Oops only 75.5
Oops only 75.5
.What's the difference between std and E58 ?
He was either way he just warned me about tuning and getting it correct or you can create your own issues. Some refused to build at all with them. My big issue is don't want to have to rebalance everything and have a crank that I could never use again. Read a few here and horror stories on confusion what harmonic balancer do I use now torque converter and plate and such. Just trying to take all the information in and weed out the BS and the real facts. HP is great but not at the sake of reliability is also the goal here.If your engine builder has problems with KB hyper pistons breaking, you need a different engine builder.
Right and they have some silicon in them I'm sure makes perfect sense. Just not what I need for my application right. I get the part of why I don't need to spend on forged for something I really don't need. I have a buddy has forged like yours he makes way more horsepower but he does not track the car and just drives it 15 years since the build 351 CJ as a 390 stroker around 550 HP. For sure reliable but for my application not something I really need.piston slap , it's not 1960 , my mahle forged pistons never made noise , not like the old heavy forged pistons from the 60's they made noise until warm , still put over 700,000 miles on a 440 over 13 years problem free
Definitely understand, and your doing the right thing by asking questions. But the ballancing concern is something you need to address regardless. The factory ballance job from Chrysler wasn't very good to begin with. There is really no drop in piston that will ballance your factory assembly properly.He was either way he just warned me about tuning and getting it correct or you can create your own issues. Some refused to build at all with them. My big issue is don't want to have to rebalance everything and have a crank that I could never use again. Read a few here and horror stories on confusion what harmonic balancer do I use now torque converter and plate and such. Just trying to take all the information in and weed out the BS and the real facts. HP is great but not at the sake of reliability is also the goal here.
Yeah I'm trying to keep things as simple as possible. I do have a budget I go over it all stops and will sit unfinished for long time. I plan to keep balanced as externally balanced. If I start jerking with that many things have to be changed out and not in the budget to go crazy with that. I'm sure I'm ok so far with what I got basically a stock bottom end more compression. Once I know for sure hopefully the pistons fit the bill if not builder can help guide me right direction.Definitely understand, and your doing the right thing by asking questions. But the ballancing concern is something you need to address regardless. The factory ballance job from Chrysler wasn't very good to begin with. There is really no drop in piston that will ballance your factory assembly properly.
No problem keeping it external, I'm just saying you definitely should re-ballance it after you decide on pistonsYeah I'm trying to keep things as simple as possible. I do have a budget I go over it all stops and will sit unfinished for long time. I plan to keep balanced as externally balanced. If I start jerking with that many things have to be changed out and not in the budget to go crazy with that. I'm sure I'm ok so far with what I got basically a stock bottom end more compression. Once I know for sure hopefully the pistons fit the bill if not builder can help guide me right direction.
If your engine builder has problems with KB hyper pistons breaking, you need a different engine builder.
Thanks for the information that's a big help this is the part that's new to me. But I'm really enjoying it and learning is great.This...
They don't have a clue regarding machining tolerance and/or most important ring gaps. They are likely gapping rings using the .004/inch of bore. If you do that with a hyper, it will break the tops off from rings butting. I've had hypers running a 200 shot and never had a issue.
If they are just pulling rings out of the box and installing them, RUN. TELL them that you want the top ring gapped at .0065/inch. so if you have a .030 360 with a 4.030 bore it's going to gap at .026 and if running a small nitrous unit .030
Bad tune ups kill pistons as well. Detonation is the enemy of all pistons.
All Carter carbs are mechanical secondary carbs. Wire tie the linkage for consistency on the secondary opening.6253s 850 thermoquad. Carb looks great just wanted something with mechanical secondary.
What is with the hate on hyper pistons seems many here use them with no trouble
If your engine builder has problems with KB hyper pistons breaking, you need a different engine builder.
This is so easy to fix;Advance springs sure are easy to change compared to taking the OE distributor apart!
