Bambam7

Sorry, no pics (who do I look like, Aaron Cake?? )

Anyways.. I've been slowly but surely been building up my car for the turbo... Not a TII swap, but a turbo addition the N/A, as a power adder...

My engine is a well built up N/A one.. with 3mm seals,
and has been balanced. 100-110 psi compression.
I want to keep things under 10 psi, and about 11.5 A/F ratio. This, combined with my big intercooler, should be just fine for detonation resistance.

For fuel, I am using a TII fuel pump, 4 550 cc injectors,
the stock ECU, and an S-AFC for correction.
These are all installed. The S-AFC is leaned out by about 20-25% across the board... (for driving around right now!)

I am not worried about my AFM... so far I have only seen 60% open on my S-AFC. (so far). Hope it doesn't bottom out.

All my emmisions are removed... so my ACV is gone, and a thin plate covering it (needed for clearance for the turbo).

I have moved my rad back about 4", simply using longer bolts and some hollow pipe as spacers. This is where the intercooler will go.
The intercooler is 2 stock IC corse welded together, so it should be more than suffecient for the 8-10 psi I should be running (hopefully closer to 8).

My turbo- a good condition S4 unit. With a ported wastegate, and the twin scroll system has been removed from the manifold.
Oil supply will some from a tee at the sender unit, and drain to the side of the oil pan.
Coolant, just from the heater hose or something- that's pretty minor.

I have a Bosch BOV from a Saab, (hey, for 25 bucks? fine with me it's bigger than the stock one) I probably won't have it open atmosphere anyways, I don't want to be advertizing "turbo" to every opponent.

For boost monitoring, I have an autometer sport-comp, (I didn't like the silver pro-comp... the black sport-comp matches better) with an A-pillar mount (Too bad- you will probably see it from beside the car)
I also have a wideband 02 sensor, the DIY kit from Oz.. I just have to buy the sensor.

I am also using a stock 2 1/2 downpipe, with a gutted pre-cat.

Well, I am just waiting on completion of the spacer (this week), and the boost gauge. I hope to have everything done in the next few weeks, I'll borrow a camera and take some pics when I can.
Anyone have any questions, feel free to ask..

Evil Aviator

What are you going to do about the power brake booster?

Hmm, that fuel system is going to be pretty marginal. Well, then again, your NA drivetrain can only handle about 230bhp, so I guess that will work. I'm not sure why you bothered to port the wastegate, though. Was it because you expect a large pressure drop from the twin interoolers? Are you plumbing the intercoolers in series or parallel?

I'm not familiar with the SAAB CBV, but will probably work just fine as long as it can handle the volume and react to the weaker vacuum signal of the rotary engine. I'm not quite sure how the S-AFC will affect things, but it's probably a good idea that you are using a CBV, as an atmosphere-vented BOV screws up the air-fuel ratio upon venting if using the stock AFM. It amazes me how many people prefer the noise to actual performance.

Doph!, the Sport Comp line is of much less quality than the Pro Comp series gauges. If you still have it in the box, would it be possible to trade it for a black-faced Carbon Fiber gauge? Well, I guess it doesn't matter much. You can always get another one if it fails, and it's not like they are expensive. I had an Ultra-Lite boost gauge in my TII, and yes, it was quite visible to everyone, but I think that you will like the positioning from a practical standpoint.

Hey, once you finish tuning, could you do everyone a big favor and post a separate thread in the ECU section about how well that DIY wideband setup worked for you?

Aaron had pics.

tIIforever

hey bambam what is the website for the diy wideband 02 sensor?

Bambam7

Oh ya, I keep forgetting about the brake booster.
I'm just going to put a check valve on the brake boster line, and MAYBE an vacuum accumulator tank if I need to. I doubt it though.
I also have to kiss my cruise control goodbye, unless I get an electric motor for it.
I also put tiny hose clamps on all the vacuum hoses while I had the manifold off- I don't want any under there popping off!

I ported the wastegate to keep boost creep down to a minimal. With the relatively high compression of my engine, I don't want a problem with keeping boost down!!

I don't see how porting the wastegate relates to pressure drop accross the intercoolers... but they are welded in series. I would have preferred parallel, but again, I'm not too picky about loosing 1psi of boost on my high-comp engine, it's already pretty peppy. There was just NO room for the 7" thick core anywhere.

