so... HI GUYS

I have been on this forum before back when i had my gtu/t2 project car ( that sadly never got off the ground ), but i have found a GTUs that im ganna get at the end of the month.my plan is to make a another s5 t2 swap, seeing as its been a few years, i dont remember the specs like i use to. the build i wanna do ultimately ends with the thread title, the build includes

A. porting
Im trying to figure out which porting would more beneficial for the desired hp and ddness. obviously (look at the name) street port would be the best for dd, but i have heard that large street port robes you of lower end. to combat that i plan to use the stock turbo. its fast spooling its great for what i want the car to do, and with a lil porting might be able to squeeze 2 more psi out of it.

on the other hand the is the half bridge. i will be honest, dont know much about it. i do know or have been told rather, that it allows you to keep your bottom end power and increase mid-to-top end power. so please comment on this.

also want to port the exhaust. i was thinking race port since it is the biggest, but i dont know how loud that will make the car for street ability. so as well comment on this.

want to port the intake manifold as well, i mean hell, every lil bit helps.


B. fuel and PSI
so i have a chip left over from my previous build from a guy out of AU. pretty nice guy and pretty knowledgeable on tunning. talked with a few of his customers who actually got to use his eprom chips, and were very impressed. had no issues to the date i emailed them, asked people with different cars as well and they seemed to be pleased with his work. so i plan on using his chip in this build.
what it does is basically fuel cut delete, rev limit removed, maxs out stock injectors, i believe it decreases the 2nds to a lower rpm (i cant remember what rpm i'll have to look it back up), maxs the stock turbine out to 15psi.
now idk if i should go with his chip or, if i should get like a set of 1000cc 2nds and get another chip. gas mileage isint like a factor (lmao is ever with a rotary ?) my goal for that is i want one tank to last me a work week there and back and ill be happy. the driving will be all highway only and only a 18min drive.

now i want to try and keep the stock turbo and tmic. i believe im right saying the stock tmic maxs out at 12psi ? i plan to combat this with an ahcl injection kit, and just hope it will allow me 3 more psi lol. as stated before im going to port the stock turbine a bit and rebuild it.

C. exhaust
now of course turbo back 3in exhaust. i mean thats a given lol. i however have questions about the stock manifold. i know these bad boys throw out the heat, and that ebay manifolds aren't the best by any standards. i was thinking maybe ceramic coat it and then powder coat it to help against heat. then again i dont even know if it will work.
heres the link
http://cgi.ebay.com/ebaymotors/1989-...Q5fAccessories
now if it doesn't even allow the stock turbo to line back up in the original position screw it ill port the stock one. i just put that out incase anyone happend to have it. ill have to block off that waste gate opening.

D. deletes
probably going to delete power steering, and the fan (even tho it doesn't robe much) and replace the cooling system with an aluminum rad, and duel electric fans. of course all emissions will be gone as well.

so any way there you go. AND please lets just use constructive criticism as i said its been a while. i dont need any ones " haha newb has 3 post i have a bigillion" or " dumb newb you cant get that with those mods" ego trips in here.

thanks in advance.

 

to be honest, you don't even need porting for what you want. however, if you're hell-bent on it, then go with a streetport. forget the race porting on the exhaust, leave it all mild. i won't speak on turbo choice, but i think engine management will be a crucial decision for making reliable power.

 

well thats nice to know. only reason i wanted to port at was the fact that the engine is going to be broken down for rebuild any way so lol what the hell ya know get all you can squeeze.

 

any suggestion on what would be good fuel management ? i dont want to go stand alone im sure i can get an eprom to do what i want, and i know theres a good company out there that makes them..... but there name escapes me.

 

I'm pretty sure your talking about RTEK. They make great chips for FC's.

Like said before, your going to be able to easily make your target HP with a streetport on stock turbo. Most people running stock turbo and block get close to 300WHP before maxing out the turbo (with good tuning of course).

 

YES ! thats them, couldn't for the life of me think of their name. Thanks for that.

OK, this is good. i do have in my current possession a pineapple racing med street-port and tools for porting ( i half-@$$ tried to port my last turbo engine my self wasn't great but wasn't bad either).

so what about the stock tmic ? like i said i'll AHCL injection to combat heat sink on it but does it max out at 12psi , or am i mi-quoting ?

 

The stock turbo will make these power levels but be rather inefficient. Check out the mild stags of the BNR hybrids. 280HP will be easy.

Don't bother porting unless the engine is already pulled apart. And even then, for such a mild power level, don't go too wild. I'd probably just leave it stock.

As long as you don't push the stock turbo, then alcohol injection isn't necessary.

