2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Removing The Airflow Meter? Hp gains??

Thread Tools
 
Search this Thread
 
Old Dec 31, 2002 | 03:53 PM
  #1  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Removing The Airflow Meter? Hp gains??

Ok I have heard a lot of people say that the air flow meter is very ristrictive and is the major bottleneck in the intake system. That said I also know that you can remove it but that you have to replace the stock ecu with an aftermarket one because the stock one wont opperate poperly without it and the car wont run correctly. I would like to know how much of a performance boost doing this will get me? What aftermarket ecu's are best? What the reliability is on them? Any downsides? and pricing?

Oh, and if a non grease monkey like me can do it myself?
Thanks guys!
Reply
Old Dec 31, 2002 | 03:59 PM
  #2  
Pinfield357's Avatar
Rotary Enthusiast
Tenured Member 15 Years
 
Joined: Sep 2001
Posts: 1,417
Likes: 0
From: Pittsburgh Pa
basically form what you said i would tell you to do other things first just getting a haltech is very expensive then you need it installed if your not feeling up to working with the elsctronics of your car. also youll need to pay to have it tuned on a dyno. do some other simple bolt ones first.
Reply
Old Dec 31, 2002 | 04:11 PM
  #3  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
well I amplanning on adding a true dual exhaust and getting a better flowing fuel pump so I don't run lean and blow the seals but I don't know what other bolt-ons are available but I am also planning on removin the smog stuff and the a/c stuff but I an gong to keep the power steering for now.
Reply
Old Dec 31, 2002 | 04:12 PM
  #4  
Rotorific's Avatar
I dont know a damn thing
Tenured Member 10 Years
iTrader: (1)
 
Joined: May 2001
Posts: 1,703
Likes: 1
From: Evans, Ga
You will need to either get a crash course on tuning an EMS or get someone that knows how to do it. If you dont have a heavily modded motor then putting up the cash for an EMS isnt really worth it. -Gabe
Reply
Old Dec 31, 2002 | 04:36 PM
  #5  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
well I am planning to do some street porting and I want to research on getting some s5 rotors but I dont want to go to far because she is my daily driver. I just want to know how much I would gain by doing this I don't care about the cost because I have a challenge that was proposed to me by a friend about who can beat whobut both of us are going to mod our cars over a couple of years and then go head to head. I don't really mind the green just loosing but I don't want to drive a peripheral ported engine around for a year or six months and then have the engine blow up on me.
Reply
Old Dec 31, 2002 | 05:17 PM
  #6  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Does anyone kno what kind of performance boost I would get regardless of practicality
Reply
Old Dec 31, 2002 | 06:00 PM
  #7  
Aaron Cake's Avatar
Engine, Not Motor
Tenured Member: 20 Years
iTrader: (1)
 
Joined: Feb 2001
Posts: 29,798
Likes: 128
From: London, Ontario, Canada
The power boost does not really come from removing the AFM, but from the fine tuning an aftermarket ECU will allow. The AFM is not much of a restriction until you start getting into high (>350HP) levels. With an aftermarket ECU, you can expect about a 20% power gain over stock.
Reply
Old Dec 31, 2002 | 06:23 PM
  #8  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
But it would still give similar results if the car is mostly stock or no?

my goal is to get to 200rwhp and I have been looking at my options sofar I want to get a full dual exhaust from mazdatrix or find a used one somewhere and add more fuel with a better fuel pump and some bigger injectors proly. I have been doing some calculous and I estimate my rwhp right now as fully stock to be like 115hp plus the numbers that mazdatrix says their exhaust can put out is 28% rwhp on a stock engine which is 32.20rwhp
if the number you just gave me is correct I can proly get 29rwhp out of that proly a little less but that puts me at about 176rwhp a 24hp short of my goal but if my engine ever blows I plan on doing a street port on it. Hopefully that will get me to 200hp at the wheels.
Reply
Old Dec 31, 2002 | 06:25 PM
  #9  
nonameo's Avatar
**-P I drive a miata.
Tenured Member 05 Years
 
Joined: Jul 2002
Posts: 1,600
Likes: 0
From: albany, GA
weight reduction!!!
Reply
Old Dec 31, 2002 | 06:30 PM
  #10  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
I also plan to do that but I like the sound of "I got 200 ponies at the wheels and I am going to kick your 350z ***" I just think it is cool sounding. but I am running without a spare cuz my car did not come with one when I bought it so that must be a few lbs off but I usually have a 124lb girl friend in the pass. seat.
Reply
Old Dec 31, 2002 | 06:41 PM
  #11  
Aaron Cake's Avatar
Engine, Not Motor
Tenured Member: 20 Years
iTrader: (1)
 
Joined: Feb 2001
Posts: 29,798
Likes: 128
From: London, Ontario, Canada
A complete aftermarket ECU (such as the Haltec) won't do you a lot of good until the car is nicely modded. That means open intake, open exhaust, emissions removal and some porting. You MIGHT get to 200HP with a streetport and a Haltec, but it will be CLOSE. You're trying to make 60 more HP in a stock 146 HP engine. The Mazdatrix full dual is most beneficial in a ported engine, and it's doubtfull that you will see the HP gains they claim in a stock port S4 engine.
Reply
Old Dec 31, 2002 | 06:55 PM
  #12  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
What is an estimate on a haltec install and some dyno time.