The gauge itself I havn't picked up yet, I'm waiting for the pillar mount. The gauge is a regularly stocked item at my local shop, so I am under no obligation to buy it... So I should go pro-comp? Reliability isn't a problem, it's warranteed, but accuracy is key!

DIY O2 website is http://www.techedge.com.au/vehicle/wbo2/default.htm

tIIforever

cool thanks

Evil Aviator

I think that you will get closer to 3psi drop @ 10psi from that series
intercooler, but I guess you will find out shortly. To me, this means
that to run 10psi at the manifold, the compressor will need to output
13psi. I was thinking that the ported wastegate may help with the added boost level, but then again there will not be so much of a boost creep problem because the intercooler will be sucking up all that boost. Also, that stock downpipe is going to keep the boost down some, so you may not even get to 10psi manifold pressure. Maybe I'm totally off base here,
but that was my thinking on the wastegate. It will be interesting to
see what happens.

What do you mean by a 7" thick core? You could make a parallel
intercooler setup by using y-pipes to connect them to common input and
output pipes. I guess this would be difficult to mount if you retained the stock end tanks, though.

Yes, I would cancel the order on the Sport-Comp gauge, and get a
mechanical Pro-Comp or Carbon Fiber gauge instead. Anyhow, you
can do whatever you like, but here is a quote from the Auto Meter representative in response to my question about the quality of the Pro-Comp series (Pro-Comp, Ultra-Lite, Carbon Fiber) vs. their other gauges:
"Yes, the "upper end" of our gauges are the most dependable, most accurate, and longest lasting out of all the gauges that are made.

Ward
Tech/Service"
http://www.autometer.com/hp/index.html

Roy James

Why dont you run a Volvo FMIC? sorry if this has been discussed and im not too familar with turbos and things, but that **** is huge, and looks pretty thin so it should fit in there. Again, sorry if im way in left feild, just a suggestion. Looking good man! you guys are tempting me too much!

rico05

So you're finally joining the Dark Side of Boost hunh? We must never speak of you again . I was wondering when you were gonna start this project. Anyway good luck, and keep us posted!!

SoloIIdrift

damn, another "pure N/A" guy goes over to the dark side...

WestJaxVert

Can you elaborate on this a little more for an idiot such as myself; particularly the parts about the weaker vacuum signal and screwing up the air-fuel ratio. Thanks.

Dan

Aaron Cake

iTrader: (1)

Evil Aviator: Ported wastegate=lower boost. Porting the wastegate on a S4 turbo is a safety measure because the stock orifice is way too small, which leads to boost creep.

Bambam7: Glad to hear you are starting the project...But you do need pictures, especially of that intercooler. I am really interested in how that turned out.

If I had known you neede a BOV, I could have mailed you a Saab BOV for the price of postage...I have a tonne of them around as I used to use them in air powered spudguns.

It will also probably be a lot easier to use the coolant lines at the intake instead of the heater hose. The intake hoses are the perfect size...I have a pic of mine, but have not yet prepared it for the web...They really do fit very well.

One more thing. The autometer boost guages are not very accurate...Usual error is a few PSI in either direction. I have an Autometer boost guage as well, so I face the same problem.

Evil Aviator

Yes, so I don't understand why it is ported with this setup. How is the turbo ever going to create enough boost to cause creep with that 2.5" DP and restrictive FMIC? The only result that I see of the wastegate porting in this case is a constant leakdown condition, which is just going to hurt the acceleration which is already going to suffer enough because of the disabled twin scroll effect. Just because you set a wastegate for x-amount of max boost, it doesn't mean that the turbo will ever produce that much. Please explain how this system is going to reach 10psig manifold pressure, and then I will understand the porting.

BTW, my Auto Meter Ultra-Lite gauge was quite accurate enough for street use. If yours isn't accurate, then you should take it back for exchange or refund. However, I wouldn't expect the Auto Meter gauges to work as well as the $350 boost gauges from HKS, Apexi, etc.

Well I guess I'm an idiot, too, so maybe Aaron can explain the wastegate issue. I'll give a stab at the CBV, though...

