I'm just curious about what kind of HP numbers I can expect from this rebuild I'm doing:

New TII Housings, S5 Irons Lapped, Street Port, S5 Intake, Lightened Race Rotors, Cold air intake, RB Header, 2mm Racing Apex Seals. I think that's most of it.... it will stay N/A for now.

Any ideas??? I want to know if I'll be able to beat my friend's 1990 5L Mustang

Thanks!

 

what are you using for an EMS, and what's done to the mustang?

 

The EMS is stock. The Mustang has fairly high Km's... intake, headers, exhaust... some stuff, but nothing too crazy.

 

More info on these lightened race rotors....like compression and weight. Also what kind of apex seals? Carbon, Ceramic ?

From what I've seen other S5 N/A's dyno with stock ECU, you'll be around 160-170whp?? I think you'd find more gain with a standalone.

 

Thanks, even rough numbers are good. The rotors are 90-92 HC Lightweight rotors, the seals are carbon I believe. So what kind of gains are seen with the standalone.... and how much would it cost?

 

Here's some encouraging info
https://www.rx7club.com/time-slips-dyno-128/na-streetport-6-port-dynoed-182whp-details-inside-416012/

I thought this guy was running a Haltech...d'oh!!
So it seems 180whp is possible with your setup....if its put together properly

 

Ya.... I just don't know if that's fast enough ya know...

 

I need a tubo or supercharger setup I guess.

 

I might just forget about the fancy n/a build... get the JHB cermet coated housing set off of ebay for $675 Canadian (for both) and then rebuild and sell it.... I don't know, I don't like having to make this decision.

 

I've gone for a ride in a fast '91 gxl n/a and it was no slouch!... built engine pretty similar to yours actually now that I think about it.

he isn't on the forum anymore but his name was BamBam_7

 

people have had street ports ranging from just over stock to around 200whp. with NA you really have to pay attention to the details, it's not a simple matter of turning up the boost. if you want to get serious about it, intake manifold and header design become big factors.

if you just want power, go the turbo route. all things being equal it will be easier and cheaper in the end.

oh, and if you are wanting to beat the Mustang on NA power you are going to need to take it to a real track, not a drag strip

 

New TII Housings = 0 extra hp over stock
S5 Irons Lapped = 0 extra hp over stock
Street Port = +10 to 20hp over stock
S5 Intake + Lightened Race Rotors (S5 NA) = ~10 hp over stock
Cold air intake = neglectable
RB Header = ~10 to 15 hp depending on rest of the exhaust
2mm Racing Apex Seals = 0 over stock.

If I were you and want to keep it NA, I would:

Get SDJ header over RB header
Pineapple racing sleeves
Keep S4 NA rotors and invest money on lightweight flywheel + clutch
SAFC to tune fuel

Cheers,
Derek.

 

I'm with PD but with a few changes. We're N/A authorities lol

 

Oh yeah ...

Use GSL-SE or S4 TII transmission for better ratio

 

Our carburated 13B bridgeport made 230HP at the wheels. Then it blew up 5 months later!

 

My Buddy runs a Supercharged 12A making 160whp in his FB. He eats mustangs alive. Hes beat, to my knowledge, 1990 5L, 1996 4.6L Modified, and a 1998 Camaro Z-28.


I know of a GXL (N/A) in Montana that runs 12.7 in the 1/4 Mile and makes just over 200HP at the wheels.


You need over 300HP at the wheels to make a mustang do that. Mustangs (and most muscle cars) are VERY heavy compared to RX-7's.

 

You have to remember that most of the ET in a drag race comes in the 1st few hundred feet. If you have ever watched a top fuel car break at the 60ft mark, then run a 10.77 @ 42 mph you will understand what i mean. The muscle cars make all their time at the start, while the turbo and small displacement cars gain in top end. I can take my 207 rwhp 3500 lbs mustang, put 4.11 gears in it and unhook the front sway bar to run a mid 12 second ET. My 230 rwhp 2200lbs RX-7
wouldnt get close to that because it has no bottom end power and cant launch at 4000RPM without breaking parts

 

I'm pretty sure you can launch an rx7 hard, it just takes practice and a few modifications as far as not-break-stuff goes. Look in the timeslips section on the 2nd gen forum, lots of faster TII's cutting 1.6 and 1.7 60' times without breaking ****. We'll see this summer.

