Ok i've read some posts on not getting a mp without having a powerfc. I have a stock 93 fd and i was planning on getting a dp and mp....but i've been reading that an mp would not be good on a stock car...why and what are my other options...would just getting a dp for now be better?

 

Do a search for midpipe and boost creep, and I think you'll find your answer.

 

There's lots of info out there. You should definitley get a dp ASAP. It's a no brainer. There is no downstroke since you get better performance and less heat as a bonus.

You should probably consider some other thing before the MP. Intake and Cat Back for one. Then revisit the issue depending on what you want. If you don't have what I just mentioned save the MP until after you get those things, and an ECU to boot.

 

a midpipe is one of the last things that you should get

you can't have a midpipe on with the stock ecu because the main cat is so restrictive and adding a straight through 3" pipe lets so much more air flow and adds boost and hp that your stock ecu can't handle.

Without an upgraded ecu you can get the downpipe though

next you could get a catback and intake but you are pushing the limits of the stock ecu and on a cold night you might run 12 psi with those mods at full throttle and run lean which could cause the motor to blow. A boost controller with the boost set to 10psi and those 3 mods will be very safe and also add hp and reliability and reduce temps and flow without raising the boost.

If I were you I would get a boost gauge, water temp gauge, downpipe and do the fan mod right away.

ps there are many ems' out there except for the pfc

there have also been many many many topics about midpipes and order of mods and if you would have searched a little harder you would have found what I just told you plus a bunch of other opinions and details.

 

alright so save the mp for later and just get the dp and a catback. I'd really like to get an ecu...but gotta save the money first. I will say...i got a really good deal on my car 30k on engine and turbos...104k on car...only thing wrong with the car...the glove box lid wouldn't shut haha...only paid $9000 for the car =)
thanks for the info guys

 

you dont need a powerfc to run a midpipe, but on your stock fd i would say go with the downpipe and a good exhaust,get a midpipe later on down the line,when you go midpipe you start to encounter boost spikes and boost creep,to controll these you will need a ecu upgrade, does not have to be powerfc and a good boost controller hope this helps.

 

Just FYI, an ECU upgrade alone isn't going to control boost spike/creep.

It can provide additional fuel for higher boost levels, but if you are having boost creep, and ECU isn't going to stop that.

 

i mentioned to him to buy a good boost controller to take care of that problem.

 

In case you don't know what boost creap is, here is a copy-and-paste from this thread:
When you open up your exhaust, you turbo system will be dealing with more exhaust. Part of your turbo system is something called the wastegate. The wastegate diverts exhaust away from your turbines so that they don't deliver as much pressure to your intake. However, if your wastegate is too small, then your turbines will be spinning faster and faster as your revs increase, even when the wastegate is completely open. This is referred to as "boost creep". If you boost creeps too high, then you will pop your engine. Porting (enlargening) your wastegate will prevent this, because it will be able to handle the extra exhaust that comes with exhaust upgrades. Another option you have is a "restrictor plate". A restrictor plate is a plate with a hole in it, that you put between either your downpipe and midpipe or your midpipe and catback. The hole in the plate is smaller than the diameter of your exhaust, so that it restricts the flow of exhaust so that the wastegate isn't overloaded. This should just be a temporary mod, while you are waiting to port your wastegate.


If I were you, I'd get a DP, boost gauge, and eliminate the AST.

 

thanks for that post...this is all good info...now i have something to discuss with jerry b4 i get him to start working on my car...i'm just trying to get all my options out on the table b4 i spend money on something then change it after a month...such as...i don't wanna buy a high flow cat...and than after a few mods...go back and buy a mp...thanks again...keep the suggestions coming

 

Read the post by JONSKI, above.

If the wastegate is overrun, a boost controller can't do squat. You should REALLY check out the following thread:

https://www.rx7club.com/forum/showth...threadid=26389

 

hmm good thread...ok...so what would you guys say (considering my stock setup) getting a dp, mp, and temporarily having the restrictor plates put in and possibly having the wastegate ported?...Also...how much trouble is it to have your wastegate ported? Once again...this is stuff i can discuss with my mechanic now...but your opinions would be nice too..thx

 

I would suggest that you not mess with a midpipe at this stage. It's pretty clear that you need to do a little more research (not trying to slam/flame you) about the problems that can arise after adding a midpipe.

I would suggest a hi-flo cat first (actually, I would really suggest leaving the main cat alone unless it's clogged and just do the dp and catback). Down the line if you still want a midpipe, hopefully by then you'll be ready to deal with possible problems like boost creep.

 

yea that's what i was thinking too...but the guy working on my car thinks that the cat might be clogged...he ran a boost guage to my car and did a test run...and it's showing really low boost...all the way around....so his first recommendation...was to put in a dp and a hiflo cat and see if that caused the problem...does that make sense...clogged exhaust make low boost pressures?

 

Yes, definitely that's a possibility. However, there are many other things that could cause low boost. Do you know exactly what your boost pattern is?

If he wants to "test" it and use a hi-flo cat, it wouldn't hurt anything. However, unless you know for sure that it's the problem, I wouldn't pay for him to jack around with the car.

 

no he's an rx7 specialist...he charged me nothing to look over the car and test run it...he also told me that it may or may not fix the problem...but that that was a good place to start...but he said we'd take it one thing at a time...i mean i know i need a dp....and if that doesn't do it...he'll change out the centerpipe...etc.