Fishy?

Author
Discussion

CJN

Original Poster:

230 posts

275 months

Thursday 13th September 2001
quotequote all
I''ve just seen an advert for a V-SAM ECU chip that will give a claimed 4-6 BHP. There are also graphs on Brooke Kensington website. Am I better off buying 100 portions of the potato variety with fish from my local or should I put one in my Elise?? CJ

Rik A

51 posts

275 months

Thursday 13th September 2001
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As usual, the answer is "maybe". OK, here's how it works. The chip controls the amount of fuel and the spark timing. More fuel gets you nothing but worse fuel economy since the standard chip is already programmed to the optimum. Earlier spark gives more power, until detonation ('pinking') sets in. To account for unavoidable differences between one engine and another, spark timing is usually set about 3 degrees 'safe'. So if the chip just gives a more advanced spark, you might get another 2 Hp or so. The other 1-2 Hp come from engine to engine and test to test variability. No two tests, even on the SAME engine, give EXACTLY the same result. 1 Hp is less than 1%! What many chips do is to cheat. you get retarded spark at low revs, LOSING some low down torque. As the revs rise the spark timing is switched back to optimum, so the power comes in with bang. I have see professional test drivers fooled by this. Cars that felt 'better' with the cheat were measured 1s slower 0-60! ...Rik

smeagol

1,947 posts

286 months

Friday 14th September 2001
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There are lots of better and more cost effective ways of tuning. A "superchip" is usually not worth the money on its own. With the Elise, best tuning is to change the exhaust and air intake (filter). By improving the breathing of the car you increase its performance for little cost. More expensive but again good improvement is to buy a tuning upgrade (135 upgrade etc). These alter the cams and various other gubbins. Some of them also have a remapped chip included.