The Q4 in standard trim has 180 BHP & 200 lb/ft torque. The ca has adjustable fuel pressure though you probably won't have to change this unless you are after serious power. A plug in chip can give you up to 260 BHP without any other mods. For quicker spool up of the turbo an exhaust manifold & exhaust system can be fitted which will again increase power & reduce the aceleration time. Beyond a chip, exhaust, manifold & air filter you will need to ensure your clutch & transmission can take the power.
Yann, get a Squadra chip like the ones from the Alfaowner online shop -with a Q4 you get a superb bhp/torque increase for quite a small amount of money. Go to the online shop and read all of the information, there are even links to some fitting guides for the various 155s if I remember correctly! Squadra will give you details of your nearest dealer.
Yann.. I've just fitted a Squadra as I couldn't really justify a fully mapable chip. As long as the engine & hoses are healthy it's great! I hope to get a rolling road graph sometime so I can compare the std & squadra graphs. For £200 you can't go wrong!
I recently had my Q4 tested on a rolling road?(Dyno with 2 rolls)
It has a squadra-chip, an RVS-exhaust and a custom made airfilter. All the three kats are still in place.
These are the figures:
RPM KW wheels Verm.[KW] Koppel [NM] Hp
2000 45,82 55,90 263,20 76,02
2500 71,71 87,49 329,57 118,99
3000 90,64 110,58 347,12 150,39
3500 124,50 151,89 408,70 206,57
4000 133,46 162,83 383,36 221,49
4500 155,38 189,56 396,71 257,80
5000 159,36 194,42 366,19 264,41
5500 157,37 191,99 328,74 261,11
6000 145,42 177,41 278,46 241,28
I did made the table above look good in my post and it looks good in the edit view, it just screws up when i read it on the board, go figure.
b) measured kW at wheels
c) corrected kW at engine
d) Torque in Nm(forget feet/square what ever .. )
P.S. does anyone of you guys knows the production numbers for 155Q4's in any country? I got the ones for the netherlands.(35 7+7+10+8+3 1992 till 1996 with 4 to 8 widebodymodels. 4 are wb for sure 4 i am not sure of the rest is the original shape.)
1500 is not the total number of Q4's worldwide. It is the numbers of Q4's that had to be fitted with a waterspray system to make it legal for alfa to race them with watersprayers fitted.
Mine doesn't have the wire-ing present so it was build after the serie of 1500 obvious.
I know there where 2290 Q4's build from 1992 to 1994. I do not have the total number. (4511 V6's in the same period.)
The total could be close to 4000? Maybe a little optimistic.(or pessimistic in terms of rarety of my car ) So lets keep it between 3000 and 4000 until somebody can give us some nice data.
Dragracing isn't really the most noble thing you can do with your Alfa. My excuse is that my one and only try for the 1/8 mile happend when I was invited for a trackday with the Sabb Turbo Club, the Volvo Performance (?) Club and the Opel GSI club ... what a combination ....
So, you guys think 9.59 is good? I don't know, but Honda S2000 and Audi S3 that made several tries needed another half a second. And I have to confess I made a start that I never thought was possible with the Q4. Perhaps more luck than skill and performance?
So, to your extraordinary performance figures Jan. It surprises me they get 18% transmission losses. Normally you count with 10%. Then it surprises me even more that you get so extremely good performance with the pre-cat mounted. My Q4 turned into a new car (almost) when I bought it a new full flow exhaust system without pre-cat, but with the other two cats. Another thing that puzzles me is the fuel pressure. Doesn't Squadra use standrad fuel pressure of 2.5 bar?
I saw a plot some weeks ago on the evoforum where a guy with an Evo1 and Evocar's chip had measured his car. According to that measurement it shold produce 269 hp and 410 Nm compared to the promised 260 hp and 393 Nm. But don't forget it is a car with a BIG turbo, much better intercooler and a with chip that runs on 3 bar fuel pressure.
Have you showed the plots for Stephan Lenoir at Squadra?
I mailed all the data to stephan. And he wanted to visit the test dyno. It is actualy the same one as he used to program his chip. He would contact me if he found anything, still haven't heard a thing though.
Transmission losses were set at 22% that means 3 procent more than your settings. But they apear to be accurate. (fwd is usualy accounted for with 15% and we do have a lot more drivetrain parts moving about.)
Is your Q4 roadlegal with the 2 cats instead of 3? I did hear sometime the first one only works when the engine is cold. Not sure if it is true though.
jajob, when you say transmission losses were set at 22% does that mean they were tested and found to be that much, or the tested said that was what they should be.
Not wishing to query the rolling road or anything, but I think the figures are a little optomistic, With basically just a free flow exhaust from the kats back, new air filter and chip, I think 240bhp is the best you could expect, unless of course the chip is letting the engine run huge amounts of boost.
The evocars chip needs the fuel pressure set to 3 bar to cope with the extra boost, i'd worry about any chip that ups the boost and doesn't need the fuel pressure changing.
The Q4 have never been officially imported to Sweden and at the yearly MOT (?) the emissions are meassured with hot engine (of course). Technically I suppose I can get in trouble with no pre-cat, but in reality - No. The pre-cat starts working almost immedatelly as it has low mass and is placed close to the turbo, but this arrangement even worsen the pressure loss. The exhaust system builder coinsdered the alfa pre-cat to be one of the smallest =worst on the market