Take it for a A TUNE UP!! a thousand dollars worth of mods isnt gonna do nearly as much as it should if the car isnt runnung right!!

 

Either that, or you just Cant drive.....

 

I agree with Tesla042 that you could have a clogged exhaust. I have had this happen on my first RX-7 (1st gen), I (being new to RX-7's at the time), had some cheap muffler shop put on a cheap "high flow" cat on it.... worked beautifully for about 2 days, then my car started going slower, and slower.... pretty soon I was flooring it just to keep up with traffic... put in new cat, problem solved.
I would highly recommend looking into replacing that, that could totally solve your problem right there

 

This sounds like where I was with my car about three years ago... I dumped thousands on every little thing I though would make the car go faster, with no real results. IE:

MSD-6A: Waste of $140 bucks, smoothed out the idle, did nothing for power.

Plug Wires: $70 for magnacore. no gains.

Electric Fan: Another Waste of $200. Drains your battery and eventually caused the death of my original engine. Gained maybe 1-2 HP. not worth it.

Under Drive Pullies: Ran my alternator and water pump slower, which accelerated the problem with the electric fan.

You want a fast NA? Take notes...
1) Start with a good block. The 86-88 NA block is sturdy, but doesn't take bolt on modifications well. You opened up the exhaust and intake on your project, but the block is still the restriction. The best NA block is the 89-91 with the VDI setup. You get lighter rotating assembly, higher compression, and an 8000 RPM redline stock! (If you balance the engine and upgrade the oil system you'll be good to 9000 RPM easily = expensive) Porting the 89-91 block provides a good foundation for a fast NA.

2) Intake/Exhaust: You've got this covered... Header, silencer, cat back of your choice. Done. Cold air box and cone filter. You could also upgrade the 86-88 AFM to the 89-91 AFM for better flow.

3) Fuel: Like several people have mentioned, getting a Super AFC can help tune that puppy in. The stock injectors can handle most bolt on modifications. Leaning out the mix in the middle range will provide substantial gains. (Mazda was very conservative with the factory settings)

4) Timing: Bump the timing up to 8-10 degrees of advance to see more top end power.

5) Operational 6-ports and VDI: Use an electric air pump with RPM switches to open them. Get the MODIFIED 6-port sleeves from http://www.pineappleracing.com/

With the 89-91 NA block at this level of mods, you'll easily see 175-180 RWHP. (Assuming the engine block is fresh) Probably more depending on the quality of the rebuild.

You want more?
5) Rear end: Swap the 4.1 rear gear for the GTUs 4.3 gear.

6) Transmission: Swap 1st, 2nd, and 3rd gears for 84-85 GSL-SE gears. This provides even faster acceleration, but just be ready to shift very fast!

This where I'm at now...

 

First off- What do you consider fast?? Sorry, I've driven tons of s4 and s5 N/A's, and the s4's just don't seem to have guts at all.. The S5 n/a's, are the only ones (IMO) that you can get up to a respectable speed (no more than a street port)

Definatly check your compression.... if that's down, you car WILL be slow.

Pull the 6 port sleeves out, port the intake manifold, get the $50 pinapple sleeves.

ALso- bigger rims can DEFINATLY make the car slower... When I went from stock 15's, to TII 16's, with 225's on them, I was surpised at the loss of low end power...

The S-AFC can get you a good 1/2 second off your 1/4 run too.... you can find them used for $200 or so...

Do you have traction?? Are you spinning tires?

Before you look at anything else though- check the compression.. if it's bad, tear the engine apart and do a street port while you're at it!!

 

Could you produce some dyno run sheet that prove this "fact"?


-Ted

 

id say your engine may need some assistance.

do compression check. maybe do the ATF trick. worked wonders on my car i could feel such a power surge after that.

when you take off the line you should be feeling the car pull a little extra at about 3500 or so, then about 5000 you should be feeling a surge of power as the runners switch over. it should pull like that almost to redline. if your not getting that kind of reaction let us know.

 

Did I say "Fact" anywhere? It's all opinion! My opinion on the MSD-6A is that it provides very little gain for the money spent. The stock ignition handles the job very well for NA applications.

I'll have dyno sheets of my current setup in the next month or so... Trying to schedule an appointment at K&D Rotary as we speak.

 

Okay, so you based your conclusion of "did nothing on power" on your opinion?


