_14

So do a good amount of stuff last night. Checking the vacuum lines I noticed one the plastic nipples on one of the solenoids is broken off and attached to the check valve hose. I added pictures. Looks like I am going to have to replace that . Also I noticed that two metal lines do not have anything on them, I added pictures of those too. Looking at the vacuum hose FAQ I think they are just open to the air...is that correct what I am seeing?

Banzai-Racing

iTrader: (11)

The unused metal lines are for the automatic. The broken nipple is a problem, it looks like it is the one that is most forward and the bottom, which controls the double throttle.

rowdog_14

Thanks for the info, yes it is the most forward bottom one solenoid. Will look into getting that fixed going to be fun. Probably will just replace all those hoses under there while I am at it.

Also I ordered a downpipe from you guys looks like it will be a little while. Will put it on as soon as I get it

rowdog_14

Found a leak on the rear turbo.

rowdog_14

Removed the pan below the trans and found a small leak on one of the trans pans bolts.

Took the car for a drive after a late night maintenance and no more hesitation at 3k and 4500k! This sucker is pulling smooth now!!! Get these last two leaks fixed and that one broken vacuum line from the post above and just wait until my down pipe comes in from Banzai.

kensin

iTrader: (22)

what was the maintenance you did to fix the hesitation problem ? great car btw looks stunning !

rowdog_14

Well lol, but I will tell you prior to even posting here I had a long list of items I wanted to take care of. I think it may have been either the EGR valve or a boost leak on the y-pipe and crossover. All know now is after capping the EGR valve and cleaning the connection boots and tightening then down the car runs like a bat out of h-ll . I personally think it was the y-pipe

Thanks for the complement on the car. Last night moving the car I tagged the rear bumper of my wife car. 99% of the time always park in Neutral and last night I park in our driveway which is steep, so I put in gear+Ebrake just to be on the safe side. Went to start the car let off the clutch and it went under the wife bumper lol. two small dings on the hood and a scratch. Will get some touch up paint and pull out my paintless dent repair and see how much of the dent I can pull out. Really not bad though.

Sgtblue

iTrader: (16)

It's been a while but IIRC the two biggest things to reduce hesitation on the stock ECU twins was to clean and supplement grounds and always wait to boost on a fully warmed up engine.

rowdog_14

Yep the ground update was going to be one of my upgrades but seems like that was not an issue for me. I am still going to do the ground update though. I warm up all my cars even the daily beater...I was still getting bad hesitation at 3k and around 4500k which made me believe it was something else beside the ground.

Seems the trans leak is fixed after changing the fluids and tightening the bolts back down. I will give it a few days and see, if not I will drain the fluid replace the gasket and refill back up. Really happy how things are going but I will say adding the fluid back in was a pain even with a pump .

I have a few things left on my list but main things are bleed brakes and install the gauges and I will stay off of it until I get the down pipe, y-pipe, new AST, and cat back exhaust.

Montego

iTrader: (1)

My $0.02...

1. Down Pipe - Yep I used the Rx-7 store brand and it served me well
2. Cat-Back - My preference is racing beat. Love the sound and how low key it is
3. Mid-Pipe - RESONATED is a must
4. AST Tank - I prefer deletion of that infernal thing.
5. Rear window spoiler - Your car, your choice
6. Duck Tail spoiler - Your car, your choice
7. Mazda RX-7 JP USA Vizage Body Kit - 7PC or just do a R1 front lip - my preference is the R1 lip or 99 lip
8. Gauges(Boost, Temp, Oil Pressure, Fuel Pressure, AFR(last gauge since I am not modified) - Only the boost gauge, the others are unecessary for this level of mods
9. Wheels - A must!
10. Y Pipe - waste of money
11. Modify Stock Airbox - Good mod
12. Boost Controller - To control boost given that you will have exhaust mods
13. Ported Wastegate - If go the full exhaust route, you will very likely require a ported wastegate
14. Upgrade SMIC - the stock unit really sucks

1. Apexi Power FC - Unless you are planning to boost past 10 psi otherwise leave well enough alone
2. Turbo Timer(Is this even needed if not modified heavily?) - RICER MOD *always* no matter the level of mods

MOBEONER

iTrader: (18)

If you are a new FD owner you will be curious and eventually get tunnel vision wanting more mods and more power. For some of us who have been in the rotary game for a while have learned (sometimes the hard way) that simple is always better. a guy with a mostly stock rx7 gets to drive and enjoy the car a whole lot more that those of who chase horse power numbers.

rowdog_14

Took the car to a big car show here in Atlanta,GA and people could not believe it was a stock car even down to the muffler

BLUE TII

iTrader: (9)

Sorry to quote all that when it is right above.
This list is possible DANGER ZONE if you have any other cat back besides the restrictive Racing Beat catback. It will likely run very lean AFRs in the high RPMs on the stock ECU.

