RJSP

Hi guys,

I have been tuning and modding my V RS for the past year, and I feel (could be wrong) that I´m starting to get close to the limits of my 12 year old turbo. I mainly use my car for Autox and DD. Boost is peaking close to 27 psi (third gear onwards) and dropping to 19 - 20 by 7700 or so rpm on 98 ron pump gas (close or a little better than your 93 mon).

These are the engine mods on my V RS:

Wisceco 0.50 pistons (8.5 CR I think)
ARP head studs
ARP rod bolts
Balance shaft delete
Tomei oil pan baffle & slicing plate
Kiggly HLA
Magnus V5 cast IM
Full Race ProStock Manifold (painted with DEI HT silicone and wrapped)
Ported and gasket matched single flapper 10.5 exhaust housing
Gasket matched Compressor outlet (Evo 5 RS turbo)
22 psi wastegate actuator
Titek V2 O2 housing
3" TBE
Fluidampr crank pulley
Okada projects coils
Magnecor plug leads
BPR8ES gapped at 0.025
Custom 2.5" LICP with custom 2.5" compressor outlet pipe
Custom 2.5" UICP
EMUSA ebay Delta-fin 3" intercooler (same as Mishimoto)
6" Zero Sports mesh air filter with cold air feed
Samco inlet hose
Hallman Pro RX MBC
GFB Respons DV (set at 50/50)
Blox engine lower mount
Evo 5 GSR gearbox
Exedy stage 2

I´m attaching the VD results from last night with 3erd and 4th gear pulls, the stretch of road was not perfectly flat, so 3erd gear was tiny bit upward and 4th gear a tiny bit downward, in both cases in the last part of the logs; so the real numbers should be somewhere in between the two pulls.

The pulls where also done with lean spool dissabled as I´m finishing calibrating the MAF. So here come the questions:

If you look at both pulls (data) the AFR is almost spot on at 1600 Hz (which is the highest calibration point) but the as the pull continues and goes beyond 1700 Hz the AFR starts richening a little, even though in the mapafr I´m trying to lean it a little as to mantain close to 11.5 - 11.6. Is this behaviour normal? Is there a way to calibrate the MAF past 1600 Hz or is just twicking the fuel map after the 1600 Hz? I have checked for boost leaks only up to 6 psi, can´t get my electric pump to go higher.

Another question, in the 4th gear pull I´ve highlighted some small rpm jumps that I sometimes see in the logs, like going 5832 - 5820 - 5883 and so on, is this normal? I´m using Evoscan 2.6.

Well, sorry for the long post and I appreciate any feedback you guys can give.

Thanks,

Ricardo

RJSP

Ok, I did another log yesterday with a few changes: Put on BPR8EIX gapped at 0.026 (wanted to see if spark would hold), changed to another road which seems more level (and is closer to home ), and the pull was done with lean spool enabled.

Eventhough I hit WOT about 130 rpm latter, there are some improvements and the airflow Hz does show a little more flow and higher loads being hit, it is also nice to see the difference lean spool makes; I´ve set it to just lean around 0.5 - 0.6 AFR. Peak boost was 26 psi, and I need for buy a MAP to log it...

The pull was smooth but in the logged data there was a logging inconsistency, a data point in the rpm logged as 4000 when it should have beed 5000. I still can´t figure why I get this sometimes and have seen this even in a stock Evo 5 RS of a friend´s. Maybe its something to do with our ECU´s and Evoscan, I´ll try Evosacn 2.7 sometime.

The attached log has the above rpm abnormality highlighted but corrected, if left as 4000 rpm (in the middle of 4953 and 5125) it shows an absurd 6xx whp peak in VD...

Well, my future plans are to slightly port the heads and add GSC S2 to the mix!

Thanks for any comments.

Ricardo

JohnBradley

iTrader: (30)

Ricardo,

I am looking at the data now. To briefly answer the question about the RPM fluctuation you are seeing those are typically minor misfires. I would go back to the tighter gap since it doesnt hurt anything.

It is very good power for the modifications, what cams are in it now?

aaron

evo4nr

kelford 272's and IX turbo would show a nice increase.

Boosted Tuning

iTrader: (12)

The RPM issue can be due to the fact your using 2byte RPM, which can have abnormal spikes in it.

RJSP

Thanks for the advice Guys, current cams are stock Evo V RS cams. Now I remmember when logging with 1 byte rpm and/or calculated rpm the "spikes" would not show in them and only show up with 2 byte rpm. I have been using 2 byte rpm because of what other people said that it was more accurate.

