Stroker Questions

wwholden

Member
Nov 17, 2011
962
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54
Dayton, Ohio
I just got my hands on another blaster. The guy didn't know a whole lot about the engine. He said it had a vitos stroker kit. I tore down the top end because it was only getting 90psi of compression. I inspected the cylinder and piston and didn't find any scores at all. The rings dont look burned or anything. Looks like new really. Also the head seems to be milled. Its pretty much flush with the casting. Anyways I saw this base gasket had a metal plate on one side of the green base gasket. I thought this was odd (hows it seal right) so I put it back with just the gasket and not the spacer. Did a compression test and got a little over 100psi. Didn't hear the piston knock the head or anything so I thought it was fine. Engine still isn't making any power though. Not sure if its a jetting issue or what.

How do I tell what crank I have without removing it. Like if its a 3mm or 4mm?
Whats the purpose of the spacer?
Why isn't there a gasket on both sides of the spacer?
If I need a new spacer/gasket what do I need to get?
 
The vitos crank will have bright blue stuffers on the webbs of the crank. That's the only thing I know of unless you can measure the entire stroke. If your only getting 90-100psi something is not right. Use good gaskets (oem or cometic), check all you tolerances in the cylinder.
 
if that is the vito's 3mil crank, and unless the porting has been corrected for the added stroke, it uses a spacer plate to adjust the cylinder/ports
and most definately should have a gasket on both sides of the spacer
i'd also be willing to bet, the way it was is leaking to beat all hell
did you leakdown test it ???
get 2 new base gaskets, reassemble, leakdown test it, then another compression test

it may have also been overbored, or just honed, and that cylinder to piston may be out of spec, then it doesnt matter how many brand new pistons/rings you install, it will not make compression

heres how to measure that............

=
 
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I'm not totally sure on this but I would think if it was a stroked crank, it would hit without the spacer. It is odd that they would have a spacer without a stroked crack. I just wonder if for some reasion, they had the head milled for the stroked crank and ran the spacer to. A pic of the head some may help to determine if it was cut for a stroked crank.
 
if that is the vito's 3mil crank, and unless the porting has been corrected for the added stroke, it uses a spacer plate to adjust the cylinder/ports
and most definately should have a gasket on both sides of the spacer
i'd also be willing to bet, the way it was is leaking to beat all hell
did you leakdown test it ???
get 2 new base gaskets, reassemble, leakdown test it, then another compression test

it may have also been overbored, or just honed, and that cylinder to piston may be out of spec, then it doesnt matter how many brand new pistons/rings you install, it will not make compression

heres how to measure that............

How to measure a cylinder.wmv - YouTube=

Ok that make sense about adjusting for the port timing. The jug doesn't have any signs of any port work at all. But why does the vitos base gasket kit for the 3 mill only come with one gasket.

This looks exactly like what I have (aluminum plate with green gasket):
1.5MM SPACER PLATE WITH TWO...
 
I'm not totally sure on this but I would think if it was a stroked crank, it would hit without the spacer. It is odd that they would have a spacer without a stroked crack. I just wonder if for some reasion, they had the head milled for the stroked crank and ran the spacer to. A pic of the head some may help to determine if it was cut for a stroked crank.

I dont have any pics of the head since I already annealed the head gasket and torqued it on. But like I said the head is practically flush with the casting. My other blaster has a .20 milled head and its no where near flush with the casting on the head. This head also has some weird cyclone (four or five of them) grooves swirling around the dome. But its not the removable type neither. Never seen anything like it before on a blaster head.
 
I dont see anything blue in there guys. Did see some gold near where the rod connects.

Could you run the 3 mill without using the stuffers?
 
I dont see anything blue in there guys. Did see some gold near where the rod connects.

Could you run the 3 mill without using the stuffers?


chances are it is not a 3 mil if the blue stuffers are missing, hence why there was no head interference without the spacer installed ?
 
I dont have any pics of the head since I already annealed the head gasket and torqued it on. But like I said the head is practically flush with the casting. My other blaster has a .20 milled head and its no where near flush with the casting on the head. This head also has some weird cyclone (four or five of them) grooves swirling around the dome. But its not the removable type neither. Never seen anything like it before on a blaster head.

That's odd to have that on a head dome. I know the consept of it but I don't really trust it. I feel it could have a negative effect on combustion.
 
That's odd to have that on a head dome. I know the consept of it but I don't really trust it. I feel it could have a negative effect on combustion.

hollywood dirt was famous for them swirled heads/intakes/exhausts
they are out of business and the owner on vacation at san quentin
 
chances are it is not a 3 mil if the blue stuffers are missing, hence why there was no head interference without the spacer installed ?

Is there any other way to see if this is a stock or stroker crank??? I need to figure this out so I know what type of base gasket to get.
 
Take something like a McDonalds straw. Stick it into spark plug hole. Turn engine by hand until the straw stops moving out. This is Top Dead Center (TDC). Mark it with a fine line. Turn engine till straw stops dropping in hole, this is Bottom Dead Center (BDC). Mark with fine line. Pull straw out of cylinder, measure between two lines
and you have stroke of engine. 3-4 mm isn't much thus the accurate "fine" line when marking. Or you could use a caliper with depth gauge.
Also, originally weren't Vito's cranks without stuffer blocks?

Off hand don't know what stock stroke is.
 
I think it's safe to say you have a stock crank. The plus 3 has the blue stuffer blocks and the plus for doesn't but would of shot the head threw the tank without the spacer. Lol
 
Ok that make sense about adjusting for the port timing. The jug doesn't have any signs of any port work at all. But why does the vitos base gasket kit for the 3 mill only come with one gasket.

This looks exactly like what I have (aluminum plate with green gasket):
1.5MMSPACERPLATEWITHTWO...

the kit you have linked us to, does in fact come with 2 gaskets, read the ad
why your's doesnt have 2, may be the big million $ question, it should/must have a gasket on either side of the spacer.

maybe the P.O. let his kids make paper angels with it ?
thats about all them green construction paper gaskets are worth
 
Is there any other way to see if this is a stock or stroker crank??? I need to figure this out so I know what type of base gasket to get.

Regardless of what kind of crank it is you need to run an oem or cometic gasket. Those green gaskets are junk.