Not really. There is only so much cylinder height. and ideally for the same
displacement/bore/stroke, they should start and stop at the same spot in the
cylinder, near the top to get the best squish........
Daryl
----- Original Message -----
From: "Eddie" <eddietude@socal.rr.com>
Subject: Re: [Roadsters] long rod (r16) stroker
>I thought the longer rod also pushed the piston farther "up" the cylinder
>wall, thus compressing the gas MORE... and that's where the power gain came
>from...
>
> Isn't that also the case?
>
> Eddie
> Gordon Glasgow wrote:
>> The guys at Circle Track magazine did a pretty thorough test of this a
>> few
>> years ago. Basically a longer rod will broaden the power band because the
>> piston sits at TDC longer and the angularity of rod and crank improves
>> the
>> leverage slightly. In a 350 ci Chevy at 9000 rpm, it makes a difference,
>> but
>> you probably won't be able to tell the difference on a street motor.
>>
>> Basic truths for the technically-inclined:
>>
>> With a longer rod, the piston will remain near TDC and BDC longer. At TDC
>> on
>> the Power stroke, this allows cylinder pressures to build a bit higher.
>>
>> Since the piston has to traverse the whole cylinder during each cycle,
>> and
>> since the maximum piston speed at the middle of the cycle will be the
>> same
>> regardless of rod length, this means that piston ACCELERATION will be
>> somewhat greater with a longer rod. Again, this may be a factor at 9000
>> rpm
>> with super-light pistons, but not in a street motor.
>>
>> A longer rod will also weigh more than a shorter rod, while the piston
>> weight will change very little (if at all). This may reduce the ability
>> of
>> the engine to rev, partly offsetting the gains from the first factor.
>>
>> Gordon Glasgow
>>
>> -----Original Message-----
>> From: datsun-roadsters-bounces@autox.team.net
>> [mailto:datsun-roadsters-bounces@autox.team.net] On Behalf Of Daryl Smith
>> Sent: Wednesday, April 08, 2009 4:21 PM
>> To: Tim Waltz; datsun-roadsters@autox.team.net
>> Subject: Re: [Roadsters] long rod (r16) stroker
>>
>> I keep hearing about it, but haven't heard any definitive information on
>> the
>>
>> correct pistons to use.
>> The rod angles will be slightly smaller, but from my reading this will
>> minimally affect power and torque.
>> The 280/300z pistons may however be cheaper than U20 pistons which may
>> make it a more attractive option to some.......
>> Read this thread for a detailed discussion:
>> http://www.gofastnews.com/board/engine-technology/85-rod-ratio-vers-eng-acce
>> leration.html
>>
>> Daryl
>>
>>
>> From: "Tim Waltz" <printner@att.net>
>>
>>
>>> Another stroker option I've heard of is using the longer (R16) rods, and
>>> later Nissan (280Z, 300Z?) pistons.
>>>
>>> Has anyone ever heard of this, done this, or have any insight on this?
>>> I've heard it has more torque and lower rod angles. Sounds like a great
>>> option, but I need more info.
>>>
>>> TIA
>>>
>>> Tim
>>> 67.5 1600 waiting to be stroked
>>> (that doesn't sound right)
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