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-   -   My first ported motor build dyno #s (https://www.rx7club.com/time-slips-dyno-128/my-first-ported-motor-build-dyno-s-777685/)

dpf22 08-07-08 02:51 PM

My first ported motor build dyno #s
 
2 Attachment(s)
Ok people, I am a lurker... Don't post much, just read info and such. I had built a motor over ther last winter because I blew the last one up (go figure).
Here is the rundown of what is done to the car as far as power and motor are concerned.

The motor is based on s5TII irons that are a modified pineapple med streetport template. That means I cut the initial port, then modified from there based on a few ideas of laminar flow of air and such. I am no engineer, just guessed and made them as even as I could. First time porting btw.
The Rotor housings are S6 with less than 5k miles on them. (lucky find, almost new) The rotors are s4TII; Lightened and balanced with s5 counterweights by Carlos Lopez of CLR Motorsports (great guy btw).
Stock s5 eccentric shaft from the old motor. New s5 stat gears (wish I had the money for fd ones)
New oil pump with modified galleries and blocked off front cover oil outlet. Uber oil pressure.
I ported the intake manifold and relieved some flow restrictions in the lower section. I also ported the throttle body and added an actuator to the 3rd set of throttle plates to open at a specified pressure.
As far as the outside of the motor, it has a stock s5 turbo that has probably got about 50k miles on it. 2.5" downpipe and 2.25" cat delete pipe to the stock "Y" pipe and mufflers.
The intake consists of a generic intake to the turbo. 2.25" to the ebay intercooler(24"X10"X2.25" core) 2.5"-2.75" to the greddy compression elbow into the motor.
Fuel system
Denso supra pump
aeromotive fpr
720prim
1680sec
rails ran parallel

Megasquirt ems.
And thats about it for the engine.
The dyno was a dynamite uncorrected for altitude (~4500ft)
Here they are :) One at 9psi and the other at 12

junito1 08-07-08 04:54 PM

Congrats man!~

I will be attempting to rebuild my old and tired s4 tII. Im tired of havi8ng to deflood it on hot starts.

gxl90rx7 08-07-08 05:44 PM

nice.. some people still call BS at 250whp on stock turbo, and youre almost breaking 260

dpf22 08-07-08 07:24 PM

^^^
this is very true. I could have turned the boost up, but I didn't really care to.
honestly there are a lot of people who don't like megasquirt either. Its just been a really strong motor this whole time. Fun as hell to drive. Heh, its faster than a lightly modded c5 zo6 Vette (intake and exhaust combo/ free mods).

I have no fear that I can eclipse the 260 mark with more boost. Especially since I just barely replaced the restrictive stock exhaust and midpipe combo that I had. MAJOR difference, but I haven't dyno'd it since it was only day before yesterday.
There are a lot of little things with this motor that I have done that I have not mentioned simply because it could take a while to explain.
I would like to think that the extra power comes from taking time to smooth transitions and eliminate restriction in the lower intake manifold. I port-matched EVERYTHING haha. I even made the greddy compression tube match the walls of the throttle body on the inside. (The casting sucks on those things, I wouldn't buy one again)

The devil is in the details and it shows. I didn't have an insane budget, I just made sure everything that I had was as good as I could make it. Ah the wonders of a dremel tool lol


dpf22

2-N-D-pink 08-07-08 07:49 PM

good job!

dpf22 08-12-08 07:50 PM

Thanks :)

Alex Rodriguez 08-12-08 07:59 PM

not bad personally anything over 250 whp on the streets no matter if you got drag radials you will not hook

i say good job bro , 258 whp and running the stock hitachi ,shiiiiet thats boost as soon as you step on the throtthle

right now i am at 10psi and pushing 365 whp , i dont hook for nothing but hey the power is there if i ever need it

blackedoutFC3S 08-12-08 09:32 PM

nice build dude! sounds like a great job well done

dpf22 08-14-08 02:41 PM

Thanks everyone for the positive feedback. I was honestly expecting a lot of people to call bs on me because of the numbers and how rare it is to see them that high with the stock hitachi piece. I am very happy with the motor as is. I can't wait to get a larger turbo and start working towards my goal of 400whp. I already have the fuel system for it, just tuning, which I do all of myself

sharingan 19 08-15-08 11:10 AM

260 is doable.

I had a buddy who made damn near 300 on the stock hitachi w/ a mircotech and full RB exhaust.......2 weeks later he was looking for a new turbo :lol:

thatguy23 08-18-08 10:24 PM

bump

Omixeo 08-30-08 11:55 PM

So from the two different runs, the first one being at 9psi and the second one being at 12psi, you made an extra 8whp from an additional 4lbs of boost? Maybe im reading something wrong here because that doesn't make sense.

RotaryRocket88 08-31-08 02:19 AM

The stock hotside tends of choke the engine at high pressure/load, which is why the power starts to drop off towards redline. This is especially true if the exhaust system is restrictive, which his apparently is with the 2.25" pipe and stock y-pipe/mufflers. The additional 3psi did give a significant increase in torque between 3700 and 4500 RPM though. There's a 20+ rwtq gain there.

dpf22 08-31-08 02:20 AM

it actually makes perfect sense. The turbo is entirely too small and I am pushing it further than its supposed to be pushed. Notice the almost 30ft/lb gain???

When you are on the outer limits of a compressor's flow capability, you don't gain much by adding boost. Oh, and its only 3 psi difference, I don' t know where you went to school but 12-9=3.

arghx 09-01-08 11:12 PM

hopefully you're going to put a real turbo in there...

dpf22 09-12-08 12:56 PM

I had planned on it :)
I just need to finish a few things with suspension and body work before the turbo system gets rebuilt.

SupSai7 09-14-08 01:18 PM

Badass! Good work on the car, have any pic's?

dpf22 09-14-08 03:20 PM

1 Attachment(s)
lol, my avatar mabe. My car is a little bit ugly. I resized one with my friend's rpf1's on my car. I actually have FD wheels normally.

SupSai7 09-16-08 02:33 PM


Originally Posted by dpf22 (Post 8553081)
lol, my avatar mabe. My car is a little bit ugly. I resized one with my friend's rpf1's on my car. I actually have FD wheels normally.

Ahh good choice in wheels I hope to have a set on my car soon.


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