Obviously a mustang with a live axle is a better setup for launching but fast IRS cars do exist.

What you said though was otherwise entirely accurate. 1/4 mile is decided largely by the launch. My POS talon ran a 14.7@ only 7PSI boost (stock is 11) - because it's AWD and launces really well. Lack of horsepower showed up in the top end though - 87mph trap.

 

1.6 - 1.7 60ft times are okay for a street tire, but with a built live axle you can get those to 1.1 - 1.3 and thats where the low ETs come from. I'm sure you can launch your 7 very well, its just the "snap, crackle pop factor id be worried about on a slick or drag radial. Maybe at the end of the year we will take the road race car to Cayuga and see what it will run----but my 4.88 diff is soooo expensive to fix!

 

yeah, once you get off street tires, a live axle is a must. I've seen cars with slicks literaly stick to the pavement after a burnout. so much so that the tow truck was unable to lift them until the tires cooled!

 

where can you get the SDJ header? i can't seem to find the info...

 

I have one =P

You can buy one off ebay from Banzitoyota.

 

Great info.. thanks! I might just rebuild this one n/a and sell it... and then get a turbo sometime down the road.

Or if anyone is interested I might sell it... it's pretty much ready to be rebuilt, it just needs new rotor housings. The body is in great shape... basicall no rust (faded paint though). I bought it October 2004 with 179,000 kms on it. I bought it to fix up for the following spring so I didn't drive it it hat year at all. I basically spent the whole winter fixing little things on it. I put on new rotors, pads and calipers too. I took everything out of the interior to make sure there was no rust in the floor etc. (there wasn't). I then restored the interior, there were things missing that I found on Rx7's at the junk yard etc. I got a brand new dual exhaust put on with new performance mufflers. I also bought a new set of nice Khumo tires, that was $700 by itself. Anyways there's more I just can't remember. So I insured it in the spring, had it on the road for like a week and a seal blew.. sucks for me!

So I took the engine out that spring... realized that there was a groove in the rear housing and I would have to replace the housings. I didn't have the money at the time to get the new housings because I had already put so much into everything else.

So this past winter I got the rebuild kit from Rotary Aviation (about $900 Canadian I think). I thenk prepped pretty much every part... I'm a bit of an **** perfectionist, everything had to be perfect. All parts were cleaned with the die grinder and wire brush, so not one part, bolt or nut has any rust on it. I paited some stuff that needed it with high quality super high temperature enamel. Also, everything is labeled and is in zip-lock bags with the part name and the exact time and date it was take out. Every time I took something out or apart I took a picture so the times can be easily traced to the pictures to make sure I knew how to put it back together. You can now start to undertand the **** part.

So if anyone is intested I might be convinced to sell everything as it is now... ready to be rebuilt. The car was safetied just before the seals went last spring so everything on it is fine.

Good body and interior
Completly new brake rotors, pads and calipers
Brand new exhaust and mufflers
New Catalytic converter
New Khumo sport tires (the car has aftermarket 16" rims that look pretty good)
New fuel pressure regulator
Rebuilt kit... everything there ($900)
Rebuild gasket kit (everything ready to go)
New engine mounts from mazda
New Fuel filter from Mazda
There is basically too many things to list... I've honestly spend a LOT on this car... my estimate is about 6,000 Canadian.

I don't really want to sell it, but I could use the money right now so I thought I would post this just to see if there was any interest. The car has been sitting in a shop all winter so it hasn't been outside or anything like that.

I've included some pics of the car.. but PM if you have any questions or offers etc.

 

nice car!

unfortunatly, blown motor n/a's just aren't worth alot.

turbo swap! Or finish the rebuild and sell it that way if you must sell it.

I'm planning on doing a pretty full season of racing this year and hoping for some pretty quick e.t's with the new turbo/fmic setup. I'm going to be launching pretty hard on DR's.. I'll let you know what breaks if anything does

 

I used to launch at 7000RPM in my FB on DR's.