c'mon tims it's friday, I'm waiting for these astounding numbers

 

I knew you guys would be waiting to pounce. the dyno day was a success. the engine runs great and it is running slightly rich for some personal comfort. One thing the dyno proved is that the throttle body and intake are a sizable restriction. the engine was still in a vaccum at 8000 rpm. Best max HP I could get was 190HP to the rear wheels at about 7500rpm. final setup is 180HP at about the same rpm. Not what I was hoping for but the engine runs clean and smooth. Starts and idles well also. I had never promised any wild numbers for my engine. I was reporting stories and tall tales I had heard(these now sound like out right lies). It looks like the EP regulars know their stuff. My engine would be absolutely legal for EP and with some legal work to the throttle body you could get a little more air and HP. But I don't think you could get another 50-80HP without some serious modifications to the intake and TB that would likely not be legal. I will post the complete dyno sheet tommorrow(I forgot it in the truck). Man what a long day/night.

 

they don't call us the forum "smart" asses for nothing not bad numbers at all though. We are hoping to get around that same number, if so we'll be in good shape. Just for fun when we get on the dyno we'll post the slip too. What dyno was it on do you know? we'll be on a AWD mustang dyno, which supposedly likes to read less optimistic than others. Either way 180-190 is good on an NA congrats man.

Ron

 

Agreed. Good job Tim. I'll post up my details as well. I'm buying an EP motor from Tom Thrash with his port. I'm tearing down my other motor to see why I blew a rear rotor apex seal (again). I'm still a month out, but I'll post up when available.

Paul

 

The Dyno was a Supeflow, not sure which model. It had a few options that previous dynos I have used did not have that made tuning much easier. The guys at Westech Performance (http://www.westechperformance.com/) did a great job. Tom was by far and away the best dyno operator/tuner I have used. He did all the work. All I did was "drive" the car on the dyno and follow his orders. Specs for my engine are OEM intake and throttle body from a '91 RX7, turboII injectors, variable intake "drum" removed, AWR header(longer than would be optimal), straight through exhaust, home made "cold air" intake and K&N type cone filter, and all controlled by a Haltech E6K.

 

Image of HP curve. sorry for poor quality scan.

 

Tims, What did you replace VDI Drum with.

 

Nice powerband!

 

I just removed the drum all together and plated off the large hole. I did some experimentation early on and could not tell a difference(not on the dyno), so I just removed it. I seems to run great and the powerband is nice and flat.

 

Actually, it hurts horsepower. The Air as it comes down the tubes hits the large chamber and creates a masive amount of turbulance. The air does not no which why to go. You should fine and inmrpovement in horsepower and torque if you put it back in and Wire the VDI open.

Your horsepower figures are still two low for and Basic EP motor with EFI. You should be about 200hp at the rear wheels, without having the intake manifold modified

 

which passages are considered the "open" position.

 

The Plastic valves holes should line up with the cross holes in the intake manifold. What that does is shortens runners in the intake manifold which gives you more horsepower in the upper rpm but less torque.

If you had left the valve in their then closed it so the holes in the intake manifold where closed it would make the runners longer which would give you more torque in the lower rpm and less hp.

You should find that you were down about 15 to 20 hp on your dyno test.

 

As I recall (been a while since I looked at it) there are two seperate passages and depending on how the drum is turned one or the other passages are open to the main "plenum". so which section should be open to the main? I don't know how the stock setup works. I have never seen any of this stuff operate on a regular road car, so I don't understand which section should be open/closed. I have raced this car for a while but I have never even driven or worked on a stock RX7 of any kind.

 

Actually Tim, both passages are open at the same time, when the valve is turned the correct way. The passages are straight across from each other. You trun the valve so it connects the passages on one side of the tube to the other. I would be interested in what you find on the horsepower when you re dyno it with this changed. I have been looking into changing my ITS car into and RS car which I can install a Haltech System. I am real interested in what you can get out of it.

 

I have to look at that drum again. I remember looking at it and trying to visually see which direction would be best. I ran the engine without the current tuning and saw no change in either orientation. I ask around a bit and I had heard of people just removing it, so this is how I started. I'll look at it this weekend and see if I can figure it out.

 

I finally got to the shop to look at the intake drum. I set it to have the holes in the drum running paralle to the ground connecting to two runners side to side. I'll see if it makes any changes this weekend.