J/e crossflow v4 mods

[thornl01]

Would like to start a discussion on Mods for the V4 crossflow engines.

Looking for a few more tricks to perform to an engine I am building.

example:

scollops in piston skirt & matching block prep

135 / 140 exhaust manifold.

tuna length ?? & type

have heard that 135 heads are about as tight as you can find.

finding a set of the 8bl carbs is out of the question so has any one tried the larger plastic 1 bls (4of them) from the big loopers.

any suggestions are appreciated.

[PIP]

But i have talked to a lot of experts (well, a couple). This is some basic info, get the specifics from a stoker or a nerstrom;

1) 7 inch tuner

2) 1973 135 heads (but you have to run some really hot gas, like 25% av)

3) crankcase stuffers (the later 110 bubbleback did not have them, but they can be added. This increases crankcase compression)

4) the earlier high ring pistons supposedly get you a little more but they do seem to have some issues with coming apart

5) actually the 1973 135 is probably the strongest performing motor of the v-4 cf but the lower is not a good shape.

6) you can also open up the intake by cutting out the walls separating the barrels, like a yamaha, but you better check with someone on jetting it then.

7) the larger carbs 1 3/8 i think

8) and then of coarse books are written on proper intake and exhaust porting. I think you can basically square up the ports and chamfer the edges and breathing will be better.

Heres a start.

[wolfgang]

Would like to start a discussion on Mods for the V4 crossflow engines.

Looking for a few more tricks to perform to an engine I am building.

example:

scollops in piston skirt & matching block prep

135 / 140 exhaust manifold.

tuna length ?? & type

have heard that 135 heads are about as tight as you can find.

finding a set of the 8bl carbs is out of the question so has any one tried the larger plastic 1 bls (4of them) from the big loopers.

any suggestions are appreciated.

About 17 years ago John Silver wrote a multipage article in Bass and Walleye magazine about how to hop up the V4, complete with part no.s, but without porting details. If you are interested, I can scan and mail to you. Mail your e-mail address to wbarthel@tubular.co.za. rgds, Wolfgang