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Location:
Perth,western australia
Registered:
December 2003
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estimate HP??
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Wed, 30 June 2004 04:46
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what is a good way to estimate HP on a modded engine??
couldnt find anything in a search on 2t/3t hybird for estimated HP,but im also looking for some kind formula that i could apply to any motor .
cheers,
Dom
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: estimate HP??
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Wed, 30 June 2004 04:48
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Run a quarter mile, weigh the car, plug the numbers into one of the online calculators and you'll be within 25%.
Another good way is to put the engine on an engine dyno.
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Registered:
November 2002
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Location:
Potts Point, Sydney
Registered:
October 2003
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Re: estimate HP??
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Wed, 30 June 2004 07:48
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If you know your kW, multiply it by 1.34 and you get the HP. If you know your HP, the divide it by 1.34, and you get your kW 
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Location:
Perth,western australia
Registered:
December 2003
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Re: estimate HP??
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Wed, 30 June 2004 10:27
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mmm.
ok here goes.
im rebuilding teh block on 2tgeu and was gonn a stick in a 3t crank,some bigger injectors etc.
i got asked what hp it would put out.was wondering if it could be guessed.
not to fussed tho.
cheers guys
Dom
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Location:
Vancouver
Registered:
June 2004
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Re: estimate HP??
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Wed, 30 June 2004 14:52
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estimate HP output this way...
(1E-05) x (rpm for HP peak) x (pressure ratio) x (cc displacement) x (your chosen fudge factor, or "HP indexer") = approx HP target
let's say a 1800cc, running 6000rpm peak HP, and 15psi...
.00001 x 6000 x 2 x 1800 x 1 = 216HP
If you are trying to figure out a N/A motor, the combustion efficiency goes up a bit due to the greater expansion ratio of higher compression, but the turbo pressure ratio disappears...
let's say a 2000cc, running a HP peak @ 7000, no turbo...
.00001 x 7000 x 1 x 2000 x 1.25 = 175HP
Make any sense? It's not exactly a scientific report, or anything quantified to measure your motor by, but it's a helpful way to estimate your anticipated output if you are honest about a few things...
(if you want dreamy numbers, put in a dreamy "HP indexer" number, but generally, turbo motors will be around 1 - 1.05, and N/A motors will be around 1.15 - 1.30 depending on compression ratio and port flow capability)
Cheers
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Location:
Perth,western australia
Registered:
December 2003
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Re: estimate HP??
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Wed, 30 June 2004 16:46
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sweet.
just what iw as looking for.
cheers mate.
Dom
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Location:
Brisbane
Registered:
May 2002
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Re: estimate HP??
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Wed, 30 June 2004 22:58
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2T-GEU is rated at about 120hp from the factory (from memory). I reckon the 3T crank will be good for another 10hp, so my guesstimate would be 130hp. If you want anything more accurate than that, you'll have to chuck it on a dyno.
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Location:
Melbourne
Registered:
May 2002
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Re: estimate HP??
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Thu, 01 July 2004 00:42
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I have a 1.8 eight valve twin cam in my rally car. It has a knife edged crank, 3sgte rods, forgies, 11:1 comp, 5 angle seats, custom stainless valves, billet cams, quad throttles and after market management. Fair to say, that there has been no stone left unturned in my quest for hp. On a chassis dyno it made 105 kw at the wheels at 7200 rpm. You must remember that this engine cost me more that I care to think about, it is a race only motor, so yours will not make this kind of power.
Short of adding a dry sump I cannot see any more power being made. So from this point you could work backwards to get a figure for your engine.
After mucking around with 2tg's for a while, I will through in my two cents worth and say, with a good set of cams, multi throttle, a 3tg would be in the region of 165 hp at the crank. Plenty for the street.
Good luck.
Mal
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