why use high duration cam?

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200sxBoY

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i wonder why everyone uses high duration /lift cams on their turbo engine (aka sr20det)

do they really get you guys more power ?
 
by theory no.. best turbo cam is a stock cam :p

that's precisely my opinion, so i wonder why people buy 280++ duration cam for their engine ... somehow some people don't care about dumping 20% of their fuel/air in the exhaust ?
running more overlap that a n/a engine would need lolz
 
Well I would put a set of stage 1 to eek out a few extra ponies out of my setup at the top end without having to all that headwork running aggresive cams require. It isin't necessary by any means and a pretty expensive way to make extra HP, I remember looking up pricing for a pair of Tomei PONCAM (street) and are sold as a pair for like $500+shipping yadayadayada. Like extra $500 could have been put on my turbo budget.
 
HKS 256 Cams are amazing for a few extra ponies and a high end kick for lightly modded SR's , Tomei poncams same idea,. ... 256 'ers are pretty much ideal cams without redoing the head. but internal work is always a plus,. it really depends on budget and what your goals are.

check it out with the ninja himself Okachan @ Yashio Factory
watch Drift Tengoku vol 8


*tu*
 
I would put the rolls of pennies down for Tomei because they do they're own in house R&D work. Mad props to them for their engineering skills! You pay for it, but you are definately getting something that is worth every penny.
 
i've seen a sr20@10psi gain 7-8whp on the top end and 10-13 whp in the mid range just by playing with cam timing with a stock cam

do you have any dyno graph w/ w/out the tomei or hks cams ?
 
I could maybe try and find some on Zilvia or freshalloy forums...those guys are hardcore on their tuning and share alot of what they know.
 
Plus de duration sans changer le lift peut faire perdre du torque a bas régime, mais rallonge la durée du torque à haut régime.

Plus de lift avec la meme duration, ne fait pas perdre de torque a bas régime, mais ce dernier ne durera pas aussi longtemps à haut régime.

On peut mettre des cams plus agressifs sur des voitures turbo, mais ce qu'il faut bien comprendre, c'est que c'est surtout l'overlap qui va faire la différence entre bien marcher pis marcher en sale. De plus, un cam d'intake qui reste ouvert trop longtemps ne serivra à rien, car si la chambre de combustion est pleine et que la valve est encore ouverte, ya pas plus d'air qui entre.

Le but d'un cam turbo est de faire rentrer le plus d'air possible sous pression dans la chambre de combustion. Donc théoriquement, un cam d'intake qui reste ouvert plus grand, plus longtemps permettera de faire ca. Sauf qu'il faut aussi que le cam d'exhaust soit capable de rester assez longtemp ouvert pour permettre aux gaz d'échappement d'évacuer la chambre, tout ca sans creer trop de lag pour rien.

Si ya trop d'overlap, à bas régime l'air poussé dans la chambre de combustion risque beaucoup plus de ressortir immédiatement par l'exhaust vu qu'elle est carrément poussée et non aspirée.

Et bien-sûr, il reste toujours le compromis à faire entre conduite de ville et performance...
 
beaucoup d'equipe roule des cam stock ou pratiquement stock (a quelque degre de duration de +) sur des moteur qui produise 2 fois plus que nos moteur de rue

je crois sincerement que des cams 270degree c'est totalement inutile . donc je voulais savoir si quelqu'un avait des dyno chart avant/apres avec des cams switcher (sur un moteur turbo)
 
like i said watch Drift Tengoku vol 8 OKACHAN does a dyno run before ( stock) and after with HKS 256 cams and on track with driver impression,. you can see a nice difference on the dyno chart

and he explains everything ( if you magically understand japanese) :bigup:
 
like i said watch Drift Tengoku vol 8 OKACHAN does a dyno run before ( stock) and after with HKS 256 cams and on track with driver impression,. you can see a nice difference on the dyno chart

and he explains everything ( if you magically understand japanese) :bigup:


do you understand japanese ?
 
no i magically don't. !!!


but this helps a lot,...


dictionary.jpg


:dunno: :bigup:


google search ?
 
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