-Ted

 

wozzoom - Is it your opinion that you'll be getting 175-180 RWHP with all those mods listed or do you have some dyno sheet to prove it? There has been no one on the forum prove they can get that on a stock block N/A 13B engine. One person did get a lillte over 160HP and that was on a series 4 engine with a series 5 N/A intake. Most of the ppl that produced a dyno sheet got about 120-140. I'm not trying to put you down, we just want to see a dyno sheet for proof. You've been on the forum long enough to know what I'm talking about. If your talking about a ported engine then those numbers are doable and I stand corrected.

Peace

 

Yes he did mention porting the Engine so thsoe numbers may be accurate, a Dyno still looks better though.

 

Highly unlikely if you are still using the stock AFM, I doubt this is going to happen...................specially when the word easily is mention!

 

Agreed. Its all talk until you produce a dyno sheet. For the record I am talking about a ported motor. The most I could ever get out of a stock 86 block with bolt on mods was 146 RWHP. My new engine has only been in my car for three weeks. I'm still in the break in period... The dyno run will be coming as soon as I can get an appointment.

As for the AFM being a restriction, I'm running the 91 AFM with my 86 ECU. I guess the only way to get any better than that would be to go Haltek?

I based my CLAIM of 175-180 RWHP on dyno sheets provided by John Zanol. His 89 GTUs broke 180 RWHP with a ported engine, header, no cat, N1 Single, Super-AFC and 550 injectors in the secondaries. I haven't heard from him in awhile...is he still on the list?

 

Yes Ted. My OPINION is that adding an MSD box is not worth the money when upgrading an series 4-5 NA. No I do not have any dyno runs of before and after I added my MSD box. Butt dyno only.

Now could an MSD box by itself give you a subtantial HP gain? possibly.

Could my butt dyno not be sensitive enough to notice this gain? possibly.

Is spending $140 dollars on a MSD box going to make your car faster? not likely.

My post was meant as a short list to get NA power. without NOS. Sure an MSD box is a relatively cheap mod compared to a new series 5 block, BUT is it worth it?

Obviously you have evidence that contidicts my opinion, otherwise you wouldn't be hounding this point. Care to share?

 

you know that never did help the guy who posted this!!!
he wants to know what might be wrong not what you opninion or pissing constests!

 

I run Crane Cams HI-6 in all my cars, and there is a definite increase in power on dyno run.&nbsp Sorry, I don't have those sheets in front of me, but if anything the car runs a more consistent top-end (i.e. no ignition break-up like most stock ignitions have at high RPM).&nbsp The Crane Cams HI-6 is similar to the MSD 6A (series), so gains should be similar; a more equivalent unit from MSD is the Digital-6+.&nbsp NA's typical show a 1-2hp gain across the entire RPM band; most people's "butt dyno" can't feel that difference - some can.&nbsp Else, the CDI box is defective or installed wrong.


-Ted

 

This keeps coming up despite the number of times it gets shot down. It can'y be done without swapping the ECU, which would mean swapping everything else as well. And the difference in flow would be minimal. The S5 one may have less internal pressure drop, but it's inlet is only ~60mm dia. compared to the S4's 60x50mm inlet, so there's hardly any difference. Oh, so you've done this?

 

Yes. I have had the S5 AFM in my car for over a year. Works great. If there is enough interest in this mod, I'll start another thread with the wiring directions.

 

Here is how to install the series 5 AFM in a series 4 car

 

Wozzoom's car is fast for a NA Trust me.
He stays up with my slightly modded 90t2 rather well.
I should know, we just did it last night.

 

it says in your description that you removed the smog pump.. but you still have your cat. MAYBE you should check to make sure your cat isn't plugged (hint hint)

 

The wiring's the easy bit, there's nothing to that. But the two AFM's have different output characteristics. The airflow/movement relationship is logarithmic for a flapper type an close to linear for a slider type. That's why I mentioned the ECU. Have you dyno'd the car before and after to see if there was any power increase (doubt it) or change in mixtures (guarantee it)?

 

Comparing my dyno runs of my car before and after the AFM install is not going to be accurate because I'm running different engine blocks... (Unported vs. Ported)

Yes, the Linear vs. Logarithmic arguement has been made in past posts and it is agreed that the S4 and S5 AFM meters do indeed have different output characteristics. The question of how the output of the S5 AFM is interpreted by the S4 ECU is the question that was never answered or tested.

From my INFORMAL testing there has been no change in the performce of my engine. Fuel economy has remained constant, spark plugs have a dull beige color, and there is no hesitation/pinging in the powerband...

Dyno results with a wideband are on the way. I'll know more about my A/F mix then.

 

^^^ guess that never happened....