I think this is what I want to do with my car.

1. The exhaust although $1300 is a lot I will have it an I am willing to spend it.(get rid of my air pump acv and a/c and probobly get an electric fan and maybe thos underdrive pullies)
2. "Cold air intake" I think I might go with an HKS
3. Get a better fuel pump and some bigger secondaries
4. Lighten the car (lightweight seats, remove most of the carpet and insulation stuff, getting rid of the stereo stuff right now, cf hood fenders)
5. suspension work(definitly need new shoxs springs bigger sway bars some strut bars new bushings
6 saftey stuff will probably be added before most of the other stuff also
Reply
Old Dec 31, 2002 | 07:04 PM
  #13  
Bambam7's Avatar
I came, I saw, I boosted.
Tenured Member 10 Years
 
Joined: Apr 2001
Posts: 1,921
Likes: 0
From: Windsor, Ontario, Canada
There isn't really much point on getting a haltech on an N/A unless you are going to go for a full race car, and need to get the most from a specific race class or something.
For the money you are going to spend (1200 bucks for just the computer) plus all the bolt ons (and porting... a waste of money on everything if you don't port)
You are looking at several G's.....
You might as well just put in a turbo motor for half the price, and get twice the power, for 3/8's the headache!!
Reply
Old Dec 31, 2002 | 07:14 PM
  #14  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
what bolt-ons in the future i probably will port and I do want the most hp with good drivability and an engine that doesn't pop in 6 months to a year and perhaps the turbo thing is true but I was challenged in my 1987 N/a SE modle which I have right now. If I just don't want to deal with upgrading an N/A I would have bought an FD and killed his *** a month ago. You guys hear have never heard of principle or what? wtf the guys on this forum always say if you want easy buy a mustang or whatever other V-8 powered car and that is the end of it but being different is what it is all about and that is why we have RX-7's I like N/a's and turbos the same and know that turbos make more power duhh but it is principle that makes me want to beat my friend in a race with the car he challenged me in.
Reply
Old Dec 31, 2002 | 07:33 PM
  #15  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Is it possible to use an intercooler if the car is an N/a?
would it give any good gains if possible
Reply
Old Dec 31, 2002 | 07:49 PM
  #16  
Rotary Freak
Tenured Member 05 Years
 
Joined: Apr 2002
Posts: 1,739
Likes: 0
From: Boulder, CO
don't get bigger injectors if you don't have an aftermarket ECU, or at least an S-AFC or your car will run rich and not make as much power, N/A's run better slightly lean. What octane gas do you use?
Reply
Old Dec 31, 2002 | 11:30 PM
  #17  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
87octane

What is the function of the "S-AFC"
Reply
Old Dec 31, 2002 | 11:50 PM
  #18  
hybridracer's Avatar
I Post In The Nude
Tenured Member 10 Years
 
Joined: Feb 2002
Posts: 1,289
Likes: 0
From: College Station
Its a piggyback fuel computer that tricks your ECU into thinking its getting more or less air thus leaning or richining(is that a word?) your A/F mixture.
Reply
Old Dec 31, 2002 | 11:58 PM
  #19  
Rotary Freak
Tenured Member 05 Years
 
Joined: Apr 2002
Posts: 1,739
Likes: 0
From: Boulder, CO
its an air/fuel ratio controller. you controll it.
Reply
Old Jan 1, 2003 | 12:02 AM
  #20  
Turblown's Avatar
Turn up the boost
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (12)
 
Joined: Dec 2001
Posts: 7,174
Likes: 236
From: Twin Cities, MN
You won't need bigger injectors or a fuel pump on an N/A. So don't waste your money. If your serious the Haltech is nice, and ppl make it a lot scarier than it really is, I'm not to hot on electronics, beyong the basics, And its very straight forward and EASY! and I have the flying lead harness, get the terminated harness and it will be even easier. Best bet would be to get your motor rebuilt and a Huge streetport, if not a bridgeport. An intercooler will do no good on an n/a. Hks has the worst intake design, just buy the intake adapter and a universal K&N, save your self some cash. Get some underive pulleys, convert to manual steering rack, no ac or emissions, an E-fan. Port your intake manifolds, do the TB mod, full exhaust. You should do some research on exhaust, there is a lot do it, and its designs. When you have the motor rebuilt, have s5 rotors put in, T2 rotor housings, and there are some other nice stuff too, FD opr etc. Lighten the hell out of the car too. Good luck with the project, and would nitrous be cheating for you?
__________________
Rotary Performance Parts