I did just maintenance items, new Denso fuel pump, downpipe, high flow catted muffled midpipe, catback, Y-pipe, smallest SR motorsports stock mount IC and MBCs to keep boost at 10psi and it was running high 12s to low 13s AFRs on the stock ECU in the high load high RPM areas.

My stock AFRs were in the high 9s and low 10s AFR at high load high RPM by the way. That is what Mazda considered safe.

My previous mod list which was same as the above but with stock main cat was what I considered safe enough on high load high RPM AFRs (ran high 11s low 12s).

My safe list on stock ECU would be-

1. Down Pipe - Yep, removes common point of failure
2. Cat-Back - Yes, its fun.
3. Mid-Pipe - NO. Stock cat assembly only on stock ECU!
4. AST Tank - Yep, removes common point of failure
5. Rear window spoiler - Your car, your choice <-- agree.
6. Duck Tail spoiler - Your car, your choice <-- agree.
7. Mazda RX-7 JP USA Vizage Body Kit - 7PC or just do a R1 front lip - Drive it stock a while and see if the gorgeous stock lines don't grow on you. Especially with some wheel fitment.
8. Gauges(Boost, Temp, Oil Pressure, Fuel Pressure, AFR(last gauge since I am not modified) - Only the boost gauge, the others are unecessary for this level of mod <-- agree.
9. Wheels - A must! <-- agree, even if I hate the wheels you choose.
10. Y Pipe - waste of money <-- I like the metal Y pipe. Eliminates a point of failure, looks and flows better than the plastic piece. No downside besides the reasonable cost.
11. Modify Stock Airbox - Good mod <-- agree. Do not do any aftermarket intakes on stock ECU, they will cause lean AFRs in high load high RPM.
12. Boost Controller - To control boost given that you will have exhaust mods <-- agree. I like Hallman MBCs on prespool and wastegate for perfect smooth 2ndary transition.
13. Ported Wastegate - If go the full exhaust route, you will very likely require a ported wastegate <-- agree. If the turbo are off, port the wastegate.
14. Upgrade SMIC - the stock unit really sucks <-- agree.2. Turbo Timer(Is this even needed if not modified heavily?) - RICER MOD *always* no matter the level of mods <-- agree. Ricer or racer mod only.

Sgtblue

iTrader: (16)

Yeah curious Montego, why don’t you like the efini Y pipe?
Also, just for clarification, wouldn’t the BC be needed to avoid spike when the INTAKE is opened up? AFAIK it doesn’t do anything for creep from EXAUST mods.

BLUE TII

iTrader: (9)

Boost control does affect "creep" on the FD because the stock ECU boost control is closed loop and does not reference actual boost pressure in any way.
It just cycles the solenoids at the rate that was required for a good boost pattern with all the 100% stock restrictive intake, exhaust, IC, etc.

Stock FD boost "control" is just ******* crazy town!

I raced in stock class one year and just the allowed drop in K&N and straight-pipe cat-back was enough to send the stock boost "control" into hysterics and have boost spikes, terrible 2ndary transition and boost cut on the 2ndary turbo in any gear above 2nd because of the stock ECU "10psi" boost limit.

From an earlier owner's Mazda service records of my FD all the way back from 1997 when the straight-pipe cat-back (Looong time auto-x car) was added I saw he was in the dealer several times for these exact issues which they were unable to fix and correctly contributed to the non-stock cat-back.

rowdog_14

I ordered an Efini Y-Pipe but was on back order. So they cancelled it out and since my car is running much better I think I could hold off on it for a while or not get it at all. I also ordered a R1 front lip yesterday, the factory one on mine is cracked so decided to just upgrade that. Probably going to pass on the body kit just because I really at this point do not want to mess with it. I picked up a unused rear window spoiler for cheep and it looks horrible(kills the lines of the car), it was not the one I wanted but for the price I said what the heck. So no more window spoiler for me . I did see a ducktail in person at the car show on another RX7 and it looked good. Will probably still get that down the road.

So all I have left to do is get a RB cat back, install the gauges and tint my windows and I will be happy. At some point probably upgrade the intercooler to a stock mount if I come across a good deal and upgrade the radiator if I come across a good deal. With all the feedback I got at the car show keeping it mostly stock like I wanted will be a better eye catcher. One guy was even amazed that it did not have tint and had the factory exhaust. This is a fun car to drive in its stock form!! Took it up to 100 with a buddy and I was only in 4th gear around 5.5k, he was like dang you still have 3 grand left and another gear!!!!!

Montego

iTrader: (1)

Actually that is a very common misconception. Wade back in the day ran multiple lambda tests and he proved that the stock ECU runs rich enough to support all boltons at 10 psi. I may add he did a proper test, and had his equipment verified to assure that his readings were correct. I should also note that I ran for YEARS with a stock ECU, MP and WOT every change I got. The caveat was that I kept my boost rock solid at 10 psi. Not 10.5 ect...

