[hyper7boy]

My VZ-B V-Spec is in need of a new pistons and sleeve. I was wondering though. With the O.S. Speed piston and sleeve fit in the VZ-B crankcase. Also, I know the O.S. Speed has more power, if I use the piston and sleeve from the O.S. Speed will my VZ-B have that same power, or at least simular. Please, any feedback would be great...

[Speed Metal]

Yep everything will swap over. I believe the Speed case has some differences but I don't think there should be any issues as the Speed's exhaust port is lower and wider than the the regular V-Spec's. So I think it'll be fine.

regards

speed metal

[Dave Henry]

the crankshaft is also timed diferently between the speed and regular v spec, and the oil hole is in the rod not the crank as in a speed,you must use a speed conrod with a speed crankshaft,mixing parts with some v spec and some speed will not provide much if any benefit

in general the v spec has a lot stronger low end hit in power with great midrange power and good top end, it is very well suited to buggy and truggy

the speed is designed specificly for 1/8 buggy (not truggy) and has a softer low end hit to help with traction with a great midrange and screaming top end

the speed only has more "power" at high rpm's, i would not recomend installing just a speed piston/sleeve in a vspec, and you should check the rest of your motor before replacing any parts

the crankpin should be checked for wear, it should measure no less than 4.90mm (if i remember correctly) at it's smallest spot, the crank should have zero play in the bearings and they should be perfectly smooth, also the rod should probably be replaced with a new piston/sleeve

if more than the piston/sleeve/rod need to be replaced i would recomend replacing the engine and saving the rest for parts

[hyper7boy]

Thanks Dave, great info. I am just going to put in the stock VZ.B P&S because like you said, the older one has more bottom end, and it is going in my 8ight-T so...Thanks for the great info.

[Dave Henry]

no problem

don't forget to check the stuff i mentioned

[Speed Metal]

ahhh yes Dave is right. If you wanna do a Speed conversion you'll need to swap over piston, sleeve, conrod, and crank as the crank and rod have different lubrication holes. The regular V-Spec has the lube hole for the conrod cut in the rod journal of the crank whereas the Speed has the hole in the conrod itself like most Italian engines.

So you'd have swap over almost everything except the case!

Good call Dave!

regards

speed metal

[NS]

I am rebuilding a v-spec as well.

The crank pin on my old crank was ovalized, so I opted for the speed crank / conrod ... and of course new bearings.

I was hesitant to play with the stock v-spec as it is such a good all-round engine, but the testosterone guided me the right way to more HP !

[imported_Steve]

Originally Posted by NS

I am rebuilding a v-spec as well.

The crank pin on my old crank was ovalized, so I opted for the speed crank / conrod ... and of course new bearings.

Hey Guy's

I've had 8 V-spec (no joke) and every One of them have had the crank ovaling issue I believe thats the motors weakness.

I Love that motor but it is rare to get a second piston/sleeve on the orignal crank. I think of my 8 motors only 1 got a second p/s.

My friend has the JP mod V-spec and he is on his 4 p/s, because the jp's crank is hardened & coated. Now the Speed's is also.

I don't think is worth the money to take a stock V-spec and change the crank, conrod, p/s to a Speed's.

Just buy a Speed there are many more benifits to Speed over a Stock V-spec. Speed comes with ceramic bearing, it comes with a 7,8,9mm carb restrictors, so if you need more bottom end change the restrictor and get more fuel econamy.

I have read somewhere that some guys in the USA are getting 13 to 15 min. with the 7mm restrictor.

just my thoughts.

Steve

[NS]

Originally Posted by Steve

Hey Guy's


I don't think is worth the money to take a stock V-spec and change the crank, conrod, p/s to a Speed's.

Steve

FYI - The rebuild cost;

Speed Crank - $130
Speed Conrod - $50
Ceramic Bearing - $22

I couldnt afford not to rebuild my v-spec w/ the new hardware...as I have 2 piston / sleeve sets with lots of life left.

[hyper7boy]

Wow, well for the price of everything, I might as well just sell my VZB and get the speen...no?