January 25, 2013, 5:26 am
Tuners/ Mappers/ performance parts suppliers often exaggerate the figures, it can be a mistake to choose one product over another because its manufacturer/ supplier claims a few more Hp than another.
Often its the more "respected"/ "established" tuner that claims the smaller Hp gains, and the less well known tuner claims the biggest gains -
"claims" is the word -
Different dynos read and work differently, 1 may read higher, one lower, only the power from the wheels is measured, the crank power is "estimated" (guessed) dyno figures are "corrected" due to temprature etc, a typical car producing 125Hp at the wheels, suddenly becomes 180Hp at the crank, so where did the lost 55Hp go? did the gearbox absorb it? no, it would get too hot, gearboxes are not as inefficient as that, (thats more than 40% of the power) might as well say you have a 1000Hp car, but only 125Hp makes it to the wheels because only the power that makes it to the cars' wheels is important - it makes no difference what the "crank" Hp is.
The shape of the power and torque curves are important, a car with a wide, progressive power and torque curve may be quicker than an identical car (measured in the same way on the same dyno) that has a higher "peak" power over a narrower range and lets not forget torque
A famous quote :-
"Power (figures) sell cars, torque wins races"
Power figures sell remaps, tuning boxes, performance parts, too, it seems, but you've got to take them with a big "pinch of salt"
The Superchips Blufin is a remap just like a "custom" remap - Superchips can upload your original map and modify it to your modifications/ requirements, some "custom" remaps are just generic maps bought off the net, often all they dio is turn the fuel pressure up this is whats called a "tuning box" remap.
A dyno run with "before" and "after" charts/ plots with a road test and a custom remap (a proper "live" remap is not always possible on all cars/ cpus/ ecus), specifically set up for a particular car and its modifications (after the modifications are fitted), buy an established reputable remapper should ultimately give the best results, (but can be expensive, and may not produce much more power (if any) than a Blufin or "generic" remap)
It is often said that tuning boxes are simply a resistor that fools the ECU to squirt more fuel into the engine, and that the more expensive ones are just resistors too in a nicer box with the correct connectors.
Tuning boxes differ in price and quality - from a £7 box with a resistor (theyve got them now with pictures showing the resistor that looks like a silicone chip!) to microproccesor digital adjustable - multi-map boxes costing £400- £500
I ran one for years - it worked brilliantly - 100% reliable - it was a DT-UK one, it was adjustable and turned up for maximum power, ive recently fitted a Superchips Bluefin, initially with the Bluefin there was more top-snd power but i lost bottom end power realative to the tuning box - Superchips supplied a revised map for my modified car (120psi electronic boost controller, CAIS, gas- flowed airbox, resonator bypass, drag racing FMIC with waterspray, heatwrapped decat, straight-through exhaust, - i said i wanted it derestricted, in the lower gears and not torque- limited as i ran a strengthened trans (Solid SMF, carbon kevlar clutch, heavy-duty backplate 33% more clamping force) and with the total EGR delete and straight-through exhaust a little smoke wont harm it (carbon build up not a problem) but not more smoke than was nessesary for max power/ torque
I installed the rvised map on the car and the bottom end power is only slightly less than the tuning pox alone (at about 1k) but above that it pulls better, and the top end is a lot better, there is a little bit of smoke at startup, and initially on accelerating hard but overall not bad, i will try testing the tuning box AND the remap, but it looks like i wont need the tuning box as it probably wont make any difference with the Superchips map installed
The car has been lightened 155Kgs (so far) and the AC pump/ pulley removed and electric waterpump fitted (less rotating mass/ losses) i got the revised map from Superchips recently, with the bad weather ive not really had a chance to test it properly I fitted a fresh air filter , and timed a 4.86sec 50-70mph in top, im very pleased with that (previously it was 5.7ish) - the car is quick, and i still get 40 MPG
The car is probably one of the most heavily (performance) modified Mk3 diesels around,(not the usual decat, ss exhaust + bigger FMIC) but Superchips produced a map that was significantly better than the DTUK box, (even turned up) , in direct comparison (i time the 0-60etc) or the original "generic" Superchips map i might try a costom remap in the future - it would be interesting to see if i could squeeze a bit more power out of it (not that im obsessed or anything!)