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Hello everyone
I would like to know the highest hp for the exige s v6 stock engine can take before the piston and connecting rod will give up
Because I'm planning to tune it up to 480bhp
I'm assuming that it can take up to 460bhp like the komotec but not sure if it can take more
 

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boxerman
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406 Posts
Hello everyone
I would like to know the highest hp for the exige s v6 stock engine can take before the piston and connecting rod will give up
Because I'm planning to tune it up to 480bhp
I'm assuming that it can take up to 460bhp like the komotec but not sure if it can take more

The issue with the stock rods I understand relates to engine timing, as even slight imperceptable detonation will blow the rods. The stock setup is not intercooled and the supercharger is already at its thermal limit, so as heat builds the computer pulls timing and makes the mixture rich to limit the possibility of detonation, of course like all manufactuers lotus choose the most conservative safe timing to save on potential warranty.

If you want lots of power look at the big blower(tvs 1900) and intercooled setup from harrop in australia. The big blower and intercooling can take an otherwise stock car to close to 500hp, apparently safetly. Whether your gearbox will survive long at that power level is another story and depedant on use cycle because the gearbox while strong also has heat issues. However once youre chasing 500hp and the big blower, imo might as well be safe change the rods and go for 600hp which that setup will do. figure on not less than $30k, plus whatver the gearbox needs.

All of this also depends on use cycle. On track you're using 90-100% of the motors power all the time. On street its 20-60% of power with maybe occasional short 100% bursts. On street the gearbox is fine and a modded setup wont run too badly into heat issues because mostly youre not dipping into full power long enough. In any modded setup they use diffrent tunes with more timing, so the margin for error is reduced.

On my car I have gone for no cats, long tube headers(which do add hp) and a moderate tune, I also only run race gas as a precaution. My Hp will hover around 400 or so, but it also wont fade. For track I think this is more than enough, and short ratios would be my next step rather than more power. This is the setup that the guys who race these cars in nevada use, hot and dry is the hardest enviroment, so what lives there, lives everywhere. Stock I think maybe these cars put out 360 hp but as soon as you get to heat soak after a few laps you're looking at 300-320 due to timing and rich fuel.

Any mod that spins the stock supercharger faster though a pulley change will only temporarily increase power due to supercharger inefficiency and resulatnt heat, intercooling helps mitigate this, but youll still workign against the 1320 limitations.

You might also considder the shorter gear ratios, that will really wake the car up, because 5th and 6th are pretty tall.

I would start with this question, what is your use cycle for the car? If its track thats one consideration, better to loose weight(headers, gear ratios) than add it(intercooler and big blower). If youre runnign balls out on the open road thats another view, and a 500hp big blower intercooled setup makes sense and will live. If its a street car with occasional blasts you can get away with less engineering, ie keepign the stock blower and intercooling.

Its all fun to think about, but how you use the car, should be your starting consideration for what is appropriate.
 

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Sold my Exige S
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What boxerman said about your intended use matters most. Strictly street use and you could survive on stock internals.

The rods are the weakest link in the 2gr - they're not forged like the 2zz.
 

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ive had a few of these apart & have a stock supercharged one in my race Exige. i have 350HP at wheels and would not attempt much more without significant internal and external upgrades
 
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