I have to decide if porting is worth the extra costs. Everyone has their own cost benefit analysis they have to do to justify the extra cost of porting. I have my own criteria. What I need to know are what are the real world performances increases with porting. In other words what is the real percentage gains over stock Mazda reman. I'd like to hear from the experts that have real world results. Lets say between somewhat moderate street porting and fairly extreme street porting.

Here is an example from Hayes web site:

Rotary Engine Porting Modifications

Increase horsepower with internal engine porting and
polishing modifications. Engine porting increases
capable fuel induction and reduces internal restriction.
All porting includes enlargement and polishing of the
intake ports. Fuel entry into the combustion chamber
is smoother and fuel CFM is higher.
Exhaust ports are also enlarged allowing for a quicker
and less restrictive release from the engine exhaust.
Expected CFM outputs are based upon calibrated liquid
flow bench measurement.
Most accessory upgrades will compliment any porting style.
Low rpm torque is reduced slightly, but the idle remains smooth.
All street porting styles can be utilized with stock accessories.

Stage I Street Port (10-15%) HRE-010
Stage II Street Port (15-20%) HRE-020
Stage III Race Port (20-40%) HRE-030

Note their claims of 10-15%, 15-20% and 20-40%.

I certainly don't believe 40% increase, nor do I know what to believe.

That's why I'm asking you guys, the ones that have real world results.

Now don't worry I'm not getting a Hayes motor. As many of you already know I went that route 4-5 years ago and took my lumps which ended up costing me $1,000s and I was without my RX-7 for 20 months.

I plan on making this decision in the next few days.

Thanx for your input.

Ken

 

those percent increases seem accurate but they are talking max power, high end torque.


first you should explain why you want to port your engine.

 

To get max power in streetable form.

My ported motor blew up and I want to know if it's worth paying lots extra to port a new one again.

Ken

 

potatochobit, where in austin are you located, i am curious if i have seen your fd around?

Thomas

 

On a fully modded car, Steve Kan stated that you would see about 25-30 rwhp with a street-ported motor, IIRC. I would think that for any situation other than one where the car really will remain close to stock, that a streetport would be worth the $300-500 it usually costs.

 

Mine is fully modified with a T66 and all the other stuff needed.
What kind of porting is going to give me this 25-30rwhp(moderate or extreme street porting?

Ken

 

Are the side plates on the blown motor fucked? Why by new plates? Lap and rebuild.

 

Motor is trashed according to builder. I really would like to see some real world numbers not guesses. Like here is my config with a strong stock motor and here it is after rebuilding with whatever porting.

I can guess too. I don't believe extreme street porting is going to gain 40%.

If it only gains me 10% it is not worth it to me. I can buy a Mazda reman 2mm seals for $2400 and a 12 month warranty. I can get a stage 3 street port, 3mm seals with 12 month warranty for $4k+.

I need real world examples.

You can see my signature, just swap the T04e for a T66.

Ken

 

No numbers of stock motor but I will have Dyno Number for my car on sat. Steve Kan is tuning mine saturday.

t51r

monster ito ports

VP c16

 

Be sure and get a b4 and after tuning dyno chart.

That's always nice to see.

Ken

 

my car is the one missing the headlight covers and has dents in both rear fenders. :/ it has the black rpm2 wheels
i moved to cedarpark/leander area recently but im usually in the parmer area

and of course extreme porting doesnt magically give u 40% power increase. you would be looking more at a drag car that cant go through the mcdonalds drive thru with those numbers. i dont quite follow your logic though... u had a KDR street port but ur asking how much of a power increase does a port give.... perhaps u bought the car with a built engine already in it?

when i had the new engine put in i decided not to port it. the reason being, my max HP goal would never be above 350HP. the stock engine and turbos can do that nicely. from looking at your current mods, its appears u will not be satisfied with a stock engine unless money is a concern at the moment. and i know this post is useless and i didnt give u any numbers, but thats o-k since i had to reply anyway.

 

Well, it's not tuned at all now. New motor, different port. Starting all over again. I did trap 122 before but my vehicle weight is pretty low.

 

stick with the street port 15-20 %, its worth it as both power and relaibilty for ur setup. but if u can get 3mm seals too, do it all in 1 shot,btter this way...main thing is never run lean...1 time, and the seals are gone, but with 3mm seals u mite get away a few times

 

I still need real world examples.

I'm sure my T66 with race gas and expert tuning with a stock reman and 23psi boost will get me at the minimum 400rwhp probably more.

Are you saying with stage III street port I'll get 460-480rwhp?

Here again I'm not interested in guesses.

Thanx,

Ken

 

Ken I think you are asking for data nobody here has.

I have a street ported motor that puts out around 345 RWH on stock sequential turbo, the PFS bolt-ons, & ECU and a high flow cat. With a midpipe I would expect another 15 HP. Nothing fancy and I ran 11.69. Totally drivable street car.

I know Rikki got 375 RWH on a Mazda reman, street port, non-sequential & midpipe set up.

Call Ray Wilson at PFS in Frederick Maryland He has dynoed a couple of hundred rotaries. He could give you an informed answer, as well as a properly built engine.

301-874-0611

 

there's a chart somewhere with tons of dynos of different setups. search and find it, then just choose the ones you'd like to compare and graph them

 

found it

http://www.catenet.net/dyno.php