I actually dumped the iron heads for a few reasons and picked up speed master 65cc aluminum ones. Stock 4bbl intake gone air gap style instead. With the kbs if I go that route will be at 10.7 CR to 1 about. The cam I'm running should be better than my first choice with a 1.6 rocker well into 500 duration both sides. This should easily hit my mark for horsepower. Will be a fun driver. I did actually watch these vids along with a few others Simpson speed shop read a great deal on the trickflow build he did and the iterations. They and Edelbrock are way to proud of their chunks of aluminum lol. Cost was insane for what I was planning. This is just my first resto mod and the learning curve mobile. No disrespect but A bodys are affordable and I love them. When I move up I won't jerk around on a triple the cost car. Here I can learn I screw up I can afford to go at it again.I am NOT a builder; but I think I designed at least one pretty good engine.
My Eddy-headed 367 has been running KB107s since 1999, and currently has over 100,000 miles on it.
In the beginning, this engine had a lotta trouble with running hot, that I could not solve. This engine was not assembled by me, on this first iteration.
Finally, I tore the engine down and sent the block out for honing a lil more skirt clearance ( the bore is reported to be 4.045 now) and got me some Plasma-Moly file-fit rings. I opened up the top gap to .032, and Second was .026 IIRC.
BAM ! instant heat relief.
I now run a minimum coolant temp of 207*F, on purpose, and she is impossible to overheat, running the same parts as when it ran hot.
On Day-1, my KB107s fell in .012 below deck.
I tried to run an .028 gasket for .040 Quench; but at the first scheduled tear-down, I found that the Fire-ring was migrating towards the valley and was only a short time from letting go. Good catch.
So I sent the block out to zero-deck it, to use the famed FelPro 1008s. The new Q was thus .039.
A couple of years later my cam spit off lobes, so on the Fourth inspection, I decked the block again, to get the pistons to pop up a lil to maintain the cylinder pressure with the new bigger cam. The new Q is about .032 with the .039 FelPros.
Cylinder Pressure on all three iterations was thus maintained at or nears 180psi. And all three iterations ran on 87E10 without detonation.
My car is a manual-trans car, so I do not have the option of a Hi-stall, so it has to perform right down to idle-speed. And with the high cylinder-pressure, it does. So much so that I have to retard the ignition below 700rpm to operate down there, without the power overwhelming the driveshaft.
If your pistons also drop in at .012 below-deck, and
if you also use the .039 gaskets with those closed chamber heads;
then your Q will be about .051..
They tell me that is about the maximum for Q to be, to still be considered a Quench-engine. And they say, usually talking about iron heads, that Q of this magnitude, occasionally elicits detonation on anything but best pump-gas. But I think with alloy heads, you should be fine.
As to balance; just get it done.
The KB107-Hypers are so light (502grams), that the Engine wants to rev like lightning. With decent springs, mine revs to a self-imposed red-line of 7200, and in the first two gears at WOT (with 3.55s), I can't hardly shift fast enough to not bang off the rev-limiter. Your engine will thank you for it.
With the Late-Closing Intake event of that Mutha cam, your cylinder pressure will not be very high even tho your compression ratio might be. That translates to a modest amount of sub 3000rpm Power. So try not to stall it too low.
The Desk-Top Dyno was Waaaaaaaaay off on my build, the car just barely got into the 12s (12.9@106mph). Which at 3650 race-weight, I think translated to 335 hp. That was with the Hughes HE2430AL cam;
270/276/110; 223/[email protected]; and lifts of .538/[email protected]. Great street cam, BTW! This combo ran a short time at 11.3Scr at 192psi. yes still on 87E10
I also run extra oil to the top end in an effort to cool the valve springs, and to help the aluminum roller-tipped 1.6 arms to survive. Since those rockers currently have over 100,000 miles on them, I think it must be working.
And I drilled the tops of my rods to try and grab some lube. And I slightly enlarged the spray-holes in the rods, that spray onto the cylinder walls.
Don't forget about the other Oiling Mods, and I highly recommend an extra capacity oil-pan to help cool the oil that is getting beat up pretty bad by all these mods. To support all that, I run a hi-volume oilpump, for which I had to modify the filter baseplate so it wouldn't blow the filter off. lol.
Good luck on your combo; It's getting to look a lot like mine except not the cam. I think you wouldda liked the 268 better...... but what do I know.
Happy HotRodding
EDIT;
BTW, take a good look at this graph, notice that, not including the baseline; below 3200rpm, nothing much changed. And that nothing really gets going until about 3800/4000. It's a good thing you'll be buying a TC.
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