Outer Limits 4x4 Board

G-day All , just wondering if anyone has put a unichip in there Big-Rig , If so are they worth it $$$ and claimed power increase . I have been quoted $1100 drive in drive out Mike H , are you reading this

Hello Andy, I used to work for one of the biggest aftermarket EFI chip suppliers in Australia. I was also involved with a lot of custom chipping on dynos etc.

The Feroza (as you'd already know) has got fuel only injection- the EFI computer doesn't control the timing. All the Unichip will be able to do is adjust the fuel injector pulse width- so unless your Feroza is running lean, or you've changed a cam, then you'd get a minimal power gain just from the Unichip. It could however allow you to advance the timing further on the distributor before you got detonation, which would give you a power gain. The power gained from aftermarket chips is usually from the timing being advanced- most leave the fuel mixture alone.

From memory Mike had a repacement cam in his Feroza when he got the Unichip and would have needed it for this reason. I've heard EFI Commodores with cams changed running with the standard program and they usually aren't too happy....

Personally I'm thinking an adjustable fuel pressure regulator could be useful for the Ferozas in stopping detonation. They're a lot cheaper and will allow you to supply more fuel without mucking around with the electronics.

Just some thoughts on the subject.

Kriky , Thanx for that murcod , see if you don't ask , you'll never know

Ok , got another question , got a guess on how much the fuel regulators are worth and do you have to change the fuel rail , and anything else that I need to know to ask the person I'm going to suck into fitting it for me

Andy, I've never bought an adjustable regulator (or fitted one), but I believe they are around the $200 dollar mark for a good rising rate one. Malpassi are supposed to be a good brand. They are just plumbed in line with the fuel return line going back to the tank (fuel pressure is controlled by limiting the flow back to the tank). The standard fuel pressure reg is bolted on the end of the fuel rail, and I don't see why it would need to be removed. Just disconnect the vacuum line running to it from the manifold, and then the adjustable one would be plumbed into the fuel return line and the vacuum line from the factory regulator connected to it.

As I said, I've been thinking about doing it, but I don't know for certain that it will cure the detonation..... It would be good to get the mixtures checked using a mobile air fuel ratio meter first- that will tell if the engine's leaning out when it detonating (my bet is that's what's happening though).

Another really cheap option would be to play around with the EFI air temperature sensor resistance. When the air is colder it is denser, so more fuel is injected by the EFI computer. So if the resistance of the air temp sensor is changed the computer will be fooled into injecting more fuel on hot days when detonation is worse.

Out of interest what have you got your timing set too? I can't run mine past 2 degrees BTDC except on the coldest of days (even with 98 octane fuel). There's a steep hill on the way home and second and third gear will detonate on it really easily- if I didn't have to drive up it every day I probably wouldn't have problems!

Hmmmmm.... Here's a bit more info on the Malpassi regulators:

http://www.injectionperfection.com/html ... ators.html

http://www.injectionperfection.com/html ... ist_3.html

Looks like $160 from the second list. You would just need the normal Malpassi EFI reg too- the rising rate one I mentioned earlier is for turbo engines.

Check out the engine in the Charade below- a turbo HD-E Detomaso engine, straight fit into the Feroza!

http://www.cardomain.com/member_pages/v ... _id=309744

Thanx for all the info Dave , i'll do a bit of homework and see what I come up with , " watch this space "

Keep me updated on your progress Andy- the detonation really p****s me of! I'm surprised nobody else has found a simple fix for it yet (apart from retarding the timing)

OK Andy another amendment on what I said :

The standard fuel pressure regulator would have to be removed. If it was left as I said above then it would give max pressure constantly. It's relatively easy to access it at the end of the fuel rail below the throttle body.

Here's a pic:

G'Day Andy,

Sorry for the delay - only log on to this list every couple of weeks or so....I do check my email every day though, so if you ever do need a faster response then just email me.

Anyway - Unichip. Overall I thought it was a good mod. It certainly did what they said it would - & it really improved the "drivability" more than the Dyno figures indicate. The increase in low down torque was particularly noticable.

Just as Dave said - they do advance the timing, & they adjusted the Fuel Curve to suit this more aggresive timing. One thing they certainly did cure was the Engine Pinging ;-) You can choose what Octane Fuel you have the Unichip tuned with ( & obviously affects performance & what fuel you have to use. ) being the greedy bastard I am I opted for Optimax ( RON 98 ) & got an excellent result - but was locked in to only using Optimax ( or BP now does an Ultimate 98 Fuel ) or adding an Octane Booster Fuel Additive of which Nulon was easily the best. Didn't worry me too much as I was already only using Optimax anyway ;-)

Yep - I did have a MRT reground Cam in mine, but I really felt this was the least useful mod I did. As it was reground from an original one it really wasn't that different from standard, & only really helped above 4000 RPM, & was actually worse from idle !! - another reason I went the Unichip to try & get some low down grunt back !! ;-)

Just to comment on Daves comments on pinging / fuel regulation etc. We found when tuning the Feroza that it is really touchy when it comes to Fuel & Heat - even after only a few runs on the Dyno the heat soak into the Intake Manifold was causing the temp sensor to tell the ECU to back the fuel right off to prevent detonation - this was a constant problem during the whole tuning process. If we did a few runs then let it cool - then give it another run, the results were way off what they should have been. We also found the stock Feroza was running quite rich from standard - we actually has a much leaner fuel curve in the final tune & I actually got a noticable fuel saving.....with no pinging :-)

If you haven't done the Extractors / Sports Exhaust I probably wouldn't do the Unichip, but if you have, with your Snorkel as well it may be worth thinking about.

All the info is still on my site - including the Dyno chart.

I also put in a later post ( I'm working backwards here !! ) that I still have the Unichip module out of my Feroza - I was hoping to put it in the Hilux Surf Turbo Diesel but they aren't compatiable. If you are interested you can have it for $50 - I think they are about $200 - $300 out of the $1100 for the full install. Might save you a few dollars ;-) Let me know if you are interested.

Later - Mike H.

G-day Mike , good to hear from you and thanx for the info above , " Our Feroza " does come complete with Extractors and Sports Exhaust , I bought the last set of Genie headers in WA , I'm keen on getting your Unichip module , I'll mail you in a few days

Thanks for the info Mike. After reading that I'm tempted to experiment with a fixed value air temp sensor in the warmer weather to see how things change. I've got the resistance values for the air temp sensor, so it won't be too hard to do.

Do you know what sort of advance you were able to run with the Unichip once it was all finished? Also, did you look at getting a custom chip done for the standard computer?

Andy, any more updates on your progress?

Not as yet , I've been flat out with work and I've had to pave a new driveway ready for our camper trailer, it's funny how all my mates are busy the minute I mention the word " paving "

Andy have you seen this? Looks pretty good - the only down side is it doesn't control timing- but it would do everything a Unichip could and more!

http://www.outerlimits4x4.com/PHP_Modul ... php?t=7425

G-day murcod , Think I'll file that in the " to hard basket " Good thought though . once I finish blowing my dough on my trailer and finish putting floorboards down in our house I'll think about the " Chip "

Hey Mike,

If that offer on the chip is still on I'll take it off your hands...

FerociousFeroza wrote:Hey Mike,

If that offer on the chip is still on I'll take it off your hands...

G'Day Paul,

The Unichip is already sold.....sorry 'bout that
I can do you a really good deal on a Momo Steering Wheel & Gear Knob though....

Later - Mike H.