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The stroker will change the geometry in the motor leading to excess angulation and wear. With that said, there aren't too many (if any) stroker VR38 failures documented.

Sunny Bryant and Linney stroker cranks are the most popular.
 

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Rod/stroke ratio is important for engine longevity and goes hand in hand with the internal rotational mass and max/mean piston speeds.

That being said, pistons and r/s ratios aren't that big deal with low hp engines as the K24 has a r/s of 1.54 but they last forever. Boost it to 800whp and it won't last. That's why many of the highest hp cars destroke their engines and trow in longer rods. It decreases piston speeds and increases the r/s ratio. It's important to understand mean and max piston speeds too. I am a firm believer that max piston speeds should never exceed 5kfpm.

My LR2.4 in the Evo only lasted about 22k miles before the side loading scuffed up the cylinder walls bad enough for a rebuild. My r/s ratio was a 1.56. Better than the K24 I mentioned above but my max piston speeds were around 5600-5800 depending on where I needed to shift. Max piston speeds are relative to crank stroke, but longer rods decrease mean piston speed.

I've had many debates on this topic for years. But to give you an idea, F1 engine piston speeds don't go over 4800fpm so it's a good rule of thumb that we do the same. That being said, I would feel safe running a 4.1L 94.4mm crank to 8000rpms tops. The 3.8L r/s ratio is an amazing 1.87 and even the 4.1L still has a great r/s ratio of 1.72. I think anything higher that a 1.7:1 r/s is preferred and the 4.1L fits in that category as well, so I would say it will probably be just as reliable as a 3.8L under normal wear/tear. Fyi, the high r/s ratio doesn't only decrease side loading of the cylinder walls, it also means the Pistons stay at TDC longer allowing for better cylinder scavaging.

Sorry if this is all over the place... typing while driving isn't the easiest. Lol hope this helps.

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I have 4.0 L Linney crankshaft stroker and revs to 8k all the time (only 1.5 week since build lol). Downside for now is too much torque for my 7 plate clutch!
 

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I have 4.0 L Linney crankshaft stroker and revs to 8k all the time (only 1.5 week since build lol). Downside for now is too much torque for my 7 plate clutch!
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On the 4.0L are you running a 165mm rod and 92mm crank? I've thought about running a high compression 4.0L with a 31.3mm compression height piston with a 166mm rod or if I really wanted to get crazy I'd go with a 167mm rod and a piston CH of 30.3mm. The later of the two is almost the best of both worlds with more displacement and could rev to 8500. I'd patent it as the Long Rod 4.0L. Although the money your have to pay to get this wouldn't be worth the minimal r/s advatage. Lol

English Racing built a Long Rod 3.8L which (I'm assuming) was probably built with a 31.3mm CH piston 10:1 cr (they are the 4.1L pistons) paired with a custom R&R 168mm rod. They may have went crazy and did a 30.3 CH piston as they like to test limits a lot - which is a great thing. The general rule of thumb I've been taught is never go below a 30.0mm ch piston on a turbo car.

Speaking of tq... this is why I have a built high compressiom 3.8L. I may go to 4.0L in the future but no anything larger. Enjoy your motor man ;)
 

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Yes linneytuning 92.4 mm crankshaft. Not sure other stuff except custom JE pistons and linneytuning rods.

Sent from my SM-G900V using GT-R Life mobile app

On the 4.0L are you running a 165mm rod and 92mm crank? I've thought about running a high compression 4.0L with a 31.3mm compression height piston with a 166mm rod or if I really wanted to get crazy I'd go with a 167mm rod and a piston CH of 30.3mm. The later of the two is almost the best of both worlds with more displacement and could rev to 8500. I'd patent it as the Long Rod 4.0L. Although the money your have to pay to get this wouldn't be worth the minimal r/s advatage. Lol

English Racing built a Long Rod 3.8L which (I'm assuming) was probably built with a 31.3mm CH piston 10:1 cr (they are the 4.1L pistons) paired with a custom R&R 168mm rod. They may have went crazy and did a 30.3 CH piston as they like to test limits a lot - which is a great thing. The general rule of thumb I've been taught is never go below a 30.0mm ch piston on a turbo car.

Speaking of tq... this is why I have a built high compressiom 3.8L. I may go to 4.0L in the future but no anything larger. Enjoy your motor man ;)
 

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I don't like HKS parts. Usually expensive garbage. However, I do like the Legamax exhaust but mine fell apart and they wouldn't warranty their garbage Flux welds that cracked. So I'll never buy their parts again.

I definitely wouldn't get the HKS stroker kit. I personally don't like the 95.5 crank. I would look at a good 4.0 kit like Linney's or get ETS 4.1L.

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