They are 100cc heads. How thick is the head gasket? Domed pistons on that Eagle kit?
https://eaglerod.com/item/5527353-co...v-tall-454-1pc
They are 100cc heads. How thick is the head gasket? Domed pistons on that Eagle kit?
https://eaglerod.com/item/5527353-co...v-tall-454-1pc
This sounds shady. The piston size and intended use will dictate the final bore size when done correctly.Originally Posted by oldpartsnrust
-3CC dished
So they say to add to the volume as a positive value in the calculator.
I ordered head gaskets (Cometic) that are 0.075" thick
Last edited by oldpartsnrust; 4 Weeks Ago at 10:04 PM.
Yeah, I was not all that happy when the guy told me 4.315" bore... This time I sent the pistons with the block, they came back numbered and fitted per cylinder.
Block is ready. Supposedly the line hone/bore is 'tight' whatever that means and the pistons are fitted to each cylinder. I guess that means that each cylinder was bored to match the piston? New cam bearings and the freeze plugs were already brass, so they are O.E.M. I will post pics of the block once I get it back. It was done on Thursday, but just getting out of the hospital sapped a bit of ambition. Couple that with the fact that a tropical storm was indiscriminately dumping rain all over the place AND that I have an open trailer, I decided to wait till Monday.
Anyone care to check my compression calculation? (No, I won't blame anyone if it is wrong and I blow it up. I've already done that myself and I own it!).
deck height: 9.780" (0.00" piston clearance)
piston volume: +0.183" (+3 CC dish style)
combustion chamber size: 6.102" (100 CC)
head gasket bore: 4.500"
head gasket thickness: 0.075"
cylinder bore: 4.310"
stroke: 4.25"
I came up with 9.3:1
anyone?
Last edited by oldpartsnrust; 3 Weeks Ago at 01:25 PM.
Block is now home safe:
BlockTake2a.jpg
Bored to pistons:
Pistons5-7.jpg Pistons3-4.jpg Pistons2-6.jpg Pistons1-8.jpg
Last edited by oldpartsnrust; 3 Weeks Ago at 10:44 PM.
So after struggling with the spirolox removal and seeing that everyone else struggles with it like I do.... I took a 1/4" drive flat blade screwdriver bit and ground it down on an angle and it worked amazingly well at prying out the edge to be able to be grabbed by pliers for removal... Once you can pry the edge out of the groove and get it grabbable, it is game over for the keeper!
SpiroLoxToola.jpg
Last edited by oldpartsnrust; 3 Weeks Ago at 12:39 AM.
Ok, learning a bit more about ping, quench height and CR. Looking at 0.036 with the current deck height and an 0.030 Head gasket. 10.1:1 if I get 4.630 bore gasket. Thinking my previous 0.030 quench height may have contributed to ping?
I'm getting 10.05:1 CR with the 0.030" gasket and .006" deck clearance. 8.39:1 DCR with the cam 212/218 .510/.510 113+3 and 6.135" rod. Kinda pushing it there with that chamber design and iron heads.
Since the heads are off now would be the time to do some bowl work, especially on the exhaust side.
Last edited by SiriusC1024; 3 Weeks Ago at 11:40 PM.
Tight quench reduces knock sensitivity, even when tightening it up increases the C.R. Proper quench is much more important than static or dynamic compression for a pump gas street engine. If you can run .036" without the piston rock causing a collision (depends on bore size, and piston/wall clearance) you aren't going to get much better than that, increasing it will only make it more knock-prone.
Loose piston/wall, and larger bore needs more piston to head clearance to avoid contact which will pinch the top ring land.
The Internet says dynamic compression is something you should pay attention to, engines built in the real world say that it's not. Keep the quench tight and it will be fine.
GM Gen4 Injectors v2.1.xls
ChatGPT is the end result of someone assuming that if they gather up a large enough pile of sh*t it will spontaneously generate a pony.
Yes the quench is pretty good. If it does knock it can be brought in with timing adjustments.
Ok, so I took a look at the block to verify the deck # and apparently I misread it the first time around. It is 9.794".
Additionally, the rod lengths are 6.385". Not sure if that affects the dynamic CR or not as I don't know how to calculate that myself yet.
I took a pic of what was stamped into the block.
Deck.jpg
IF my assumptions are correct now, this would give me 0.014" deck to piston clearance (to be verified once I get the crank and at least one piston in to check with feeler gauges and straight edge). SO, the gasket I got has 4.370" bore and 0.030" compressed thickness. This would give right around 9.9:1? I ALWAYS put premium in everything I own, even my freakin free lawn mowers.... So around here the minimum I have seen is 91 and it is usually 92. Upstate in NY I have seen as low as 89, but I have octane booster as well.
Deck Height: 9.794
Bore: 4.310
Stroke: 4.25
Gasket Bore: 4.370
Compressed Thickness: 0.030
Cylinder Head Volume: 100CC
Piston Head Volume: 3CC
Compression Height (in.): 1.270 in
Stroke: 4.250 in
Rod Length: 6.385 in.
