2021FLTRK
Well-Known Member
Never mind
Last edited:
@thecatsfanWiki says that Loveland is about 4800 ft elevation, that's gonna be a downer.
Doing the math;
If your 318 is an LA with a true deck height of 9.600, those piston-tops are still gonna be .012 in the holes.
This, at 020 over, is 2.4cc, add
the dome/ eyebrows, -6
the for the heads 72 and
for 039 FelPros 8.6
this totals 77cc, and so your 318 comes in at about
(658.9+77)/77=9.56 Scr. The quench is gonna be too tight
So the bad news is that even with the stock 318 cam (Ica of 48*) at 9.56 Scr, she's only predicted to put out ~150psi.
By the time you get to two sizes bigger, a 262/266/110 cam, (Ica of 60*) the pressure is down to ~134psi, so, at 4800ft, about as powerful as the stock 318 is, at sealevel, until the rpm gets up to around 3500. aaaand yur still buying a convertor and probably gears.
IMO with that 318, at 4800ft, to run a 262 cam, the Scr is gonna need to get up to around 10.7, and that would be a total chamber volume of 67.9. And that's gonna take closed chamber heads, and pistons with no quench pads!
So, IMO, yur stuck doing one of three things
1) with your plan, a really small cam, milled pistons, and a convertor, or
2) as above but in addition; slightly bigger cam and gears
3) buying closed chamber heads and other flat-top 318 pistons, and maybe a convertor
4) buying a 360 short with Q-pads to slide under your open chamber heads, and running whatever convertor and gears you already have.
As to #4; Hint:
KB makes some nice KB-191 series Quench-pad pistons to work with the open chambers, to make a longblock with enough Scr to run just about any street cam you could think of.
4800ft is a bit of a downer.
Already have a machined crank and rods, as well as the heads. Had an entire rebuilt engine but the block was bad. Long story. Starting with a new block and this opportunity is sitting on the shelf at a reasonable price.or...... if the crank's not ground yet then consider a 4" stroker kit to put under the 360 heads. 390 cu in sounds better while you're doing it than 318 and it's all new too.
neil.
If your machinist isn't capable/willing to do the needed calculations and mock up, then skip these pistons and get something else.Already have a machined crank and rods, as well as the heads. Had an entire rebuilt engine but the block was bad. Long story. Starting with a new block and this opportunity is sitting on the shelf at a reasonable price.
Do not take advice of someone on the internet telling you a piston will or will not fit your engine build.
I understand your dilemma, but unfortunately there is just no easy yes/no answer to your question. Your EASY way out is just buy a cheap set of stock replacement pistons.Nobody asked for predictions. I literally asked for the opposite - actual experience from people who have these pistons.
Nobody can predict anything for certain, and I am not asking anyone to. In fact, I would prefer people don't try. But hearing other people's experiences is still valuable in determining whether the mock up is a worthy investment, or if I am better off going with a piston with a high probability of a good fit.
I don't have usable pistons right now. I have a block, crank, rods, heads, lifters, intake, etc. If I even want to mock up these pistons, I have to pay to bore the engine to get them in the hole for mock up. I am simply at a decision point - and actual experience of others could be helpful in deciding which way to go.
Everything on “the internets” is true.If I’m getting the drift of what you’re saying……… it’s like you’re implying some stuff on the “internets” may not be true and reliable info?
My vote is find a new machinist.If your machinist isn't capable/willing to do the needed calculations and mock up, then skip these pistons and get something else.
So you've called United Engine and Machine. Did you talk to Marco? He's the one you want to talk to.I have not once asked anyone for advice on running these pistons. I am asking if anyone has run them and how it went. It is a simple question out of curiosity. And I absolutely am not looking for anyone here to tell me they will work. If the piston manufacturer cannot even answer that question, trust me, I know nobody here can. But knowing what other people encountered with the same parts would still be good information as I wait for the block to get bored.
I have taken measurements. I have done the math. We will mock it up if the .020 bore works with this block.
That ^^^^ is great news. It’s the only way to know for sure. And when someone comes in here in a year and asks the same question you did, you’ll tell them exactly what all of us have told you. Mock it up and measure, then modify to fit. There are a lot of competent guys here, some have commented on this thread and given you good responses, and those responses were predicated by all the junk we’ve screwed together that didn’t work like the manufacturer said, or the book said, or someone else said, would work.I have taken measurements. I have done the math. We will mock it up if the .020 bore works with this block.
No, if someone comes in here and asks, "has anyone used KB399 pistons", my answer would be yes. If someone asks, have you used some other piston, I would not answer at all.
i just checked and you've been a member here since 2019. i'd have thought you'd be nicely 'thick skinned' by now, lol. it's needed sometimesWith all due respect, I don't need to be told what to understand. I understand perfectly that I asked a specific question and people who had no answer to the actual question chose to offer unsolicited advice I already know. I am not saying they are not intelligent and experienced in the subject at hand. I am saying everyone chose to tell me a bunch of information I never asked for.
If I could delete this thread I would. It has been a massive waste of time.
With all due respect, I don't need to be told what to understand. I understand perfectly that I asked a specific question and people who had no answer to the actual question chose to offer unsolicited advice I already know. I am not saying they are not intelligent and experienced in the subject at hand. I am saying everyone chose to tell me a bunch of information I never asked for.
If I could delete this thread I would. It has been a massive waste of time.
Tried being nice, now I’m done. Piss off.No, if someone comes in here and asks, "has anyone used KB399 pistons", my answer would be yes. If someone asks, have you used some other piston, I would not answer at all.
Just do like I did. Add him to the list. That way, you'll never see his posts again.Tried being nice, now I’m done. Piss off.