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I am interested in getting my car tuned with the mods I have, since I don't have any future ENGINE mods in mind. So here's my question:

Would it be wise to purchase and have someone tune a Apexi S-AFC to control the air and fuel, and a SBC-ID to control boost? Or go with a unichip or UTEC to control all three?

I could go with a Vishnu Unichip, and have Vishnu tune it, since I live near them. But I am going to go with the SBC-ID sometime next year anyway, to control my boost settings.


And if I am going to buy a SBC-ID for boost anyways, wouldn't buying a S-AFC be easier to hook up and tune than a piggyback type chip. There are a few tuners out here in the Bay Area that can tune the S-AFC.

If I am not making sense, I am sorry. I just want to have my car tuned properly.


Please help me in my confusion. Its been a n00b day.:D

Kurlee Daddee
(THE ORIGINAL)
 

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UTEC is the best solution in my mind right now (I'd love to see what Shiv has up his sleeve for a programmable engine management system though - he gave us a quick blurb on it when he tuned some locals car here when on vacation and it sounds GREAT!) because of it's tunability.

S-AFC + SCB-id would be second in my book...

Unichip last - because you can't actively have a hand in "tailoring" it to your specific vehicle.

If you can get a dyno tune and burn it to the chip you're golden though...
 

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I would use the SBC-id and a UTEC personally. Yes it is more expensive but you'll hav ethe boost control of the SBC with the fuel/timing control of the UTEC. Unichip is aso a good choice if you can get it at a good price since the UTEC is kinda pricey.
 

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I would go with the apex-i s-afc + blitz sbc-id, the s-afc is only like $300.00 max , you can probly pick it up a lot cheaper used.

I would bet you could pick up 15-20 hp just from a real good dyno tune with the s-afc. Our cars run very rich stock, leaning it out a bit will help tremendously!

as far as timming control goes, our stock computers are still ultimatly in countrol, and in most cases any timming you add will slowly be manipulated by the stock ecu anyway.

how much HP will timming give you any way? not much I bet.
and If you tune your car corectly and monitor the real time gauges (egt, a/f ratio, boost) and you dont run a stupid amount of boost (14.7-16.5 on stock turbo is perfect) and (run on sentance) set up gain on the sbc-id correctly, your car will not pull timming!

so unless someone wants to give me a uteck for less than $300.00 I'm not buying it!

I'll take the extra $700.00 i saved and buy a set of 17" rota subzeros black center w/ polished lip wrapped in sticky gumballs!!!

just my opinoin
 

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Nice thoughts! I'm in full agreement Jetguy...

I'm thinking of getting a S-AFC and a Delta Dash and roadtuning my setup (no AWD dynos within thousands of miles and I'm surrounded by the Pacific Ocean). :D

I'd love a UTEC - but the wait and the $ make it a less than feasible solution for me. :(

Either that or I could just say "toss the tuning I'm just going to throw a stage 4 at it! :D"
 

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One thing about the UTEC though is the ability to gank it and be that much closer to stock again. Also I like the idea of mutiple maps, a programmable solenoid controller (for that ic spray :)) and rev controller. The UTEC seem expensive, but the peace of mind may be worth it.
 

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I have used all three. I had the stage 2 unichip on my car for 6 months with no problems at all. I then ditched the unichip for a Blitz sbc-id and Apex S-AFC and installed a Blitx FMIC, PE1818, and STi injectors. I got it tuned on the dyno and it made good #'s but it ran like **** on the street. It was really inconsistent and I know had timing issues. I now have the UTEC with a untuned stage 4 map and the car runs great and it's not even tuned yet. So I would say go for the UTEC if you got the money.
 

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jetguy said:
as far as timming control goes, our stock computers are still ultimatly in countrol, and in most cases any timming you add will slowly be manipulated by the stock ecu anyway.
Actually that is true to some extent except for the UTEC since it does it's own timing map and does not mess or interact with the stock ECU at all.
 

