i want to strok my blaster and need some help puting together a parts list of what i need. thanks for all help.
4mm stroker
- Thread starter assumedruz
- Start date
First off, what's the intended use of your setup? Are you setting up for competitive drag racing?
If not, perhaps consider the Vito's +3mm stroker crank. It has the advantage of getting the piston crown below the transfer ports without the disadvantage of having to thin the cases in the critical case sealing area where the cases meet (called trenching).
I'm running a vito's +3mm stroker and would recommend it to anyone but the most hardcore drag racers.
Also, to do a crankshaft swap, you NEED a flywheel puller, impact screwdriver, crank puller, either a purchased or homemade clutch holding tool, mapp gas torch, new crank bearings and crank seals, *probably* a complete gasket set but definitely a top end gasket set, and a bunch of baggies for bolt storage. Plus the obvious; screwdrivers, allen wrenches, pull bar, ratchet, and sockets.
Splitting cases isn't rocket science and can be done by a total amateur mechanic as long as the service manual steps are followed to the letter and you have the right tools to do the job.
Splitting cases isn't rocket science and can be done by a total amateur mechanic as long as the service manual steps are followed to the letter and you have the right tools to do the job.
the +3mm is alot less work, either way you need to have your cylinder ported to match, i love my +4mm
heres my take on this
the + 3 cranks use a smaller "big end" on the rod, versus the larger/stronger "big end" on a +4's rod, hence the need for trenching
so you have a choice, stronger crank or stronger cases without the trenching ?
the blue plastic stuffer blocks on the +3 cranks have been know to work loose rubbing the rod (really ?...plastic pressed in pieces on a crank ??? brilliant !!! IMO.)
the only plus i can see with a + 3 over a +4, is it can be done at home by anyone with a manual and moderate skills
but......
the +4($159) hot rods cranks are $20 cheaper than the +3's($179) on ebay and with the +3 "DIY" needing $130 worth of specialty tools to do it at home,
thats an extra $150 for the "DIY" +3
it may actually be equal $$ to send it to a pro and have the +4 crank ??
given the choice i'd go hot rods +4
the + 3 cranks use a smaller "big end" on the rod, versus the larger/stronger "big end" on a +4's rod, hence the need for trenching
so you have a choice, stronger crank or stronger cases without the trenching ?
the blue plastic stuffer blocks on the +3 cranks have been know to work loose rubbing the rod (really ?...plastic pressed in pieces on a crank ??? brilliant !!! IMO.)
the only plus i can see with a + 3 over a +4, is it can be done at home by anyone with a manual and moderate skills
but......
the +4($159) hot rods cranks are $20 cheaper than the +3's($179) on ebay and with the +3 "DIY" needing $130 worth of specialty tools to do it at home,
thats an extra $150 for the "DIY" +3
it may actually be equal $$ to send it to a pro and have the +4 crank ??
given the choice i'd go hot rods +4
It's true that the way a +3mm stroker crank can be put into a stock case is by making the big end thinner. I don't believe this significantly reduces con rod strength as big end BEARING failures are FAR more common than big end rod failures. Big end bearing failures generally happen due to air leaks or improper maintenance/jetting. Both are MUCH more common than broken rods....
The trenching process leaves two VERY vulnerable areas of case, one between the balancer shaft and crank and one between the transmission input shaft and crank. Those areas, if the case is properly trenched, have less material left than is removed. In other words, you're taking out over half of the material of the case. Something as small as a reed cage screw would then take out the entire trenched area in those cases. I'm not advocating sending reed cage screws pouring into any bottom end but if it does happen, I'd rather not ruin a set of cases over it.
I have heard tale of the stuffer blocks coming loose but never actually seen it myself (or any pictures, or hell anyone who's actually ever had it happen to their crank say so).
The advantage of having the tools to do your own bottom at home is that you have those tools forever more. You're also forgetting the cost of having the cases trenched (an additional charge on top of bottom end reassembly). On the off chance you do find someone who's willing to do a trenching job and bottom end reassembly for less than $130 (not likely!), that's a one time charge. If, the next year, a case bearing flys apart (which has nothing to do with the discussion of +3 or +4mm stroker) you have to pay AGAIN to get that bearing changed instead of already having the tools handy to be able to do it yourself.
For every use, OTHER THAN TOP LEVEL COMPETITION, I'd prefer a +3mm stroker crank over a +4mm stroker crank simply because of the ease to install and the lack of need to modify the crankcase.
/\/\ i gotta agree with that
i must have had somekind of temporary "quest for max powaa" induced brain hemmorage influence my thinking.
and never thought of the reedcage screw scenario, as my reedcage of choice doesnt use screws
a +3 is prolly the simpler, cheaper, better choice for the 99% majority of hardcore trail riders on here
i must have had somekind of temporary "quest for max powaa" induced brain hemmorage influence my thinking.
and never thought of the reedcage screw scenario, as my reedcage of choice doesnt use screws
a +3 is prolly the simpler, cheaper, better choice for the 99% majority of hardcore trail riders on here
as far as crank goes, theyre both very well built, long lasting, quality cranks and its only a matter of how much you
want to shave off your case bottoms. Splitting the bottom end on blaster motor is so easy id kick myself in the nuts
if i paid someone else to do it. (literally)
just like civic said, in the rare event something or anything goes wrong your just going to have to do it all over
(or re-pay some drunk clown in some peoples case) so if your sticking with the blaster for a while id man up,
follow the manual step for step and git-R-done. your also going to learn a couple hundred things which is never a bad thing in my book
heres some vids that will help you tremendously
want to shave off your case bottoms. Splitting the bottom end on blaster motor is so easy id kick myself in the nuts
if i paid someone else to do it. (literally)
just like civic said, in the rare event something or anything goes wrong your just going to have to do it all over
(or re-pay some drunk clown in some peoples case) so if your sticking with the blaster for a while id man up,
follow the manual step for step and git-R-done. your also going to learn a couple hundred things which is never a bad thing in my book
heres some vids that will help you tremendously
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