Jamie
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Registered: 1st Apr 02
Location: Aberdeen
User status: Offline
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What type of engine is it/car it from? 
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
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Apparently it's a volvo
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Greg_M
Member
Registered: 2nd Sep 03
Location: Grantham, Lincolnshire
User status: Offline
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ive said it before and ill say it again, looks like a vtec to me/
but others claim its a holden engine
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Teddy
Member
Registered: 19th Jul 04
Location: Northampton Drives: VW Bora 1.9TDi pd130
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Adam_B
Member
Registered: 13th Dec 00
Location: Lancashire
User status: Offline
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its not a volvo engine.
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Kerry
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Registered: 5th Oct 01
Location: Norwich
User status: Offline
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quote:
Originally posted by J-Me
What type of engine is it/car it from?
a very hot one 
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AK
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Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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how many 6 clyinder vtec engines do you know of?
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Filby1
Member
Registered: 12th Dec 03
Location: Brighouse
User status: Offline
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Have you not seen F1 Engines on the test bed man they Glow
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Ditch
Member
Registered: 29th Nov 02
Location: St Albans Drives: JDM Celica GT4 WRC
User status: Offline
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quote:
Originally posted by Adam Kindness
how many 6 clyinder vtec engines do you know of?
1
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Ditch
Member
Registered: 29th Nov 02
Location: St Albans Drives: JDM Celica GT4 WRC
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eitherway, the NSX lump it is not.... unless someone turbo'd one!! 
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AK
Member
Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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NSX is V... not straight...
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leeshez
Member
Registered: 3rd May 01
Location: Great Harwood, Lancashire
User status: Offline
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
User status: Offline
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Does vtec mean anything?
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
User status: Offline
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Or is it just like gsi etc. just a 'tag'
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mwg
Member
Registered: 19th Feb 04
Location: South Lakes
User status: Offline
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quote:
Originally posted by Carr
Or is it just like gsi etc. just a 'tag'
vtec is something to do with the way the engine works at a certain revs but I dont know how it works etc.
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AK
Member
Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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Variable valve Timing and lift Electronic Control
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willay
Moderator
Organiser: South East, National Events
Premium Member
Registered: 10th Nov 02
Location: Roydon, Essex
User status: Offline
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edit: beaten by adam
[Edited on 17-06-2005 by willay]
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
User status: Offline
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quote:
Originally posted by Adam Kindness
Variable valve Timing and lift Electronic Control
Cheers
what does it do?
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AK
Member
Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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the cam has multiple lobes...
normal, and high lift (like having a sep high lify cam)
Whn engine hits 'vtec' point it shifts the cam to run on 2nd higher lift lobes
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
User status: Offline
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Oh right. Youlearn something new everyday 
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AK
Member
Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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Introduction to VTEC
In the regular four-stroke automobile engine, the intake and exhaust valves are actuated by lobes on a camshaft. The shape of the lobes' determine both the timing and the lift of each valve. Timing refers to when a valve is opened or closed with respect to the combustion cycle. Lift refers to how much the valve is opened. Due to the behavior of the gases (air and fuel mixture) before and after combustion, which have physical limitations on their flow, as well as their interaction with the ignition spark, the optimal valve timing and lift settings under low RPM engine operations are very different from those under high RPM. Optimal low RPM valve timing and lift settings would result in insufficient fuel and air at high RPMs, thus greatly limiting engine power output. Conversely, optimal high RPM valve timing and lift settings would result in very rough low RPM operation and difficult idling. The ideal engine would have fully variable valve timing and lift, in which the valves would always open at exactly the right point and lift high enough for the engine speed in use.
In practice, such a perfectly adjustable timing and lift system is complex and expensive to implement and is therefore found only in costly experimental and limited production engines. The vast majority of modern automobile engines operate with a fixed camshaft profile that represents a compromise between low RPM smoothness and high RPM power output. And since the average automobile engine spend most of its time running in the low RPM region, there is typically more emphasis on low RPM smoothness at the expense of high RPM output. Performance-tuned engines have cam profiles that are optimised more towards high RPM operation, where the greatest power can be obtained, but this means that low speed operation is compromised. Anyone who has heard a racing car or a highly-tuned hot rod sitting at idle will note that the engine sounds like it is barely capable of running at that speed.
[edit]
DOHC VTEC
Honda's VTEC system is a simple and fairly elegant method of endowing the engine with multiple camshaft profiles optimized for low and high RPM operations. Instead of only one cam lobe actuating each valve, there are two - one optimised for low RPM smoothness and one to maximize high RPM power output. Switching between the two cam lobes is controlled by the engine's management computer. As engine RPM increases, a locking pin is pushed by oil pressure to bind the high RPM cam follower for operation. From this point on, the valve opens and closes according to the high-speed profile, which opens the valve further and for a longer time. The VTEC system was originally introduced as a DOHC system in the 1989 Honda Integra sold in Japan, which used a 160HP variant of the B16A engine. The US market saw the first VTEC system with the introduction of the 1990 Acura NSX, which used a DOHC V6. The DOHC VTEC system has high and low RPM cam lobe profiles on both the intake and exhaust valve camshafts. This resulted in the most power gain at high RPMs and DOHC VTEC engines were thus used in the highest performance Honda automobiles. In contrast to the SOHC implementation which switches between cam profiles seamlessly, when the DOHC version switches cams there is a definite change in the engine note.
[edit]
SOHC VTEC
As popularity and marketing value of the VTEC system grew, Honda applied the system to SOHC engines, which shares a common camshaft for both intake and exhaust valves. The trade-off is that SOHC engines only benefit from the VTEC mechanism on the intake valves while the exhaust valves are still actuated by a single cam profile.
[edit]
SOHC VTEC-E
Honda's next version of VTEC, VTEC-E, was used in a slightly different way; instead of optimising performance at high RPMs, it was used to increase efficiency at low RPMs. At low RPMs, only one of the two intake valves is allowed to open, increasing the fuel/air mixture's swirl in the cylinder and thus allowing a very lean mixture to be used. As the engine's speed increases, both valves are needed to supply sufficient mixture, and thus a sliding pin as in the regular VTEC is used to connect both valves together and start the second one moving too.
[edit]
3-Stage VTEC
Honda also introduced a 3-stage VTEC system in select markets, which combines the features of both DOHC VTEC and SOHC VTEC-E. At low speeds, only one intake valve is used. At medium speeds, two are used. At high speeds, the engine switches to a high-speed cam profile as in regular VTEC. Thus, both low-speed economy and high-speed efficiency and power are improved.
[edit]
i-VTEC
As successful as the VTEC system has been, one of the key arguments against it in comparison to competing systems is that it had only two profiles for timing and lift. i-VTEC answers the critics by introducing continuously variable timing. The valve lift is still a 2-stage setup as before, but the camshaft is now rotated via hydraulic control to advance or retard valve timing. The effect is further optimization of torque output, especially at low RPMs.
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Carr
Member
Registered: 1st Oct 04
Location: Leicestershire (Home) Ambleside, Lakes (Uni)
User status: Offline
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Cheers Adam, interesting read that
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danny-corsa
Member
Registered: 15th Mar 05
Location: Warwickshire Drives: Astra GSi 16v
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skyline???
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AK
Member
Registered: 5th Jul 00
Location: Aberdeen City
User status: Offline
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its not a skyline engine.... doesnt look like one that is...
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danny-corsa
Member
Registered: 15th Mar 05
Location: Warwickshire Drives: Astra GSi 16v
User status: Offline
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just quessing 
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