s5 6 port turbo.. who's done it? questions inside
 

Hello to all that are reading this. I'm looking for some info on doing a s5 6 port turbo. I have a '89 GTUs, engine runs strong, rebuilt about 40,xxx ago. I've read alot of threads on s4 6 port turbos, but they do not have all the info i seek. Now it seems like the only way to get the proper info is if people who've actually turbo'd their n/a s5's chime in. Now for what i plan on running, I already have a microtech LT-10's, and plan on using s5 turbo upper and lower intake manifolds, s5 exhaust manifold and turbo, s5 front cover and baffle plate, and a walbro 255 fuel pump. First question is how reliable can i expect my car to be? What kind of boost can i run reliably, what injectors should i run, and is there anything else that i should consider buying for the build. Thanks in advance,

Izzy

you kinda need to give more info, whats your hp goals? and the injectors kinda depend on the boost your running and your horse power goals.... ive heard that people have run upwards of 15lbs on 6 ports, they have been reliable but they tuned there cars really good and had a really good fuel system.

Well i know you can push more boost on a s4 n/a engine due to the lower comp ratio as compared to the s5 n/a. as for hp goals i think that i'd be happy with 300 whp. I was hoping that i could run 10 lbs of boost, i think that i'd feel confident running that. so then i guess i need to know if that is really possible to do and have my car be reliable.

timing map
timing map
timing map

ironically i plan on running a similar setup sith an s5 na. just not the 6 port, i am using s5 tii LMI and UMI. from what i have been told from other members/and researched, for 10psi and 300 hp you ill wana run 720cc secondaries and 550cc primarys.. thats what i plan on running. i would be content with running lower horse power than you around high 200's. so maybe you will wana run a little larger injectors..im sure someone will chime in. and yes just like timebomb said, timing!!!!!!!!!!!!!! and you should be good

Since you have a microtech, I'd suggest stock 550's/680's for injectors since your sticking with the stock turbo.

As said before, tuning is the key. A conservative timing map and a little on the rich side for the fuel and you should be ok.

Your also going to need a oil filter pedestal for the feed line for the turbo. The return will be on the turbo front cover. I'd also suggest changing over to the T2 oil pump.

people actually read my replies?

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i just make shit up as i go along. :)

By chance do you know who or where i could get a good timming map from to start off with?

Alright, as for injectors i'll do a little more research on both setups suggested, and i will get a oil filter pedestal.

I will also search for a s5 TII OMP, but is this completely nessesary? I've seen this done on the s4 6 port turbos and they retain the n/a OMP. Just curious, and if i will infact be better off using a s5 TII OMP, I'll get one.

Wait.... you're planning on running the stock s5 turbo and hoping 10psi will get you 300hp?
You may want to reevaluate this idea. IIRC getting 300hp with the stocker at any psi is damn near impossible. You'll want to consider a bigger turbo, a BNR hybrid comes to mind as the easiest and biggest bang for buck.

Here's some I put together for Rtek 2.1 and 9.4:1 rotors with 93 octane. It should give you something to build off of. You could start by pulling say 3 degrees leading timing from this and keep the split calculation the same.

https://www.rx7club.com/attachment.p...1&d=1265131765

https://www.rx7club.com/attachment.p...1&d=1265131765

you'll have to adapt that to a Microtech.

to be honest with you i want about 300-350 to the wheels in the end, but if i have to run a s5 stock turbo for the time being while i get the car up and running i'm fine with that. If i don't hit 300 hp with a stock turbo its not the end of the world, but i will look for a bnr turbo.

Any ideas on a decent turbo besides the bnr, and what exhaust mani will i need? And then of course i will need injectors to match.

Alright thanks, I hate to look so lost while looking at this chart, but could you break it down a little bit for me. As in take a frame of Data and explain what it all means. I have not yet played with tunning the microtech and i will be having an experienced rotary tunner do it, but i'd like to know what i'm looking at. If you could do that, it would be great. Or if its too complicated to write all down i will figure it out. I mean i think i know what i'm looking at, but then again i might be wrong.

