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-   -   What's the most HP you could get with a N/A? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/whats-most-hp-you-could-get-n-14020/)

Ryde _Or_Die 08-07-01 12:14 AM

What's the most HP you could get with a N/A?
 
I was just wonderin the most HP u can get with a N/A w/o addin a turbo or supercharger or even takin the engine out? And wut would the mods be & wut kind of 1/4 mi could i expect? Thanks.



Chris

mazdaspeed7 08-07-01 12:22 AM

On a stock port, the limit is probably 240-250 hp, but that is with every bolt on possible. Im pretty close to that on my car.

Current mod list:
cone filter
TB mod
ported intake manifold
RB dual outlet headers-->straight pipes all
the way to the mufflers
all emissions removed, including air pump
6 port sleeves removed
electric fan
UD pulleys, main and alternator
TII fuel pump and 550 cc secondaries
A/c and p/s removed
Crane Hi-6
NGK plug wires
timing advanced
some weight reduction...~2600 lbs
Redline ~8500 rpm

That puts me at about 230 bhp. I am doing the Mustang MAF sensor conversion as soon as I get the schematics for it. Other than that, theres not really anything else I can do without opening up my motor or doing forced induction.

rxspeed87 08-07-01 03:49 AM

hey mazda speed when you get that mustang MAF let me know man
I going wanting get more power on my own N/A here
how much of a diff did the manifold port make on your car?
also what would you say for exhuast
N1 dual with header and downpipe. or the true dual like what mazda trix sells

cash money 08-07-01 03:55 AM

i didn't know you could put a downpipe on an N/A

rxspeed87 08-07-01 03:58 AM

hey mazda speed when you get that mustang MAF let me know man
I going wanting get more power on my own N/A here
how much of a diff did the manifold port make on your car?
also what would you say for exhuast
N1 dual with header and downpipe. or the true dual like what mazda trix sells

RETed 08-07-01 07:24 AM

I highly doubt you could hit 200hp to the wheels with the stock ports, period.&nbsp I'd like to see dyno runs of such a beast if you're going to brag about such numbers.

I've seen ported motors not even hit 200hp to the wheels with stock computers.&nbsp It's possible a stand-alone on a ported motor could break the magical 200hp to the wheels barrier.

Most people would agree that even a (street) ported motor would be hard pressed to break 220 to the wheels with everything you threw at it short of making the engine unstreetable (wild bridgeport, PP, 12kRPM redlines).



-Ted

RICE RACING 08-07-01 08:05 AM

I have seen n/a PP 13B's make 380BHP@9500rpm...now what the hell that is in rwhp? depends on who's dyno and heaps of factors.

It would be no more than 320rwhp.

1/4 times would be in the 10's no problem in a car weighing around 2200lbs or 1000kg running 10" slicks on a drag track.

Expect mph to be in the 118 to 122 range with road car type gearbox etc.

It would be too extreme for the street, and when run in street trim (read: an exhaust muffler) would be down alot of power and revs.

go_speed_go 08-07-01 08:27 AM

A guy I know runs a shop with a dyno who tunes SCCA ITA cars. ITA cars must retain the stock porting, but intake, exhaust, ecu, pulleys, etc are allowed. He said that 220-225 at the flywheel was commonly attained. This isn't for the street since the exhaust system measures at about 104db at full throttle.

MAZMAN 08-07-01 08:51 AM

the guy was asking how much power without taking the motor apart...that puts him in the ,NO bridge or PP port motors.So i would agree with RETed about the "no more then 200hp"

mazdaspeed7 08-07-01 11:41 AM


Originally posted by rxspeed87
hey mazda speed when you get that mustang MAF let me know man
I going wanting get more power on my own N/A here
how much of a diff did the manifold port make on your car?
also what would you say for exhuast
N1 dual with header and downpipe. or the true dual like what mazda trix sells

Check this out for a little more info on the ported intake manifold.

My exhaust is true dual like the Mazdatrix one.

PaulC 08-07-01 11:46 AM

Its quite possible I belive to put 200+ hp to the ground since Chris and Rocky at Rotory Performance (www.rx7.com) said they can put one together with some very mild porting and bolt ons and keep it as streetable as a stocker. They also will garuntee the power since they have a dyno right there at thier shop.

:blue:

ItsRotary7 08-07-01 11:47 AM

Go speed is correct the max amount of horsepower you can expect at the flywheel on 2nd gen 13b is 220-225hp, which with a low figure of 18% drivetrain loss you end up with about 180hp.

There is also a guy who has just been working with a 2nd gen 13b streetport who has managed to get about 250hp at the flywheel, but that was using a motec fuel system.

The reality thing is that most people talk about how much horsepower they have, but most cases it is based on someone else measurements or what the ad in the mag said that they get by adding it to your car.

I will be within the next month giving figures of what parts do what to a 13b as I am having a Clayton Chassis Dyno installed.

PraxRX7 08-07-01 11:50 AM

The fastest N/A I have seen
 
My friend has an N/A that isn't really a looker, but it has a sweet engine in it.

It has upgraded rotors, flywheel, you name it. 1200cc injectors mmm

He is pulling off a nice 249 HP to the wheels right now, 40 HP more than my near stock Turbo II.


