Stroker Questions

[Mosca]

Hello,

I need some advice/info regarding installing a stroker crank in a blaster. I did a search for stroker to see if this question has been answered already but figured I'd start a new thread. It seems there are two options, the first being the Hot Rods +4 Crank and the second being the Vitos +3 using a spacer. So, my question is, will either of them require trenching or any grinding of the cases? I know with the Hot Rods the head has to milled 2mm deeper, but what about the bottom of the stroke? And basically is it the same for the Vitos kit? Also, I know porting makes the best power, but is it required when you put in a stroker crank?

I guess what I am wondering is whether it is a matter of buying/installing the stroker crank, having the head milled and putting back together, or is it also going to require trenching/grinding the cases and porting as well?

Thanks in advance for any info.

 

[Surfrjag]

the +4 requires trenching and the +3 does not however it would be a good idea to check clearances before final assembly anyway. the +3 crank comes with the base spacer and can be run out of the box however benefits from porting for the longer stroke and removing the spacer by machining the head. this reduces crank case volume even more and typically nets more power be sure do replace all the seals in the crankcase while your in there.

 

[scotj77]

x2 on that one. he said it all

 

[sicivicdude]

Sometimes, because of tolerances in case casting, the very front and back of the cases need "trimming" even with the +3 crank. It's a little more than sandpaper but not nearly as difficult as the trenching that the +4 crank needs.

The vito's crank includes the spacer so you don't HAVE to do anything to run it. You can run it with a stock top end. I am right now... but in order to see the biggest gains from either crank modification you would need the top end specially treated (ported) for the modification.

 

[Mosca]

Alright nice, that is what I was gathering but information is sometimes hazy or even contradictory online so I wanted to see what general concensus was, I saw that the vitos may require some light grinding but I know that cleaning up some casting lines is WAY different than grinding the case, I really think I am going to stay away from the +4, just doesnt seem like its worth the effort/money/sacrifice in reliability for 209cc or 211 or whatever it will be with a 66.5/67mm bore.

Now, I know this might start some arguing, but does it really make a difference using the spacer versus having the head milled for the vitos kit?