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-   -   240rwhp N/a!!!!!!!!!! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/240rwhp-n-36628/)

kim307 12-04-01 01:21 AM

240rwhp N/a!!!!!!!!!!
 
What would it take to make a N/A put out that kind of number? Is it possible? I'm talking about all-motor here. No turbo kits, superchrager, or NOS.

Jay Kim

tweaked 12-04-01 01:34 AM

series 4 or 5?

supergoat 12-04-01 01:40 AM

Port the shit out of it.

Mallard Duck 12-04-01 01:48 AM

I imagine you could, with ports the size of watermelons. You'd get that sort of output at some sort of stratospheric RPM, but have little low-end power.

tweaked 12-04-01 02:04 AM

I saw some thing on th enet about a guy that took an 86 modded the shit out of the car and still wasn't happy. so he took fiberglass and made an intake manifold for a 2 barrel carb, Weber I think. Any way he made it so the carb only worked after 3000 rpm. he used the carb with the stock fuel injection. cut holes in the rotor hosing it looked like. the fuel injecton system looked nomal. crazy shit. I think he was in the prossess of fine tuning it. I am going to try to find that site now

HWO 12-04-01 02:29 AM

Re: 240rwhp N/a!!!!!!!!!!
 

Originally posted by kim307
What would it take to make a N/A put out that kind of number? Is it possible? I'm talking about all-motor here. No turbo kits, superchrager, or NOS.

Jay Kim

at least a 13B Bridge Port with a 48mm IDA or Side draft feeding it.

A Bridge port, J Port, Monster Port or Peripheral Port either Carburated or Fuel Injected will make 230rwhp or more.

baix2 12-04-01 05:22 AM

i am sure it's possible but cost a lot..

if i were you then i would just built a turbo model and can acheive that hp with much less money...(unless u are obsess with NA)

FPrep2ndGenRX7 12-04-01 07:00 AM

There are a few people on the forum that claim when they are through with their mods they should have around 230-240 HP on a stock port motor. All I can say is produce a dyno sheet as there are many on the forum interested in the results.

Back to the question originally asked, port the hell out of it and buy 10,000 RPM tach since the factory one only reads to 7000 or 8000 depending on the year of the N/A its in.:)

jimmyv13 12-04-01 07:43 AM

Re: Re: 240rwhp N/a!!!!!!!!!!
 

Originally posted by HWO


A Bridge port, J Port, Monster Port or Peripheral Port


What's a J Port? Are monster Ports and Peripheral Ports the same?

EProdRx7 12-04-01 07:56 AM

My motor,
1 - port matched TB with "choke" butterflies removed.
2 - 89 intake port matched lower manifold ported and matched to block. Sixth port actuators removed and filled.
3 - Street port (Mazdatrix templates).
4 - 90 rotors stock
5 - 85 GSLSE E-shaft
6 - Exhaust ports by Rodger Mandiville
7 - Fully ballanced rotating assembly
8 - 5.5 clutch and 3.5# flywheel
9 - Mazda comp header, custom exhaust
10 - Stock FI 86-88 with modified ECU, stock sived injectors
11 - Cosmo fuel pump
12 - NGK race plugs with stock ingnition
13 - underdrive pullies
9300 rpm =199.7 hp at the rear wheels, est. 240 at the flywheel. I have the dyno sheet to prove it.

jimmyv13 12-04-01 09:09 AM


Originally posted by EProdRx7
My motor,
1 - port matched TB with "choke" butterflies removed.
2 - 89 intake port matched lower manifold ported and matched to block. Sixth port actuators removed and filled.
3 - Street port (Mazdatrix templates).
4 - 90 rotors stock
5 - 85 GSLSE E-shaft
6 - Exhaust ports by Rodger Mandiville
7 - Fully ballanced rotating assembly
8 - 5.5 clutch and 3.5# flywheel
9 - Mazda comp header, custom exhaust
10 - Stock FI 86-88 with modified ECU, stock sived injectors
11 - Cosmo fuel pump
12 - NGK race plugs with stock ingnition
13 - underdrive pullies
9300 rpm =199.7 hp at the rear wheels, est. 240 at the flywheel. I have the dyno sheet to prove it.

Post the sheet. What car is this in?

pp13bnos 12-04-01 09:25 AM

My old peripheral engine put down 245 or 240rwhp, without nos, turbos' etc. However, i was running the injector duty cycle up around 130%, at 65psi of fuel. Can you say the injectors where a little to small? I do have a dyno sheet, but no scanner:(

CJ

EProdRx7 12-04-01 09:29 AM

the car is a SCCA E production race car. see it at:

http://www.scca.org/amateur/club_rac...photos/EP6.jpg

I have to scan the sheet. I'll see if the dyno guy has it on record. BTW this motor is for sale. As is the rest of the car. Make me an offer

tesla042 12-04-01 09:43 AM


Originally posted by EProdRx7

8 - 5.5 clutch and 3.5# flywheel

Geeeeeezus! Isn't the stock one like 29 pounds? Where did you get a 3.5 pound one? Is it even driveable?


and pp13bnos... what do you mean, 130% injector duty cycle? are you factoring in the added fuel pressure in that number?

