7afe crankshaft

[starni_boy]

hi,

i need the specs on a 7afe crankshaft, as i am going to get a new one.

i have searched around and found:
bore is 81.0
stroke is 85.5
pistons are 4

is there anything else i will need to add to get the crankshaft made properly? maybe length and flywheel bolts?

i want to put an 8 bolt flywheel so i can run 4age flywheel and clutches.

i basically want a 7afe front crankshaft, with a 4age back crankshaft outside the block

any help is good

[starni_boy]

i made that first post confusing i think..

so basically:

what is the spacing for flywheel bolts on a 4age crank?

what is the length of a 7afe standard crank?

[roadsailing]

what the fuck? you want to get a custom made crankshaft? then you call it a camshaft?

"spline" is irrelevant

your second post isn;t much less confusing than the first.

what are you trying to do? talk us through it

[terryo]

It sounds like you need to do a little bit more research. Whomever you want to make a crank (or is it cam), will have all the data you need. All you need is $ and a clear idea of what you are trying to achieve. Most reputable engineers will then work with you to get your end result.

can supply billet 7A cranks with whatever bolt pattern you want. also available with longer stroke for 2 litre conversions. none of this stuff is cheap. cranks typically $4000-$5000, then you need rods & pistons to match

[starni_boy]

might look into it further.

probably shouldnt have posted so early into research..

[terryo]

yep, you can offset grind the 42mm 4AG crank down to 40mm or even 39mm. that wont even be noticable in performance, just prove a great hassle finding different pistons and/or rods.
we have offset ground the 7A crank and that makes a difference.
you cannot resize the rods to make them smaller. think about it!!, how do you expect to shrink the horizontal width across the bolts.??? rod resizing is what is done to correct minor damage from spun bearings etc.

[beerhead]

Terryo:

I'm very interested in your experiences offset grinding a 7AFE crank. My calculations came to 1.9L or so using a smallport journal sizes. How does it go? 1.9L 20V blacktop 4AGE would be interesting Have you ever done the same thing with a 5S crank and 3S rods? Seems the rod ratio is a little bad on a 5S to begin with I wonder if its a worthwhile mod?

[terryo]

7A can be ground down to 39mm. can do the same with almost any crank. shit of a job however, but a lot cheaper than a custom made billet crank. In every case, you have to do your piston & rod research first, to make sure you dont have an impossible end result. In many cases the rod ratio gets worse, but this mostly effects life. most racers dont care and happily trade torque for life.
terry

[rthy]

its amazing what racers do when they have a capacity limit and rpm limit isnt it? cant blame them