I guess I´ll just do a log with the 3 rpm data selected and confirm, and if still get it then just reggap the plugs a little tighter, although the car seems to pull smoothly as it is.

My plans are to improve head flow with the GSC S2 cams and kiggly springs, then afterwards go with either BBK Full or HKS GTII, something that can still keep the car competitive in Autox and make it funner for the street/track.

Thanks again for the advice,

Ricardo

Boosted Tuning

iTrader: (12)

2byte RPM is not necessarily more accurate, its just needed when revving high then 7968rpm.

RJSP

Here is an update on my car, these pulls are both on the same map and same road. The blue lines are the improvement with a 1/4 turn on the Hallman Pro MBC. The red lines are around 26 - 26.5 psi peak and the red lines are 26.5 - 27 psi, both just estimated as I don´t have a map sensor jet and only rely in the Auto Meter boost gauge for now.

The blue pull was started just a little later than the red pull, both have lean spool activated. The logs confirm the extra power with more airflow. I´m inclined to continue raising the boost 1/4 turn at a time and see if more power is to be had (verified by more airflow), but kinda don´t want to go above 28 psi on the stock turbo. Fuel is 93 oct and 0 knock counts most of the time. What do you guys think?

Cheers,

Ricardo

tscompusa2

iTrader: (22)

if you do raise the boost a bit.. you better richen it up alittle. seems pretty lean in spots .. do you have an egt gauge? old evos are so awesome looking.

RJSP

Thanks for the advise Tom, Yeah it is a little lean because both pulls are the very first pulls done with lean spool enabled, I usually log like this as it is the leanest it will be (worst case scenario), then I check with lean spool diassabled and it is set to be about 0.5 to 0.6 richer.

Don´t have EGT but the AFR´s are usually closer to 11.4 - 11.8 after that first pull. If it means anything my plugs don´t show signs of overheating or det.

Thanks,

Ricardo

RJSP

Ok guys, just to be sure my engine is in no danger of melting I did a pull with the small boost increment mentioned earlier and with lean spool dissabled, the road was different but it still shows similar power levels (red LS on, blue LS off). Most importantly the AFR is a safe 11.5 to 11.6, this shows that with lean spool at work it is leaning about 0.5 AFR, as intended. I still get richer AFR´s than intended starting right around the 1600hz airflow, but I guess it is just a matter scaling the maf a little better at that range. Thanks for the comments.

zeus1

iTrader: (19)

great looking car!! i like the V's and VI's too bad they were not imported here in the USA.

RJSP

Thanks for the comment Zeus1, we have very few Evos in Perú, many more Subarus around here. There where 17 Evo V RS´s imported by Mitsubishi in the late 90´s, and I´m lucky to have one of the not more than 10 V RS´s that are still around.

I do like the other Evos too.

Cheers,

Ricardo

Raptord

iTrader: (10)

i get the same "bug" in evoscan where the rpm drops by 1000 for one line. I'm nearly certain it's just a software bug; just take the cell where the rpm is off by 1000 and make it the average of the rpm before and after it.

IE you have the following:

4965
4005
5078

make it the following:

4965
5021
5078

RJSP

Thanks for the comment Raptord, and I agree the 1000 rpm off one line events seem to be a "bug" or something with 2byterpm in Evoscan as Boosted Tuning mentioned. Now I also always log "engine rpm" and never see those jumps in that data. I do use the average of the before/after 1000 rpm jump or just add the "missing" rpm to get a good VD graph. By the way these 1000 rpm jumps happen on maybe half of the logs I do and only in one line, usually around round figures like 3000, 4000, 5000, or 6000; always when there is a change to the next higher thousand rpm value.

The other small jumps/dives or only 10 - 20 rpm from line to line do seem to have been a matter of small missfire events as Aaron mentioned, this has not happened again since changing the plug gaps from 0.026 to 0.024, and might even go to 0.022 since I have slightly increased the boost.

I wonder about the weather effect on the power figures. We are in the middle of the summer right now at 86 °F, in winter the weather is a nice 57 °F and should bump up the power a little. According to what I´ve read here, for every 11 °F drop there is a 1 - 3 % more power; I´ll take 1% and with 30 °F change that should be around 3 % or around 10 whp more in my case... we´ll see.

Cheers,

Ricardo