-Tesla

EProdRx7 12-04-01 09:53 AM

The clutch is made by Quartermaster and sold by Mazda Comp. No it is not drivable. It is in or out, nothing between. :D With hot slicks it makes for some interesting maneurvering in the pits...

http://www.mazdamotorsports.com/weba...ngId=-1&id=952

No pic of the flywheel, sorry. Whole deal goes for about $1200

tims 12-04-01 10:17 AM

I have seen two N/A 13b's that can make this type of power, with dyno records to prove it. First was a 13b peripheral port with a 51mm Weber IDA, made 240hp at the wheels at about 8700rpm. Second was a full Motec injected street ported 6 port 13b E production motor that made 218 hp at the wheels but would only last two or three laps before it blew up. this motor had ceramic apex seals and hours of dyno time to develope. they built three motors just to test the porting and exhaust. the peripheral ported motor is the only easy way to get to those numbers. We are in the process of testing and dyno tuning a 13b fuel injected peripheral port motor. we are hoping to make 250-275 hp at the wheels. Dyno work is scheduled for the weekend before christmas so I will post the results when I have them.

EProdRx7,
that is a very nice car and I like the body kit(did you build it yourself or buy it?). my turbo should end up looking exactly like an E production car. Maybe I'll built a N/A motor and try some SCCA races sometime soon. what size and type tires are you running? thanks

EProdRx7 12-04-01 10:23 AM

I know the motors you're talking about, too bad they popped.

ItsRotary7 12-04-01 10:28 AM

Well first off EProd we make the sort of power with our ITS cars, with and 89 motor, no porting, open exhaust, full fuctional six ports and VDI.

I also know of a very large street ported motor running a motec fuel injection system that has recorded over 230 rwhp, we hope to copy there designed in the new Ep car we are building.

By the way why are you selling yours.

EProdRx7 12-04-01 10:54 AM

Well I raced in ITS also and won a lot of races. Sylvan (you know who he is) claims the most he has ever gotten out of an ITS motor is 165 at the wheels. Haskel (works for ST) says he can get 175. I think they are both trying to sell motors. If you are getting 200 from a LEGAL its motor I will buy it from you. name your price. But if it is an ilegal motor I want double back!
I am selling my car because there are people in this form of racing that are willing to spend $30k for a motech system and $120K on the rest of the car. Someday they wil learn how to drive and I wont have a chance. I just don't have the desire to win a club race that badly.

supergoat 12-04-01 11:00 AM

So exactly how much torque are the high HP N/As putting down?

Gene 12-04-01 11:19 AM

In one of my japanese rx7 magazines there are pictures of a "sequential port" motor with custom intake manifold. Basically it works like 6 port, but instead of normal 6 port, it opens up a peripheral port at high rpm

ItsRotary7 12-04-01 11:36 AM

Hey E-Prod, I can tell you from fact that Syl and Haskel are getting well over those amounts from there motors. One of the guys down here bought one from them and it made well over 175 hp.

We made more horsepower by setting up the exhaust for the motor. By changing the characteristics of the exhaust on a dyno we managed to get 14 more rwhp than we had using a RB or Mazdatrix exhaust setup. Most of these units are designed to be generic use, but have not been designed to pull the max amount of horsepower out of a motor. So there is no need to buy a motor from me, get your motor tuned on a dyno. It might take a couple of tries, but every motor is different. We switched exhaust from one car to the next and it made less horsepower but more torque through the RPM range.

Now with the new rules coming out for IT allowing the use of computer upgrades, it will mean having to spend a whole lot more money and time on R/D to get more out of these motors.

FPrep2ndGenRX7 12-04-01 12:43 PM

Hey ItsRotary7 - Any secrets you want to share on the exhaust configuration? Some of us can't afford multiple dyno runs and would like to know a good starting point for our tuning. I'm running in FPrep SoloII and any extra torque is always nice expecially midrange. Currently its your standard Racing Beat Header that collects about 48" donwstream and then exits out a single SupertrappMuffler with no disc installed. Does this sound like I'm on the right track?

Thanks

ItsRotary7 12-04-01 03:47 PM

Well Fprep your on the right track, we use a tuned header from AWR into a single 4" pipe a couple of 65 degree bends placed about 12" after the end of the header straight back into a single dynomax muffler, I also have tuned with a super trap, but you need to dyno it and change in discs to see what works for your car.

It might not increase horsepower but if you look at the amount of time your motor is above the specified horsepower, you need to adjust so your motor doesn't just peak. If you can set up your motor so you make x amount of horsepower for the max amount of time. Most engines will start to make horsepower then peak, if you can get that horsepower to stay on for more rpm.

Mazdarules 12-04-01 05:55 PM

Wait a year and buy a Renesis block :)


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