FMIC on a small turbo [Archive] - High Altitude Imports

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Brian

08-07-2002, 12:59 PM

Ok I figure the DSM guys should be able to answer this one fairly easily. I have a very small stock turbo (ko3 sport). With my chip i'm pushing 21 or so psi of boost through it in the mid-range of the rpm band. There is quite a bit of issue with heat soak after driving briskly for any amount of time. The VW guys seem set on the thought that a FMIC would be too large for the stock turbo and hurt performance. I feel that this is false as do a few others. The biggest problem is they are all basing this off of the opinion of a few that have never tried it. As a matter of fact no one is running or has tried to run a FMIC with the stock turbo. I would imagine there is the potential for a bit more lag, but on a turbo that spools by 2000 rpm that isn't a big deal to me. Besides that shouln't any negatives be ouweighed by the fact that the aftermarket core should ahve a much higher flow rate and efficiency rating? The stock IC is only something like 50 percent efficient which sucks. What do you guys think?

nolimitsoldier

08-07-2002, 01:03 PM

As soon as I get the cash, I'm getting one. even thought it'd be on my stock turbo, it seems that better intercool effiency and a cooler intake charge would be good, no?

Brian

08-07-2002, 01:09 PM

That's my thought at least..........

Now I do plan on doing a t3/t4 upgrade in a year or two so I would definetly need it then, but i'm thinking it might be a good idea in the mean time as well.

V8SpankR

08-07-2002, 01:23 PM

I know on a 2nd gen DSM using a front mount with the T- (too small) 25 does hurt performance. I think the fmic is too big for the pressure that the turbo generates and I think it has too much of a pressure drop and slow down the spoolup time.

john

08-07-2002, 01:23 PM

Get one. The benefit of the cooler charge FAR outweigh the "added turbo lag" of a front mount. The compressed air is moving thru the system in excess of 100 mph - how long will it take to fill a FMIC?

I was amazed to see how TINY and SMALL the SMIC is on the A4. It looks like an oil cooler. :(

You are getting 21psi out of that K03? Woof! What's stock boost?

turbodScooby

08-07-2002, 01:25 PM

Im pretty sure that one of the guys that works at McDonald VW has a Front Mount on his Golf, which has still has the ko3 in it. There is room for loss, and why not do it if you plan on upgrading.

V8SpankR

08-07-2002, 01:29 PM

Brian

08-07-2002, 01:31 PM

Originally posted by john
Get one. The benefit of the cooler charge FAR outweigh the "added turbo lag" of a front mount. The compressed air is moving thru the system in excess of 100 mph - how long will it take to fill a FMIC?

I was amazed to see how TINY and SMALL the SMIC is on the A4. It looks like an oil cooler. :(

You are getting 21psi out of that K03? Woof! What's stock boost?

Yeah, I have the same mini-me intercooler on mine :D.

Stock boost is between 10 and 12 psi depending on rpm and gear. With the apr 93 program I see 20 or so from about 3k to 5.5k then it starts to drop off to 15 or 16 near redline. It didn't hold that much boost until the other day when I got my new diverter valve.

john

08-07-2002, 01:35 PM

And a diverter valve is a BOV?

Paul - yeah! Those 2g guys SUCK! :)

john

08-07-2002, 01:39 PM

What diverter valve (BOV?) did you get? I was told that the Audi TT valve works great and is only $23 or so...

nolimitsoldier

08-07-2002, 01:40 PM

Brian

08-07-2002, 01:50 PM

Originally posted by john
What diverter valve (BOV?) did you get? I was told that the Audi TT valve works great and is only $23 or so...

I went with a Hyperboost DV. It's fully rebuildable, has a metal piston and holds quite a bit of boost. A dv is pretty much like a BOV, but it vents back to the intake instead of atmosphere. I think it's the same as whats on the DSM's stock.

As for teh TT valve I would stay away from it unless you don't plan to run much more than stock boost. Like the stock DV it uses a rubber diaphram to open and close so it ahs a tendency to leak. I hear they hold up much better than stock, but I figured I should go all the way. I get pretty good pricing on the HyperBoost stuff anyway so it was a good deal. Here is a link to some more on that DV. http://dubparts.sportcompactracing.com/product_info.php/products_id/43?osCsid=12da77793691ce98268bfcd6c96f2d23

Brian

08-07-2002, 01:55 PM

Well if we decide to get FMIC's we should talk to mark on the board about bending us the piping. The ATP front mount without piping sells for 475.00 with piping it is 975.00 :eek:

nolimitsoldier

08-07-2002, 01:59 PM

yeah, it's EXPENSIVE, but sweet!!! If you decide to do anything with that, let me know because I would be very interested!! BTW, did you get a price on the AEM's?