^ The y-axis is manifold pressure (vaccum / boost), and the x-axis is engine RPM. The most vital area in the timing maps will be the upper right hand section. Roughly 2500 RPM to redline is where the stock turbo is capable of generating positive pressure (depending on gear), so keeping the lead timing safe enough there for 9.7:1 rotors is going to be critical. The lower the number, the more retarded/less advanced the timing is in a particular cell. Split timing just determines the firing of the trailing plugs in relation to your lead timing map. If you retard the timing on the lead map, the trailing timing will also be retarded accordingly (so long as split is not changed).

The y axis is manifold pressure. Positive values indicate boost in psi, negative values indicate vacuum in inches of Hg, just like your typical autometer boost gauge. The X axis is rpm. Some of the row and column labels are weird just because of the way the rtek works (being a modified version of the factory computer).

In the leading map the values in each cell are degrees BTDC of timing. A higher number means that the plug fires earlier (more degrees before top dead center). Generally speaking timing advances as you go right along the x axis (rpm increases) but decreases as you go up along the y axis (boost increases). There's a lot more to it than that, but that's the basics. You can read more about Microtech-specific stuff in the Microtech section of the forum. AaronCake also has a Microtech with his 9.4:1 six port setup.

Split is the number of degrees that the computer waits to fire the trailing plug. So if leading timing is 20 degrees BTDC and the split value for that cell is 15, the trailing plugs will fire at 5 degrees BTDC (which is later than the leading plugs).

alright, thanks to both of you guys, That's what i thought all the values were but i wanted to make sure. I'd rather ask the question, than look like a jackass and be completely wrong

There is no "IF".

You will NEVER hit 300hp with that weak ass turbo. Sorry.

250, max unless you want to go ahead and juice your rotary with a 50 shot on top of that which i REALLY do not recommend.

OMP? Ditch it and premix? 1:100 ratio. Just leave the thing plugged in but disconnect all the bs attached to it.

6 port turbo needs it's OWN section on rx7 club.

Alright, well then i'll look for a different turbo if i can afford it. Thanks for the advice on the OMP, and i agree 6 port turbo needs a section on this forum.

You will not regret using a different turbo. It will have boost response, power, boost control and reliability in comparison to the POS stock one.

S5 6 port turbos are much less documented in this forum than S4's, I've never even read of an S5 6PT setup on a standalone dyno at 12psi with AI/E85 on the stock turbo but I bet it would be pretty close to 300whp.

They are indeed rare, but they're out there. I think there's some old posts of mine (on SonicRaT) that have details of s5 setups. I typically run 10psi with AI (60/40) on 93, although I'm not entirely using the 'stock' turbos (for the 2nd gen at least)... I probably wouldn't venture much over the 12psi mark on any car using the stock S4/S5 turbo. The pressure increase is usually more directly related to temperature rise than it is an increased air density, and on an already high compression temperature car (read S5 9.7:1), that'll hurt quick. If you have a turbo that's efficient, then higher boost isn't a problem. I run upwards of 15 on my high boost map.

With AI (100% water) and E85, I don't think I'd be afraid of hitting 18 on the stocker, that's some serious chamber cooling.

Aside from the bnr, what suggestions do you have for a turbo? also i see that you have done this, how much boost are you running?

http://www.youtube.com/watch?v=0eKOHQeNezM

Here is my s5 high compresion 6 port, with aT70 850cc and 1600cc with Microtech LT10, i still need toget it tuned since i havent have time, but my friend has already built one with the same setup but with a Holley 650 blow thru setup and he got 478hp at 22 psi, we hope to get over 500 hp with the help of the Microtech. i will try to post a link to the starup video of my car hope it works since i never posted videos here before.*

how common is it in the state to get the front compressor wheel and housing removed and a t04b housing and wheel put on there?

combine that with your microtech and 18psi you will be doing alright

slick ep is also right, you can upgraded the compresor.

The problem with that is your turbine can't keep up. You either need to clip it and destroy spool to get that much flow through it, or you just choke the thing and watch your pressure drop. Hybrids have their place, but they are ultimately limited by a crappy hot-side.

car sounds good. Alright, so then a hybrid isn't such a good idea afterall?