what is the biggest cylinder bore possible on the 7m i've seen once a guy claimed .80 over the biggest i've seen is .40 so what is the limit?
Biggest Cylinder Bore Possible
- Thread starter Boss302
- Start date
Depends on each block due to Core shift some will go big and others won't.
My brand new Late model block has a LOT of shift compared to my old 86.5 one!
My brand new Late model block has a LOT of shift compared to my old 86.5 one!
30 over is safe for sure. You could also have the block sleaved back to stock.
If you go too much, you run the risk of too hot, and then the cylinder will distort. Depends what you plan on doing, and how much strain you are gonna place on it.
If you go too much, you run the risk of too hot, and then the cylinder will distort. Depends what you plan on doing, and how much strain you are gonna place on it.
mrnickleye said:
Doesn't work too well with thinwall siamese bore motors
(you make a big wet noodle)
To add to that.
I inquired with someone that ran a lot of mods. The 85mm piston kits didn't last too long. Not the piston, the block.
Ive gone a ants dick over .40" to suit my je's.Noproblems but Ive only done around 2000kms/3months.
this is an old thread, but it needs so revival for my cause. What is the biggest safe bore in mm? some say 85..other 84..86...anyone have a definate idea? The reason I ask is that in the near future I want to build an ultimate streetable NA motor. And that requires getting it as big as possible. I already know the stroker kits can goto 102-104mm or higher, but thats more than I want. I was looking for more like 102. And with 84mm pistons id be looking at 3.39 liters. I was aiming for 3.5, but a little less wont hurt. This is a 7m-ge btw. I was just wondering are 85mm pistons safe(that would get me 3.47L @ 102mm stroke), and what are the chances of breaking the block, overheating, etc. And does any machine work have to be done besides the bore itself? As in, anything in the way. any help appreciated!! This motor would also probably make the better part of 300 crank hp with a slight bump in compression over stock and otherwise stock top end parts. And the future would be a totally done up head, cams, with header, some kind of intake manifold modification, etc.
Isphius said:
Sigh.. There is no definite answer to this because there is variation within each block. The only way to be sure is to have YOUR block tested.
I've seen motors go .040 without problem. I've seen other people hit core shift (read cylinders not spaced propertly) or other casting imperfections on the first slight overbore. It's the luck of the draw...
Overboring is not a valid way to make power. Read this:
http://www.supramania.com/forums/showpost.php?p=180360&postcount=10
Cliffs: You want to go as SMALL as possible, not big. If you want to make big power there are better places to spend the money. For example, make the head flow...
Late Model block has 2mm thicker walls but they're prone to core shift so as Mike said you need to have your own block sonic checked and even then it's risky if there are any inclusions in the metal when it was cast....
For me with a 7M it's the bare minimum required to get straight and round holes then if I need more power it's crank some more boost in.
The other bad side effect of large bores is they tend to run hotter which in a 7M is a disaster waiting to happen.
For me with a 7M it's the bare minimum required to get straight and round holes then if I need more power it's crank some more boost in.
The other bad side effect of large bores is they tend to run hotter which in a 7M is a disaster waiting to happen.
miggles said:
Australian standard? How many ant's dicks make up a mm?
And are those African, Asian, or N American ants?
IJ. said:
Seen this one myself...especially in 110+ temps like Phoenix in the summer!
JustAnotherVictim
Supramania Contributor
I do
"Although a definitive answer would of course require further measurements, published species-wide averages of wing length and body mass, initial Strouhal estimates based on those averages and cross-species comparisons, the Lund wind tunnel study of birds flying at a range of speeds, and revised Strouhal numbers based on that study all lead me to estimate that the average cruising airspeed velocity of an unladen European Swallow is roughly 11 meters per second, or 24 miles an hour."
Taken from
"Although a definitive answer would of course require further measurements, published species-wide averages of wing length and body mass, initial Strouhal estimates based on those averages and cross-species comparisons, the Lund wind tunnel study of birds flying at a range of speeds, and revised Strouhal numbers based on that study all lead me to estimate that the average cruising airspeed velocity of an unladen European Swallow is roughly 11 meters per second, or 24 miles an hour."
Taken from