Advertised Intake Duration 264
Advertised Exhaust Duration 270
Intake Duration at .050 Inch Lift 212
Exhaust Duration at .050 Inch Lift 218
Intake Valve Lift 0.51
Exhaust Valve Lift 0.51
Lobe Separation 113
Valve Timing Lift 0.006
Exhaust Close ATDC -6
Intake Open BTDC -5
Exhaust Open BBDC 44
Intake Close ABDC 37
Lifter Style Hydraulic Roller
Compression.PNG
If I remember correctly, the knock sensor was always reading knock? I am still hoping that this was a result of the oiling issue causing valvetrain noise which was being interpreted as knock? I also recall that the addition of octane booster did nothing to the sensor reading?
Assuming these measurements are correct, then the quench would result in 0.044" (which still seems to be in the target range?) and compression of 9.9:1 without fiddling with any head work or anything like that? I only say that because this is simply the family tow vehicle and should never see the northside of 5000RPM. I do expect to be towing about 4000-5000lbs through the mountains which is what took out the stock 454 at 179,000 miles AND an oil diverter baffle failure that wedged it into the oil passage resulting in a death rattle when I tapped the brake after the cruise had a downshift and rev to 5000RPM (4 rods spinning at once is what it looked like when taken apart...)
Sounds like this is a feasible combination? I originally was shooting for lower compression, but thought my heads were 110CC and not 100CC....
Edit: I also have a 4-row aluminum radiator.
Last edited by oldpartsnrust; 2 Weeks Ago at 04:53 PM.
Just so it is all here instead of scattered all over my shed/workbench and various notes:
Factory Spec Journal Diameter:
Mains - 1-4: 2.7494, 5: 2.7488
Rods - 2.20"
Measured Journal Diameter:
Mains
1 - 2.74955"
2 - 2.74935"
3 - 2.74945"
4 - 2.7494"
5 - 2.7486"
Rods:
1 - 2.1999"
2 - 2.1999"
3 - 2.19995"
4 - 2.1999"
Rod Positions:
1 - Ser# 04092
2 - Ser# 03878
3 - Ser# 04651
4 - Ser# 04020
5 - Ser# 04111
6 - Ser# 08082
7 - Ser# 04001
8 - Ser# 04170
Rod Torque Spec (ARP): 63 Ft/Lb
I reviewed the tops of the pistons I removed and saw zero evidence of any pitting or other signs of detonation nor any signs of contact with heads, valves, etc. There was ample evidence of swirl in the carbon build up patterns from when it was running rich before the tuning started.
SwirlCarbon.PNG
I was running 9.780" on the block so there was 0.000" clearance and the 0.030" gasket gave a quench of 0.030" (dumb luck). The knock sensor was reading knock, the valvetrain was making every conceivable noise you can think of and the engine ran a little sluggish. I added octane booster on top of the 92 octane gas that I run all the time and it did zero for the knock sensor readings. Disabling the knock sensor made it run fantastic, even if it was only for one jaunt around the block, but I could tell the difference immediately. Figuring that the new block now has deck clearance of 0.014" and I will be using the same 0.030" head gaskets it comes out to 9.938:1 via the calculator. The quench will be 0.044" which is still inside the 'recommended' range, but a 0.001" but hey, It's in there! Assuming that any knock could be tuned out with timing or other tweaks, I think this is what I want to run. Unless anyone has any reason that I should change something? By all means please add any input. I was also considering the 0.040" head gasket that gets it to about 9.6:1, but sacrificing quench, which would be at 0.054". But for now sticking with the 0.030" and 9.938:1.
Long story short, this thread may be back on-track with TUNING shortly here....
Last edited by oldpartsnrust; 1 Week Ago at 01:52 PM.
Got rings fitted. Hayes file fit on hypereutectic KB pistons. 0.029" for top ring, 0.023 for 2nd. ring. Going for crank bearing clearances check and install next.
Got pistons, pins and rods sorted:
#1. 1615.23G
#2. 1615.41G
#3. 1615.12G
#4. 1614.93G
#5. 1615.15G
#6. 1615.18G
#7. 1615.33G
#8. 1615.03G
Last edited by oldpartsnrust; 4 Days Ago at 10:08 PM.
Did you happen to check bore clearance on the skirt?
I did not. I left that to the machine shop. SUPPOSEDLY, they fitted each piston to each bore and then stamped the pistons with the cyl #. I had given them the block, pistons and spec sheet that came with the pistons. I'll see if I can figure it out.... I don't think my tools measure that big, but I will check.
EDIT: Ordered a 4-5" micrometer (el cheapo) and should be here Thursday. I'll give it a go to see what I can come up with.
Last edited by oldpartsnrust; 3 Days Ago at 06:34 PM.
Ugh, Amazon 2 day delivery turned into 3 day again... I don't mind 3 day, but DON'T LIE and say 2 DAY!!!
Also, looking at the Factory specs, the 'builder recommended' clearances would have put the crank in 'out of service range'. The factory spec is different for each main journal almost:
MAINS:
#1 - 0.0017" - 0.0030"
#2-#4 - 0.0011" - 0.0024"
#5 - 0.0025" - 0.0038"
RODS:
0.0011" - 0.0028"
I am going to try to stick to the tighter end of the spectrum.
Last edited by oldpartsnrust; 1 Day Ago at 05:30 PM.
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