PraxRX7 08-07-01 11:52 AM

he also has the nasty big port though
 
He does however have the Big Bad Port that breaches the water seals...so his engine life is limited

ItsRotary7 08-07-01 12:36 PM

I like to see the dyno figures on the motor. What year motor is it. I didn't think you could put that large of a port on a 2nd gen motor with six ports without filling the ports and starting again.

What kind of computer is he running.

Ryde _Or_Die 08-07-01 06:42 PM

1/4 mi times?
 
I see that the basic figure everyone went with was around 200-230 Hp...what do you think that would add up to in 1/4 mi times with a good driver? And with slicks? Thanks again.


Chris

RETed 08-07-01 10:53 PM

Re: he also has the nasty big port though
 

Originally posted by PraxRX7
He does however have the Big Bad Port that breaches the water seals...so his engine life is limited
It's called a "J-Bridge", and it's just an extreme bridgeport.
This doesn't count, as this is NOT "stock ports".




-Ted

RETed 08-07-01 10:55 PM


Originally posted by PaulC
Its quite possible I belive to put 200+ hp to the ground since Chris and Rocky at Rotory Performance (www.rx7.com) said they can put one together with some very mild porting and bolt ons and keep it as streetable as a stocker. They also will garuntee the power since they have a dyno right there at thier shop.
Too much talk...I wanna see it built and proven, but I said STOCK PORTS, so no porting is allowed.




-Ted

mazdaspeed7 08-08-01 01:15 AM

Ted, I will get my car dynoed before I pull the engine and port it. I will have the graph online before and after my porting.

How much hp would it take a n/a FC to lose to a 300Z TT by only a car length and a half in the 1/4 mile? I raced one last weekend and that was the result. The 300 Z had intake, but was otherwise stock. I actually pulled ahead a little at the top of 1st, then he pulled to a car and a half in front of me in 2nd, and 3rd was dead even. We both shot down at 100 mph. It was on the street, but we raced at the place everybody goes to race, and a 1/4 mile is marked off.

Felix Wankel 08-08-01 02:07 AM


Originally posted by MAZMAN
the guy was asking how much power without taking the motor apart...that puts him in the ,NO bridge or PP port motors.So i would agree with RETed about the "no more then 200hp"

Me too.

RETed 08-09-01 01:29 AM


Originally posted by mazdaspeed7
How much hp would it take a n/a FC to lose to a 300Z TT by only a car length and a half in the 1/4 mile? I raced one last weekend and that was the result. The 300 Z had intake, but was otherwise stock. I actually pulled ahead a little at the top of 1st, then he pulled to a car and a half in front of me in 2nd, and 3rd was dead even. We both shot down at 100 mph. It was on the street, but we raced at the place everybody goes to race, and a 1/4 mile is marked off.
A Z32 turbo is one of the worst cars to race.&nbsp A stock one barely does mid to low 14's on the 1/4-mile track.&nbsp Due to the anti-squat geometry on the rear suspension, it is a VERY HARD car to launch correctly - how many really fast Z32's have you see at the drag strip?&nbsp Even a typically modded Z32 (intake, exhaust, more boost) barely cracks 13's in the 1/4-mile.

By your description, you car looks like it does the 1/4-mile at around mid to low 14's.&nbsp I know of another NA FC that cracked a 14.0x - that car ONLY dyno'd at 170hp to the rear wheels.

Eagerly awaiting dyno graphs.

Dudes, I know it looks like I'm ragging you, but my experience shows that your claims are not possible.&nbsp If you do prove me wrong, MORE POWER TO YOU!&nbsp I really want to see if it's possible to build a pretty quick (I'd be happy with mid 13's!) NA FC, as we're close to building a NA FC for NASA Pro Sedan class racing using a '89-'91 engine and ECU...






-Ted

mazdaspeed7 08-09-01 11:53 AM

Ted, heres what I think about all this. 230-240 bhp is possible in a stock port engine, but only in an ideal world, and it would need a Haltech or other ECU to do it. But we dont live in an ideal world, and things tend to not work as good as they could/should. I took my car to the track, but my intake temps were sky high, which was killing my power. it was also my first time at the track. My car felt very slow whewn I was there. I need to make a cold air box so I can get my temps down.

With my current setup inhaling hot air, I would be happy to hit 200bhp. with a cold air box, 210 could be possible.

Also, the stoxk MAF sensor is a major restriction on the intake side. if you can get rid of that with a Haltech, my previous numbers become a little more realistic.

Felix Wankel 08-09-01 12:02 PM

Big fat ass bridgeports with 51 IDAs are barely getting over 250-300, so I don't think 250 is possible on a stock port engine.

gr0undz3r0 08-09-01 01:09 PM

hp na stock
 
I am building my stock block 87 gxl na right now and when I start trying out stuff I will be posting the information later on my site. Eventually will port the block and do some other things but in the mean time goto groundzero.rx7life.com. It will be atleast a month before I am on the road though.

mazdaspeed7 08-09-01 02:49 PM


Originally posted by go_speed_go
A guy I know runs a shop with a dyno who tunes SCCA ITA cars. ITA cars must retain the stock porting, but intake, exhaust, ecu, pulleys, etc are allowed. He said that 220-225 at the flywheel was commonly attained. This isn't for the street since the exhaust system measures at about 104db at full throttle.
I exhaust isnt very legal, and it is very loud. Do you know if they were still using the stock MAf sensor on those engines?


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