Bypass valves (BOV, CBV, TBV, etc.) generally vent when a vacuum signal is received from a tube that attaches to the intake manifold. Is this how the SAAB CBV works? If so, then it is designed to see a much stronger piston-engine vacuum signal, and it may not react properly to the weaker rotary engine vacuum signal. I think it's worth a try, though. If you do have a problem with the different vacuum signal, then a weaker spring should fix the problem.

The stock AFM meters the intake air to determine the correct air/fuel ratio. If a lot of this air is vented by a BOV, then the ECU will still add the fuel that it thought it needed because it has no idea that the air is gone because there is no way to sense it. This will obviously cause a rich condition every time that the BOV vents to the atmosphere. The rich condition will cause the engine to bog, stumble, or hesitate every time the BOV vents. However, if the air is vented back into the system between the AFM and compressor (as on the stock TII setup), then the air is not lost, and the air/fuel ratio remains correct when the valve operates. Many aftermarket EMS systems use a Speed Density or Alpha-N system instead of an AFM, so this is why an atmospheric-vented BOV works fine with them.

Felix Wankel

I always hear that about open BOV's, but what I want to know is why would be sending that much fuel when the throttle is shut?

FWIW, my car hs no stumbling or hesitating problems with a TurboXS valve.

Aaron Cake

iTrader: (1)

Porting the wastegate is simply a precaution. The S4 hole is very small, and even stock setups can experience boost creep under certain conditions. The porting may not be needed, but it may come in handy that one cool summer evening...

FWIW, the S-AFC has built in functions to compensate for open vented BOVs...I will be using this function since I have the Apex'I BOV.

VtekEater

Come on guys get them running already
Hey Bambam how much did everything come out to
for the WB minus the O2 sensor?? I would have gotten one but they said they where all out.

Bambam7

The kit was less than $100 CAN I think.... I think it would be around 60-70 US.
The sensor is 130 US.
So about $200 total. You also, of course, need a soldering gun, solder, and a few little odds and ends (pennies at radio shack) like an adjustable resistor (for testing) and a AA battery and such....

Evil Aviator- I am expecting to see 8 PSI.
I may have a 2.5" DP, but the rest of the exhaust is straight through, and the pre-cat in that DP is gutted.
I also have will have a free flowing intake, equivelant to the TID mod.
Don't forget my street port as well... I should see much more boost than stock once over about 3500 rpms.
Of course, this system was NOT designed for max boost. Far from it. It was actually designed to limit the max boost I will be seeing, because of my high-comp engine.
The exhaust will be exiting the chambers at higher velocity than the lower-comp turbo engines.... increasing the turbo speed.
The removal of the twin scroll, from what I've heard increase boost at higher rpms, dure to higher flow.
Have you had any first hand experience with it? I've heard that the low end sacrifice is minimal, if at all- but again, it's just what I've heard, I have no actual experience.

Evil Aviator

Wow, that's good. I didn't know that the S-AFC had that function.

No, I haven't done this, as I would just slap a T-61 on there if I wanted more boost, LOL. In theory the removal of the twin scroll function should have the same effect as increasing the AR, which will slow the turbo, increasing flow at higher rpm's but also increasing spool-up time. It will be interesting to see how it works out.

Felix Wankel

You can definately tell the difference with it out. Mine took a few hundred more RPMs to reach full boost. The clipped turbine wheel seemed to make it take even longer.

NZConvertible

I dunno about rotaries having “weak” manifold vacuum, mine goes plenty low when I lift off, well under 20inHg.

Bambam7

About the twin scroll...
I don't really have a choice but to remove it. How else would I actuate it? There is nothing that I can get a vaccum signal from at 2700 rpms, without getting an RPM actuvated switch.
I just thought of an idea using a spare aux port actuators (s5 ones extend with pressure!_... I'll post that in a new thread right now...

Felix Wankel

I think its too much of a hassle to bother keeping it. If you're trying to get in boost at 2000 RPM, you need to learn how to drive a turbo rotary anyhow

Bambam7

Hehe, try driving my heavily ported N/A, with no aux port actuation, and the VDI locked in high range....
It's on it's face untill 5500 rpms! (Then it sings to 9000 in a flash though...)