Hawaiian 512 Stroker Build
- Thread starter gill4321
- Start date
451Mopar
Well-Known Member
0.030" over is a 505" stroker, but it is common for people to call it a 512"
gill4321
Well-Known Member
So a .030 over 4.25 stroke with a 4.35 piston and a 7.1 rod isnt a 512??? If so 440source labeled their stuff wrong.
451Mopar
Well-Known Member
If you go 0.060" over (4.380") the displacement is 512.29". Just about any stroker kit calls the use of a 4.25 stroke crank in a 440 (4.320" to 4.380" bore) a 512 stroker kit. The 0.060" over bore is also not as common as a 0.055" over bore because the selection of pistons rings (and cost) are much better with the 4.375" over bore. With the 0.055" over pistons, they really should call the stroker kit a 511" lit (511.12").
At 0.030" over (4.350" bore) the displacement is 505.3"
If you are going to use a manual transmission, the crank bore for the pilot bushing will need to be finished to the correct size, or you can just use one on the roller pilot bearings that goes into the larger crank recess for the torque converter.
make sure the check the connecting rod side clearances. My stroker kit (from many years ago) had one rod where the bearing locating notch was machined a bit off, and moved the rod bearing a bit too far towards the crank radius which pushed the rod inward reducing side clearance to almost nothing.
The kit also comes with file fit piston rings. Did the shop fit the piston rings, or are you fitting them?
The cam bearing is not ideal, but should be OK? Part of the problem is the cam bearing has the holes slightly off, which seems to be pretty common. I uses the DuraBond PDP-17 cam bearings and the holes are still a bit off. How does the hole align coming from the crank?
gill4321
Well-Known Member
Everything went together well and has proper clearance. I have a good feeling about this build. I did the file to fit piston rings myself. I made sure after the gap was set that I deburred the ring edges carefully. I also dont get hung up on engine size with it being that little of a discrepancy. I believe I can call it a 512 since that was what was ordered. I realize it may be of by 7 cubes but meh...
wyrmrider
Well-Known Member
A blower can make up for those missing cubes 
1967coronet440
Well-Known Member
Lol I’m still trying to figure out what ci mine is lol, originally I thought it was a 535 because I thought my builder used a 4.5” crank, he had the wrong part number on my invoice. When I questioned him on it he tells me it’s a 512 but I knew that a .030 bore and 4.25 throw is a 505 but when I look at the eagle kit it says 512 also so that’s what I’m going with I guess lol.
IQ52
Well-Known Member
Funny, I have good feeling about it too. Dunno, but it sounds like you are doing a good job. Maybe though it's because when I think of 'Hawaiian' and 'Mopar', I remember Roland Leong and "The Hawaiian"? Saw that Charger in the 60's when I was a kid.
68 HEMI GTS
Well-Known Member
3.14 x radius squared x stroke x 8
68 HEMI GTS
Well-Known Member
4.350/2 = 2.175
2.175 x 2.175 x 3.14 = 14.85
14.85 x 4.250 = 63.13
63.13 x 8 = 505
My 512 is actually a “511” on a .035 over 400
451Mopar
Well-Known Member
My low deck 400 with 4.15" stroke and 4.375" bore is really a 499.10 cid engine, but I call it a 500" stroker. It sounds right because the model of my Charger is a 500
Curious what ring gaps did you go with?
I believe I used 0.019" to 0.020"
Curious what ring gaps did you go with?
I believe I used 0.019" to 0.020"
gill4321
Well-Known Member
I went with .020" better safe then sorry. It will be a street engine.My low deck 400 with 4.15" stroke and 4.375" bore is really a 499.10 cid engine, but I call it a 500" stroker. It sounds right because the model of my Charger is a 500
Curious what ring gaps did you go with?
I believe I used 0.019" to 0.020"
IQ52
Well-Known Member
And the gap on the second ring?
gill4321
Well-Known Member
Also .020"
I went with .024 and .026 on my ring gaps. During the dyno runs, on the last run we hooked up a vacuum pump to see what difference it made. It ran the same numbers with the vacuum pump as without.
IQ52
Well-Known Member
On the big bores at rpm (about 4,000+), we found we were getting ring flutter and big blow-by until we opened the second ring gap to .025-.026".
I called the ring manufacture and told them and they said, "Yeah we know."
So I told them their instruction sheet still said to have a tight ring gap on the second ring!
Their answer was, "Yeah, we know."
What the heck! Do they have hundreds of boxes with bad instructions they are just trying to use up?
Don Chapel
Well-Known Member
Hey, which cam did you go with?
TetanusShot
Well-Known Member
Yikes! What brand? Total Seal? Hasting's?
How do you know when there is ring flutter? Noise? After disassembly? The blow-by?
(Running a 4.5" bore with Total Seals)
----
The rings I used were Total Seal. I checked back on my notes and I had noted that I had gapped both the top and second groove at .025
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