I think the best plan is a hybrid stock turbo, RTek, 720CC secondaries, upgraded fuel pump, exhaust, etc.

 

yeah i was just playing around on the rtek site and saw they now have the programmable s5 ecu. last time i was in a rotary they were just talking about maybe producing it. seems like a pretty good price to so that will more than likely be fuel management, i remember the s4 guys were in love with theirs when they came out. that a good enough review for me to get it lol.

who should i look to for hybrid stock turbo's ? or could i get the parts and rebuild them myself ?

yeah i remember that bnr was a great upgrade for these cars and pretty cheap to buy and rebuild. i know it would be the easier way to make the hp but, im pretty bent on using the stock turbine... thats why i was looking at porting the engine to try and get the extra horsepower with out killing the turbo. i am going to have the engine rebuilt so porting would be the bonus from that and dont really plan on porting the exhaust anymore based on reviews here maybe just polish and debure the outlets.

now this is a newb question, but i just cant remember, the stock s5 injectors are 550 hi imp both 1st and 2nds right ?

 

what fuel pump should i upgrade to ?

 

dude: Microtech, 750's, Fmic, Bnr stage 3, koyo and that would be an awesome car to drive


The microtech is for when u go bigger.... because u will

 

to comment on ur porting i hear bridge porting even a half bridge makes the turbo spool faster and maintain the max boost longer. i remember reading someone saying that the max boost stock was at like 6k and ended at 6.5 and after a half bridge it started at 4.3k and went to like 9k. but idk how true that is.

 

dang, if thats true.. thats a pretty significant diff.

 

Yeah no $#!+ lol

 

I agree you don't need any porting, but since you are pulling the motor apart why not! Like said above you will most likely want more out of the car down the road so go ahead & do the BNR with some porting to give you a little more room to play with in the future. Good luck with the build & happy to hear you are back in a Rotary!

 

im liking this thread cuz i was thinking the same hp as dd that the op chose. now all my answers will be solved.

 

i read it in the half bridge vrs full bridge thread thats super long but has alot of good infromation. read the stuff from people that know what their talking about aka bdc and aaron

 

thanks rotordad of course you always want more lol. thats my plan to when i do upgrade from the stock turbine to a bnr or holeset.

 

ding ding ding

listen to the voice of experience. I agree with everything in Aaron's post. I think the OP has fallen into a trap many fall into... "I'm going to start with this turbo, and then I'm going to do every mod I can to incrementally get me that extra hp I want without having to upgrade the turbo." Just let the turbo make the power. You'll end up with a less complicated setup that way, especially with this modest goal.

 

well after review and talking to you guys heres my plan.

med street port, I know just upgrading the turbine is the best and easiest, but for the time being im just ganna use stock and street port.

upgrade to the 2nds to 770.

rtek stage 2 ecu

and then the bolt ons, deletes, and emission removal.

i mean i really will be happy with 280 dd whp and if hte stock turbo can put people passed 300 then i shouldn't be pushing the turbo to its max limits. the street port is really for a future plan, i know you said im ganna do everything i can without upgrading the turbine, but, i mean i might aswell do it while its broken down. other wise it will be point less in the future.

 

you're in for some disappointment with the stock turbo. you are going by estimates from optimistic people on the internet reading generous dynos. it won't meet your goals, you won't be happy with it. a street port on stock turbo doesn't even help that much, the stock turbo can't make much power over 5500-6000rpm which is where the porting helps the most anyway.

keep the motor you have (stock ports) and put a bigger turbo on it. with a street port and stock turbo, the ports easily outflow the turbo.

 

now see that i did NOT know, and i just saw durtled post as well about no power over 6.5. ill look into some bnr/ stock hybrids like you and aaron have been talking about. my main reason i wanted to keep the stock turbine was its fast spooling time and i heard it was good to about 14psi. however i didnt know, like you said, it stopped making power at 6k.

 

The BNR hybrids do use the stock turbine in the early stages. All you need is a stage 1 where they just clip the turbine. I doubt you'd notice any real lag.

The stock turbo will give you 250-275HP, after that it is just blowing hot air. Especially with a top mount, it won't do you any good.

Ignore all the crazyness with bridgeporting. Bridgeports are not for stock turbos.

 

yeah ive been doing alot of homework past few days, if i port it will be street only, and i doubt ill even do a large port just a small to med.

 

I have a half-bridge and its not bad at all to drive on the street, but for a stock turbo its crazy overkill. i saw ur plan and if u go with a Bnr i think ur gonna have a blast with that thing.

O theres a guy selling an Lt8 for $450, snag that thing up lol

 

lol nice