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And on to the next chapter we go... I think this will def help get hopefully 50whp and 8000 rpm on a 15WhiteSi's FG4, my only question is are you going to pursue the COMP cams or wait for 4piston to release theirs?
I'm not sure yet. Once I get all the pieces together and decide which way i really wanna go with, i'll know more then.
 

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He’s going to need an oil pump upgrade for that kind of rpm to last.
If keeping it at a 8000-8200 limiter, I personally would debate that because the oil pump design is largely the same as the 8th gens which stock also revved that high, I’ve also seen a lot of turbo guys rev to 8k no problem frequently. Would it help with a bit of power and top end oil pressure? Absolutely and I would if I had the money, but is it necessary? Nope. Only if one were to go above 8500 would it really be considered a risk. Just in mind the balance shafts help with reliability also in the sense of canceling out the 2nd order vibrations and that the type-s pump is one of the hardest mods to do on this car.
 

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If keeping it at a 8000-8200 limiter, I personally would debate that because the oil pump design is largely the same as the 8th gens which stock also revved that high, I’ve also seen a lot of turbo guys rev to 8k no problem frequently. Would it help with a bit of power and top end oil pressure? Absolutely and I would if I had the money, but is it necessary? Nope. Only if one were to go above 8500 would it really be considered a risk. Just in mind the balance shafts help with reliability also in the sense of canceling out the 2nd order vibrations and that the type-s pump is one of the hardest mods to do on this car.
Here's my issue your statement, and I am by no means saying we have to agree on things.

Both he and I have invested a boatload of cash on the car, and to not do this $400 safety net is sorta silly.

I disagree - It's actually a very easy mod, considering you're already taking the head off, and likely taking the engine out. The PRL and K-Power kits, really make it a "bolt on" affair.

It can be a tight squeeze if this is all you're doing, while the engine is still in the car.
 

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Lighter pistons would be what I'd go for also. The piston speed at that RPM is getting pretty ridiculous.
 

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Lighter pistons would be what I'd go for also. The piston speed at that RPM is getting pretty ridiculous.
yep, and there might be no power to gain up there. I lost 30HP from 8200 to 8500RPM at the dyno. So we dialed it back. To be honest after 8K it start to level off, limiting factors of the head flow, so I don't abuse my car up in that range too often. There's no need.

here's some good info I found on Piston Speed on Honda-Tech

Some more numbers, this time in feet per second @ 8,500 rpms:
B16 - 4,317 fps
F20c - 4,685 fps
K20 - 4,797 fps
B18c - 4,864 fps
B18a/b - 4,963 fps
H22 - 5,059 fps
H23 - 5,299 fps
K24 - 5,522 fps

really makes you wonder.
 

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That's amazing that the block and head are able to withstand that. That's dumb fast. Over a mile a second of travel?? That's just wild.
 

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This puts piston speed/RPM into perspective. I was there when they did this lol. It was nuts. For those who don't know the GM lingo, an LS7 is a 7.0 Liter/427 Cubic Inch Chevrolet "Small Block".

You should have seen how excited Billy was dancing through the halls after this. Billy is the one who put these lobes together for the K24z7 regrinds for me.

 

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Here's my issue your statement, and I am by no means saying we have to agree on things.

Both he and I have invested a boatload of cash on the car, and to not do this $400 safety net is sorta silly.

I disagree - It's actually a very easy mod, considering you're already taking the head off, and likely taking the engine out. The PRL and K-Power kits, really make it a "bolt on" affair.

It can be a tight squeeze if this is all you're doing, while the engine is still in the car.
I never made it about who agrees with who lol but it’s circumstantial of course and what you said makes sense and I would be on that boat myself but I was just coming from a different perspective such as certain people who it may not be much of a concern for lack of budget reasons, lack of care, the work/labor, etc., so I didn’t didn’t or don’t mean to come off as disrespectful.

But in regarding the piston speeds, an idea that I had recently I wish to share to everyone, that I think is interesting but strange, is using a 93 mm crank with an 88mm bore to, rev all the way 8k with oem reliability. My reasoning is this here, a 93mm stroke @8k is 4,800fps which is modest and can be pushed to 5000 at 8.2k. The 88mm bore is now to make up for (almost) all the displacement (ALMOST, bc it will be 2.311 cc vs the oem 2.354cc, and you unless you are sleeving, 88 is already risky so you are quite bore limited). And this will, (in theory) make the engine more top end happy, still with torque but without beating the crap out of it in the long run. This of course is more costly and not for the average enthusiast/weekend projecter,but hey, any thoughts?
 

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Swapping the head does not equal taking the engine out at all in my world... Swapping heads is like swapping intake manifolds really. Just clean the surfaces, new MLS head gasket and go.
 

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yep, and there might be no power to gain up there. I lost 30HP from 8200 to 8500RPM at the dyno. So we dialed it back. To be honest after 8K it start to level off, limiting factors of the head flow, so I don't abuse my car up in that range too often. There's no need.

here's some good info I found on Piston Speed on Honda-Tech

Some more numbers, this time in feet per second @ 8,500 rpms:
B16 - 4,317 fps
F20c - 4,685 fps
K20 - 4,797 fps
B18c - 4,864 fps
B18a/b - 4,963 fps
H22 - 5,059 fps
H23 - 5,299 fps
K24 - 5,522 fps

really makes you wonder.
I would at least try to put some longer rods and customs pistons that relocate the pin higher to improve the Rod Ratio a bit... Piston speeds would still be high but it would decrease stress a bit..

Marko!
 
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Longer rods would definitely help along with lighter pistons. Longer rod Chevy small blocks can pick up torque with them too, if I remember correctly
 
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