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These things are all toys and not necessaties... which means if you can drop $300 on an afc, then you can wait longer, save more money and go with UTEC. It's not a matter of money, just a matter of how long you're willing to wait for high quality. My .02. BTW, I'm broke and I still look at it this way!
 

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hobbzz said:
These things are all toys and not necessaties... which means if you can drop $300 on an afc, then you can wait longer, save more money and go with UTEC. It's not a matter of money, just a matter of how long you're willing to wait for high quality. My .02. BTW, I'm broke and I still look at it this way!
Something appeals to me about the closed-loop and more stable boost control of the UTEC versus the SBC-iD. Mine tends to not be very consistent day to day. If I had the money now, I'd probably sell the SBC-iD/Power-iD combo and get a UTEC.
 

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I sold me unichip for a s-afc/avc-r combo because my unichip was causing the ECU to pull 10 deg of timing after a while (and the tuner could figure out why). It's a lot better to be able to fine tune your car from day to day. I will say that is more midrange with the unichip timing advance, but other than that I have no complaints. Plus, $1K is a lot for a non-standalone IMO.
 

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TypeC said:
I sold me unichip for a s-afc/avc-r combo because my unichip was causing the ECU to pull 10 deg of timing after a while (and the tuner could figure out why). It's a lot better to be able to fine tune your car from day to day. I will say that is more midrange with the unichip timing advance, but other than that I have no complaints. Plus, $1K is a lot for a non-standalone IMO.
Do you guys mean to tell me the SAFC/various open-loop boost controllers will do everything a UTEC can? Is it fair to compare the two?
 

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I'm reading this thread and I'm a little lost...

If you have both an EBC and a chip/UTEC, how does the chip or UTEC alter boost? Wouldn't the Chip or UTEC need to interface w/ the EBC somehow?

Or maybe the real question: is an EBC a good option if one already has a Chip/UTEC? would the EBC just mess up the programmed maps?

I think I understand what these components do separately, but am confused how they work together. At first I thought the chip/UTEC works from data sent by the sensors (therefore, if EBC punches in more boost, the chip can compensate), but I recently learned that under load the input by the sensors are ignored and pre-programmed maps take over.

Sorry for introducing newbieness into a technical discussion.
 

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QuickSilver said:
I'm reading this thread and I'm a little lost...

If you have both an EBC and a chip/UTEC, how does the chip or UTEC alter boost? Wouldn't the Chip or UTEC need to interface w/ the EBC somehow?

Or maybe the real question: is an EBC a good option if one already has a Chip/UTEC? would the EBC just mess up the programmed maps?

I think I understand what these components do separately, but am confused how they work together. At first I thought the chip/UTEC works from data sent by the sensors (therefore, if EBC punches in more boost, the chip can compensate), but I recently learned that under load the input by the sensors are ignored and pre-programmed maps take over.

Sorry for introducing newbieness into a technical discussion.
No need to apologize, the only dumb question is the one not asked. That's what forums are for afterall!

To answer your question, I had Garret @ World One explain this to me yesterday. The UTEC (not Unichip, be careful not to mix the two they are not the same!) has a closed-loop boost controller built in. This is very similar to what the factory ECU has (which is hard set at 14.7 or whatever it may be). Here is a blurb from a page I found explaining how the Impreza's ECU controls boost stock:

"Boost pressure is controlled by software in the ECU - the ECU measures manifold pressure, using the MAP sensor, and then regulates boost pressure using the wastegate solenoid. (As well as manifold pressure, RPM is also used as part of the input map for boost pressure to reduce boost at high RPMs.) The actual configuration of the turbo tubing and components consists of a pressurised hose from the turbo to the wastegate actuator with a T-piece off to the wastegate solenoid that bleeds air to the intake side of the turbo under the control of the ECU. (Out of interest this is a slightly different arrangement to other cars such as the Nissan Skyline.) The wastegate solenoid is a non-linear device - it's either fully open or fully closed - so to allow more control (and essentially make it linear), it is pulsed open, then closed, 14 times a second (you can hear it clicking from just above tickover in the off-side of the engine compartment). As boost pressure rises, the time it is closed for increases in proportion to the open time, which provides more pressure on the wastegate actuator, which in turn allows more air to bypass the turbo, thus reducing turbo pressure. The resulting system is a classic closed loop control system. "