Reply
Old Jan 1, 2003 | 12:12 AM
  #21  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
no but it is lame when you run out isn't it?
Reply
Old Jan 1, 2003 | 12:13 AM
  #22  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
1Revvin7


thanks for the positive attitude a rare thing these days on the forum (at least as long as I have been hear)
Reply
Old Jan 1, 2003 | 12:40 AM
  #23  
Evil Aviator's Avatar
Rotorhead
Tenured Member 15 Years
 
Joined: Feb 2001
Posts: 9,136
Likes: 39
From: Charlottesville, Virginia, USA
Originally posted by 1987RX7guy
What is an estimate on a haltec install and some dyno time.
$500 - $3,000 for the install and tuning. This is in addition to the $1,000 to $1,700 for the EMS. Although I think that some of the other posts underestimate the value of an aftermarket EMS, it is absolutely more cost effective to sell your NA car and buy a TII for $500-1,000 more than what your NA is worth.

Originally posted by 1987RX7guy
1. The exhaust although $1300 is a lot I will have it an I am willing to spend it.(get rid of my air pump acv and a/c and probobly get an electric fan and maybe thos underdrive pullies)
2. "Cold air intake" I think I might go with an HKS
3. Get a better fuel pump and some bigger secondaries
4. Lighten the car (lightweight seats, remove most of the carpet and insulation stuff, getting rid of the stereo stuff right now, cf hood fenders)
5. suspension work(definitly need new shoxs springs bigger sway bars some strut bars new bushings
6 saftey stuff will probably be added before most of the other stuff also
1) Depending on your state emissions laws, you may be able to just use a Racing Beat uncollected header, a good muffler, and some cheap muffler pipe to get what you want for a lot less than $1300. I would put the money saved into a manual steering rack if you currently have power steering, as this not only has less drag on the engine, but also handles better in my opinion.
2) I didn't like the HKS system on my TII. I think that a K&N cone with a simple heat deflector would work better, and would cost less than half as much as the HKS system.
3) The stock fuel system should work fairly well with an aftermarket ECU. Fuel upgrades are only a crisis for modified TII's.
4) Yes, lighten the car!!! This will give you the most performance gains.
5) Suspension costs big bucks. For a full all-out street suspension you are looking at over $2,000. You may not want to replace anything until it is actually worn.
6) Safety stuff is also big bucks. A ballistic blanket and driveshaft hoop are always good, but I think that you don't need a whole lot of saftey mods with only 200 hp.

Originally posted by 1987RX7guy
Is it possible to use an intercooler if the car is an N/a?
would it give any good gains if possible
Air to air intercoolers cannot make the intake air any cooler than the outside air temperature, and most are only 60-80% efficient anyway. Turbos heat the air as they compress it, which is why an intercooler works well. Your NA has no turbo to compress and heat the air, so an air-air intercooler does you no good, and would only end up as a restriction (ie pressure drop).

An air-liquid intercooler with an ice chest can cool your intake air colder than the outside air, but I don't think it's worth the cost, weight, and pressure drop to use one on your NA.
Reply
Old Jan 1, 2003 | 12:53 AM
  #24  
1987RX7guy's Avatar
Thread Starter
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Evil Aviator

I would like to thank you for your input.(maybe I should hang out with the mods more)
1. your probably right but I don't know any good mufler shops around here and I dunno how to weld so I have to do some more research on that
2. I was on e-bay right now and a lot of those kits are like 60 bucks so that is a better idea.
3. I had no idea that this problem was with TII's only but thanks for pointing that out that is some nice savings you just gave me
5. The suspension is pretty much gone as far as the springs and I want to lower it too.
6. I was thinking more along the lines of some helmets and 5-6poin harneses and some mini fire exstinguishers

thax for the info on the intercoolers!

Thanks again dude youre a lot better than 80% of the guys on hear (clicks buddy list) I appreciate it.
Reply
Old Jan 1, 2003 | 12:54 AM
  #25  
dr0x's Avatar
pei > caek
Tenured Member 05 Years
 
Joined: May 2002
Posts: 4,643
Likes: 0
From: Mars
Re: Removing The Airflow Meter? Hp gains??

Originally posted by 1987RX7guy
But it would still give similar results if the car is mostly stock or no?

my goal is to get to 200rwhp and I have been looking at my options sofar I want to get a full dual exhaust from mazdatrix or find a used one somewhere and add more fuel with a better fuel pump and some bigger injectors proly. I have been doing some calculous and I estimate my rwhp right now as fully stock to be like 115hp plus the numbers that mazdatrix says their exhaust can put out is 28% rwhp on a stock engine which is 32.20rwhp
if the number you just gave me is correct I can proly get 29rwhp out of that proly a little less but that puts me at about 176rwhp a 24hp short of my goal but if my engine ever blows I plan on doing a street port on it. Hopefully that will get me to 200hp at the wheels.
Get a nitrous express wet kit. Good for upto 125hp or so (before you go direct port). Major torque. If you want to beat him and keep your car and not dump 4k into it, nitrous is your answer
Reply



All times are GMT -5. The time now is 06:09 PM.