B16crxTurbo

08-07-2002, 03:12 PM

I would say go for the FMIC. Way back when, when I had the Greddy T-25 with the front mount on my car, it still had insta-boost. I didn't seem to notice any kind of noticable lag when my car was set up that way. Besides if you are nearing the outside of the efficiancy range of your turbo, the added benefit of lowering your intake charge temp should show noticable performance gains.

davidm_sh

08-07-2002, 03:55 PM

Originally posted by B16crxTurbo
I would say go for the FMIC. Way back when, when I had the Greddy T-25 with the front mount on my car, it still had insta-boost. I didn't seem to notice any kind of noticable lag when my car was set up that way. Besides if you are nearing the outside of the efficiancy range of your turbo, the added benefit of lowering your intake charge temp should show noticable performance gains.

That's exacally what I was thinking:

Cons - added lag due to turbo having to "fill up" the extra piping and intercooler space.

Pros - You HAVE to be running that turbo WAY out of it's efficiency range UP here running near 20psi of boost. So the extra cooling will DEFINITLY help. I thought I was bad boosting to 18-19psi and having the turbo taper off to 17psi by redline. Which in my book tells me my turbo is getting pretty inefficient. BUT yours tapers down to 14-15 from 20psi :). Good luck. I hope they have good warranties on those turbos ;) [heh]. But when it blows that's just a good excuse to get a new one isn't it.

jojo

08-07-2002, 05:43 PM

Get the FMIC, it's not going to hurt you. And at those boost levels I wouldn't be surprised if it improved your response times.

Brian

08-08-2002, 04:17 PM

Originally posted by davidm_sh

Pros - You HAVE to be running that turbo WAY out of it's efficiency range UP here running near 20psi of boost. So the extra cooling will DEFINITLY help. I thought I was bad boosting to 18-19psi and having the turbo taper off to 17psi by redline. Which in my book tells me my turbo is getting pretty inefficient. BUT yours tapers down to 14-15 from 20psi :). Good luck. I hope they have good warranties on those turbos ;) [heh]. But when it blows that's just a good excuse to get a new one isn't it.

Well one thing that helps out is that the boost level is not constant. Since these cars are throttle by wire the ecu has full controll of the boost at any given RPM. That being said the chip designers have figured that the turbo can handle 1.4 bar in the midrange, but not in the top end for apparent reasons. At 5000 rpm or so the ecu only calls for 1 bar and tapers off to .8. Now I am making more boost than this at the top, but my point was it's not only tapering off from the ineficiency, but also from the ecu itself knowing that it needs to back off boost. The boost also varies between gears. In first gear I make 16-18 second about 20 then 3rd and 4th spike to 21. The traction control system cuts boost if the tires spin, ect. It's a fairly complicated ecu VW has here.

SleeperZ

08-08-2002, 05:58 PM

Originally posted by 99SIVTEC

Well one thing that helps out is that the boost level is not constant. Since these cars are throttle by wire the ecu has full controll of the boost at any given RPM. That being said the chip designers have figured that the turbo can handle 1.4 bar in the midrange, but not in the top end for apparent reasons. At 5000 rpm or so the ecu only calls for 1 bar and tapers off to .8. Now I am making more boost than this at the top, but my point was it's not only tapering off from the ineficiency, but also from the ecu itself knowing that it needs to back off boost. The boost also varies between gears. In first gear I make 16-18 second about 20 then 3rd and 4th spike to 21. The traction control system cuts boost if the tires spin, ect. It's a fairly complicated ecu VW has here.

I'm just thinking that folks used to complain about cars becoming computerized...now they REALLY have stuff to complain about. I'll stick with my "old school" FI from the eighties, thank you. A computer is good for calculating air and metering fuel, maybe timing advance, but when it comes to monkeying with my boost level NO THANK YOU :gapteeth:

02GTI1.8t

08-08-2002, 06:18 PM

go with the fmic. I know there are some people on the vortex with the k03 and a fmic and they dont seem to have any problems. I doubt you will see much more lag, and the stock ic is tiny. I think the pro's by far outweigh the con's. the only bad thing ive heard is you have to cut some of the bumper support or something to make it fit with the stock bumper

BoraTurbo

08-08-2002, 08:07 PM

My buddy at mcdonald has a fmic on his stock k03 sport. He has the same mods that i do plus fmic and drag radials and he can do a 14.3 at bandi. he did a 14.1 at pmi on the race mod on the apr.