Powerpack

First of all, as a moderator you're a good one. :newlaugh: :newlaugh: :newlaugh:

Secondly, I've never said that I'll be spending $800 just for porting. I would do it if I had to rebuild the engine for any reason.

And thirdly, it's not $800, it's $350 for a 6-port and $280 for the 6 intakes only. :madgo:

Powerpack

with porting like that about 200hp. gsl-se secondaries are recommended 680cc[/quote]

You're talking about a NA here, but with some upgrades in the exhaust system at least, right?



Thanks a lot Vosko.



Hopefully, not everyboby laugh at guys who wants to learn, I bet he doesn't know everything.

dac

You can probably get close to 10 HP by changing your air cleaner. A few more by adding a header and free flowing exhaust.



I wouldn't recommend a BridgePorted engine for the street. I had one years back in a R100 that I drove on the street and it.... Well sure it was fast (13 sec 1/4 miler), but it was like a really radical cam. No idle, very lopy at best. Botton end was pretty shallow, it was rev monster. It was fun at first, but got old quick.



I don't know of anyone doing bridgeports on 6 port motors. So to truly get a Bridgeport you would need to replace the housings.

vosko

with porting like that about 200hp. gsl-se secondaries are recommended 680cc[/quote]

You're talking about a NA here, but with some upgrades in the exhaust system at least, right?

Thanks a lot Vosko.



Hopefully, not everyboby laugh at guys who wants to learn, I bet he doesn't know everything.[/quote]

to take advantage of that porting you would need rb headers,presilencer, and catback, intake, etc. the car that has THAT engine is about as fast as a stock TII. you can make power N/A just not as much.

Powerpack

I just want do some changes here and there as you say, not big things but good things. The free flowing exhaust, is it just like a exhaust porting or is it a polishing? My idea is a street porting when I'll have to tear it down and maybe an RB exhaust system in near future.



When you only change the secondaries for 680cc, the stock ECU switchover correction factor will not match anymore (0.4 instead of 0.5), does this have some importance?



Thanks to both of you. :sigh:

1Revvin7

You would want to get atleast a piggy back fuel computer, i bet those injectors would make u run rich real quick and most likely stumble when they came on. U probably could even keep the stock injectors, just either bump up the fuel pressure or get a performace fuel pump. I know ur not supposed to run the injectors past an 85% duty cycly but the n/a injectors can handle 200hp. U could also get some TII injectors, which would still probably be an overkill, unless u did some HUGE porting. But if u did get TII injectors u would have to change the impedance, u could wire in a 10 omh resistor, to change the pulse length. Whats the impedance on the 680ccs? Whats ur question on free flowing exhaust? All they mean is open it up so there are no restrictions ( no restrictions as soon as it leaves the engine). If u can't push the air out, there is no point of trying to cram more air in.

Powerpack

I'm a technician in automated control system and electrician, and I can tell you that adding a resistor will not change the pulse length in any manner (it's the ECU's task). At most, it will help to keep the waveform more square but slower response. The resistor is for impedance adaptation with the ECU and to limit the current through the injector and ECU when the impedance is too low for operating directly on 12 volts (it would burn itself up). I already have low impedance injectors anyway. I would say that changing my low impedance for high impedance and removing the resistor pack could help. In my opinion, they should have a better response above 50% duty since it'd have the same current but all the voltage is going to the injector (12 watts instead of 2 watts with low impedance).



As for free flowing, I know it's not really as free as you say but I've been thinking about the cat replacement pipe w/presilencer system and the Cat Back system w/mufflers. I've thought about headers but it would probably be too loud. Is this a good choice? They say we can get about 13% of power increase from a RX7-146hp.



Thanks, sorry for being so harsh with you but you asked for it!

isamu

I thank everyone for their replies on this, it has been very informing.

Powerpack: the cars an 88.

Powerpack

Is the '88 and later model supposed to have more power, like 10 hp. Or were you talking about my 146hp car?

Hey...what about your rear rotor, have you checked to see if everything was in there? Is the apex missing? ???

1Revvin7

I'm a technician in automated control system and electrician, and I can tell you that adding a resistor will not change the pulse length in any manner (it's the ECU's task). At most, it will help to keep the waveform more square but slower response. The resistor is for impedance adaptation with the ECU and to limit the current through the injector and ECU when the impedance is too low for operating directly on 12 volts (it would burn itself up). I already have low impedance injectors anyway. I would say that changing my low impedance for high impedance and removing the resistor pack could help. In my opinion, they should have a better response above 50% duty since it'd have the same current but all the voltage is going to the injector (12 watts instead of 2 watts with low impedance).



As for free flowing, I know it's not really as free as you say but I've been thinking about the cat replacement pipe w/presilencer system and the Cat Back system w/mufflers. I've thought about headers but it would probably be too loud. Is this a good choice? They say we can get about 13% of power increase from a RX7-146hp.



Thanks, sorry for being so harsh with you but you asked for it![/quote]

damn u showed me up there :sigh: I have that same setup as ur talking about. I have Rotary Perforance's midpipe and some high flow mufflers. I would have got the header/presilencer combo but it was $250 more, and since i can't tune my fuel, i didn't want to mess around with a header. I think u will like it, its a good setup. ps yes i did ask for no hard feelings