That is very interesting. So what were the conditions of your data? What was the flow rate of your injectors? Duty cycle? Did you verify that the AFR gauge was reading properly? And if you did, how did you go about it? What about your boost gauge? Did you verify it as well? Was the boost solid at 10 lbs or was it closer to 11 say 10.9 ish lbs?

Considering boost is controlled properly at a solid 10 lbs: Please elaborate how a midpipe affects AFR's.


It is not that I don't like it, I mean it looks great polished but it doesn't do much as far as reliability. It's not like our stock Y pipes are known to pop off. Nevermind, that the next component down the line (IC) is joined by a coupler

That is correct. I want to mention that a BC is used to control two things, elevated boost and boost spikes due free flowing mods. Note that boost creep is =! elevated boost. Also correct that a BC will do nothing for boost creep as it is a function of the wastegate being out flowed by the exhaust modifications. As you know, the way to correct that is to simply port it the wastegate.

arghx

iTrader: (3)

Let me warn you. Any part of the interior you remove is highly likely to break. If you pull the door panels to install tint, they will never go back on like they were from the factory. They will never be right again, and you can't get new ones. They might rattle more, or some plastic will crack, or any number of things. If you pull something off, have a replacement part handy, or be ready with the hot glue gun. All the plastic clips are at risk for breaking for example.

Gauges are overrated on a mostly stock car. If you need to diagnose a boost problem you can temporarily install a boost gauge, without drilling holes into panels. Once you go down the road of a new ECU or messing with the stock boost control system you will have to constantly monitor it. Boost changes with the weather etc. Stock boost control system is the most reliable as long as you stay close to stock level of exhaust restriction. Of course it's going to run poorly if you open the exhaust up on stock ECU. That's typical for any boosted car with an open exhaust and stock tune.

The stock coolant temperature gauge is fine. It tells you when you are too cold and it tells you when you are too hot. There are millions and millions and millions of cars on the road with the non-linear stock gauge. If your cooling system is maintained and you'll be fine. If you are racing that's a different situation.

BLUE TII

iTrader: (9)

Instead of answering each point you made I will address this one question as it reflects what you don't understand about why we had two different results following a similar path.

Anything you do to de-restrict the intake or exhaust affects the engine Volumetric Efficiency even when held at the exact same boost pressure. More air in, more fuel needed.

This is the weak point when modifying a vehicle like the FD RX-7 that uses Manifold Absolute Pressure as the load input to the ECU and the ECU just looks up fuel and ignition tables for its stock engine Volumetric Efficiency to suite the boost pressure reported by the MAP sensor.

The Racing Beat cat back is a very effective restriction that limits the engine VE, so with your set-up you did not run lean on the high end RPMs.

I did not have a Racing Beat cat-back, but instead a 3.5" cat-back therefore I had to use the stock cat as the very effective restriction to limit the engine VE.

eslai

Wait wait wait--are you telling me there's no knock control or fuel cut on the Power FC? I didn't realize that. I was hoping to install one someday on my car even with it being mostly stock, just so I could smooth out the boost spike and other fine tuning.

cib24

On the PFC there is overboost control but it's a straight fuel cut whereas I think the stock ECU is an ignition cut? Someone correct me on that last point.

The overboost protection however is about 0.3 bar above your set boost level. So, if you set the PFC for 10 PSI boost but you spike then the fuel cut from the PFC will kick in around 14.5 PSI. So, you better have enough fuel in the car at the sensitive points of the map (transition area on the twins and upper end of the RPM range) for 14.5 PSI in case you spike that bad before the PFC fuel cut kicks in. Usually you never spike quite that much but I made sure my map is nice and rich for most of it in all honesty just in case. I don't care if I might lose 5-10 hp.

Montego

iTrader: (1)

I do that's why I asked about the validity of the equipment that you based your results on. So basically the answer is no to my questions and therefore maybe your injectors were lacking a bit, or your boost gauge was off (I've had that happen), or your O^2 sensor was not reading quite right. I don't know but I do know that unless the equipment used to take measurements is validated, then any conclusion based solely on those results should be taken lightly. Do you agree or disagree?

No offense but that did not answer how a midpipe affects AFR's (if boost is kept at a constant 10psi). Let me try this another way: You stated that a MP is a no-no because he will lean out. Ok so I am asking you to please explain how a midpipe increases the AIR going into the intake stroke of the engine provided the boost remains constant.

arghx

iTrader: (3)

Reduced backpressure can reduce the residual gas content that dilutes the intake charge air. It's easier to evacuate the combustion chamber during the exhaust stroke.

So with less inert exhaust gas carried into the intake stroke, there is more room for combustible fresh air. Combustible fresh air requires more fuel mass in order to maintain the appropriate air fuel ratio.

Sgtblue

iTrader: (16)

Edit...I THINK