Open loop in comparison takes the sensors out of the picture. This is how the SBC-iD and AVC-D by Apex'i is designed. Here's a blurb on FastWRX I found about open-loop:

""Open loop" mode is the only place where fuel settings can affect power. At full throttle, the computer does NOT read the oxygen sensor, but instead just looks up a table of air flow vs. rpm, and adds fuel according to the value found in the table. A careful tuner could change the fuel mixture to increase power, since the factory settings are conservative, especially at high boost levels, where extra fuel is added to the cylinders for cooling. Leaning out the air/fuel mixture can increase horsepower in these conditions"

Matter of fact, that whole page has a useful explanation on ECU reprogramming:

http://www.machv.com/ecurep.html

So, then leaves the question what's the difference between running an EBC with the UTEC versus using the UTEC's built-in closed loop controller? Basically the ability to change it on the fly.

It is also my understanding the closed-loop control works much better. I don't know if you experience this, but my EBC is flaky. It never is 100% consistent.

Does this help, others comment if I'm on the dot?
 

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Thanks Hokieitr :)

That's a lot to absorb...I'm at work right now, so can't muster the time or brain power to do both. I'll ponder during lunch.

If others have more to add, I'd appreciate all the help I can get understanding this topic.

I'll post more q's as I think of them.
 

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QuickSilver said:
Thanks Hokieitr :)

That's a lot to absorb...I'm at work right now, so can't muster the time or brain power to do both. I'll ponder during lunch.

If others have more to add, I'd appreciate all the help I can get understanding this topic.

I'll post more q's as I think of them.
You know the sad thing?

So am I :)
 

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typeC..how do you like the s-afc/avc-r combo? ive been thinking about that one alot lately.

anyone have any experiences with the blitz spec r yet? anyone combo that with the s-afc? or is it necessary with that one?
 

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So based upon hokieitr's post, there is no real need for an EBC if one opts for the UTEC???

the EBC would only prevent the Utec from altering the boost to meet a certain map. On the fly boost control (a key aspect of the EBC) would not be necessary since you can change between 5 different set-ups on the Utec (currently difficult to change, but I hear a satelite control is in the works for the Utec to allow easier access).

The Utec generally gives the user control over boost, timing, and fuel/air ratio, which will not be later negated by the ECU (a flaw of uni-chips). Adding a boost controller would only take away from the Utec's effectiveness.

I guess one could couple an EBC w/ Apexi's A/F controller and get a similar result (but would still lack the timing control).

now would the Uni-chip and EBC be worthwhile, or would it be the same situation as w/ the Utec? Wouldn't altering the boost (a la EBC) "mess-up" the ideal map burned on the chip?

BTW, I don't have an EBC, but was seriously considering one. Now I'm not that sure.
 

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QuickSilver said:
So based upon hokieitr's post, there is no real need for an EBC if one opts for the UTEC???
You obviously haven't used the Utec/Unichip boost control before. It works but isn't NEAR as good as a good high end ebc (blitz, apexi). It does control part throttle boost, but it's essentially a bleeder BC which doesn't spool as fast a ball and spring mbc or a solenoid ebc. That is my only complaint about it.

typeC..how do you like the s-afc/avc-r combo? ive been thinking about that one alot lately.
I like it a lot. I cant sync the avc-r and s-afc settings rpm by rpm.

Ultimately, the Utec will give you better fueling/timing control (of course), but the s-afc/ebc setup will work well. A friend runs [email protected] with s-afc, stock ecu, and datalogger (VF22 no nitrous). It can work well.

On thing to remember with the s-afc is, if you take out too much fuel the ecu will advance timing a bit. You can pull the timing back to where you want it with a Delta dash.
 
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