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I.D. this rod
Just broke down a 427 tall deck. I've been told that it's a stroked 482ci. It does have a 4" stroke crank and LS 6 454 pistons but I have no clue what these rods are. They have a number on one side (I cant find anything on it) and the other side looks like its been ground on. It's like that on all 8 rods to.
The number is 621-3404. Any help? http://img22.imageshack.us/img22/3435/z4l6.jpg |
mark they look like stock rods but they are side polished and most likelt shot peened and a good rod bolt installed..you sure its a 4'' stroke? the 427 T D came with 8:1 forged pistons..back in the day we would swap the ctlinder heads with rectangle port heads.add a asolid roller cam and lap a 671 blower on top..quick way to make 650 hp..
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I am pretty sure that is an old Kiekhaefer rod. They were used on the 482's back in the day. But like Fixx says are you sure it is a 4" stoke? The 482 was 4.25
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This is what I've I.D'ed in this motor so far.
Block 340220 .... 427T ...... 68-85 ... 4-bolt 1972-76 427 tall truck ----- Crank 3963521 454 - 4 in stroke, 5140, raw forged –part # 3963524 (The crank has a 3521M on it.) This forged 5140 steel 4.00" stroke crankshaft is the highest quality GM offers for big-block V8s. It is nitride treated to increase its hardness and fatigue strength. The main bearing journals are cross-drilled to provide a constant supply of oil to the rod bearings. For use with Mark IV design engines only. Technical Notes: This crankshaft is externally balanced. It must be used with a counterweighted torsional damper and flywheel (or flexplate) for correct engine balance. Main journal diameter is 2.75"; rod journal diameter is 2.20". Crankshaft ID is #3521.". GM parts direct sells them for $700.60. List is $962.36 ------- Heads 3964291 RECTANGULAR PORT - Valve size 2.19 intake, 1.88 exhaust 1969-70 396/402 375 L-78, Intake Port 325cc 427 425, 435 L-71/L-72 ----- Crane Cams Part Number:138091 Mechanical roller tappet / Grind Number:TR-252/400-2-10 Basic Operating RPM Range:3,500-7,000 / Intake Duration at 050 inch Lift:252 / Exhaust Duration at 050 inch Lift:262 / Duration at 050 inch Lift:252 int./262 exh. Advertised Duration:290 int./300 exh. Factory Rocker Arm Ratio - Intake Valve Lift :0.680 in. / Exhaust Valve Lift :0.708 in. Valve Lift with Factory Rocker Arm Ratio:0.680 int./0.708 exh. / Lobe Separation (degrees):110 Intake Valve Lash:0.022 in. / Exhaust Valve Lash:0.022 in. ------ 3906629 oil pump OEM GM Oil Pump Assembly with P/U For Chevrolet/Corvette Big Block Engines. The part number in the casting is 3906629 GM3 --------- Main Bearing 5203 / .010 Rod Bearing (6) 5177 / .010 - (2) 5177 / .020 ------ Pistons 3999295 454 - LS6 - 1971 - 9:1 Pistons Part number=6262976 Engine=454 Compression Ratio=9:1 Size=Std. Dome Type=Closed Pin Type= floating Should originally be from a 1971 LS-6 -------- Holley 850 D/P list # 4781-2 model # 4150, 850 CFM Dbl pump 80 jets in both ends and a 6.5 power valve in both ends renew kit part # 37-485 |
Also notice the cut on the crank rod journals. Never saw 2 different sizes before (the .020 over size is on 7 and 8's journal).
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Not sure...I will defer to Mark. Looks like a casting mark that a specialty casting shop would use that matches a customers PO #. nice looking piece of hardware BTW.
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Originally Posted by f_inscreenname
(Post 4039502)
Also notice the cut on the crank rod journals. Never saw 2 different sizes before (the .020 over size is on 7 and 8's journal).
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i have never seen that rod before but it looks heavy.
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Yes, they are very heavy! I had 2 sets of them in the 482's that came with my Cig when I bought it back in 1978.
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Originally Posted by Mbam
(Post 4039592)
Yes, they are very heavy! I had 2 sets of them in the 482's that came with my Cig when I bought it back in 1978.
http://img547.imageshack.us/img547/4059/qqyb.jpg Marc, you have any specs on them? Like length and such? Also were your 482's full roller motors? Before I got it I did a little research on the 482. I expected aluminum roller rockers but this one also has a roller cam and lifters, 7/16 pushrods and guides, rotators taken out of the rectangle heads with big valve springs. |
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