cylinder bore

JasonAG · Post by **JasonAG** » Sun Oct 01, 2006 10:30 pm

is there a difference between the bore in the 4g63 and 4g64? in other words, im going to be making a hybrid and i want to know if the 4g63 pistons will work with the 4g64 block.

JasonAG · Post by **JasonAG** » Sun Oct 01, 2006 10:55 pm

Hey Mike!!! The search isnt working!!!

Robert Venable · Post by **Robert Venable** » Mon Oct 02, 2006 3:22 am

4G63 has an 85mm bore and the 4G64 has an 86.5mm bore check out http://en.wikipedia.org/wiki/Mitsubishi_4G6x_engine for alittle more info.

Post by **DJpowerHaus** » Mon Oct 02, 2006 12:05 pm

But you can only get .020 over 4G64 Wiscos... so plan on 87mm. I might try to make some connections at an upcoming Mitsu meet. If so I'll try to get a few 87mm bore factory head gaskets for you guys to buy at cost.

skizzo · Post by **skizzo** » Mon Oct 02, 2006 12:27 pm

The 4g64 deck height is also 6mm taller than the 4g63, so the piston's wrist pin is 3mm lower in the piston on the 4g64 pistons. If you use an overbored 4g63 piston in a 4g64 block, you'll have really low compression

Post by **DJpowerHaus** » Mon Oct 02, 2006 1:40 pm

And with you're really low compression you can run really high boost and blow the stock piston right in half just to make the same power.

JasonAG · Post by **JasonAG** » Mon Oct 02, 2006 4:45 pm

so... what is the result, compression wise, with just putting the '63 head on the '64 block? and about how much hp can the stock 4g64 internals out of.... say... a d50/MM, handle?
thanks!

p.s. im gonna post a few pics of my colt soon.... if anyone cares i guess.

JasonAG · Post by **JasonAG** » Fri Oct 06, 2006 8:55 pm

soon i am going to assemble parts i need so i can throw a new motor in my colt this winter. i think what i want to do is get a 4g64 from a d50/mm with reasonable miles and i know where i can find a b2600 BH and my freind is giving me his old tranny when he does the 13b swap in his rx-7 so ill have that. and im going to just put that setup in and get all the fabrication out of the way and just run the NA for a while. so when i decide to, what do i need to do to throw the 1g turbo head on?
thanks

Post by **DJpowerHaus** » Fri Oct 06, 2006 11:43 pm

Most of the fabrication will come with the DOHC head and turbo setup. Why not use a Starion transmission?

JasonAG · Post by **JasonAG** » Sat Oct 07, 2006 6:45 pm

its just as easy for me to find the rx7 setup so thats what im doing

and its cool

rarson · Post by **rarson** » Fri Oct 27, 2006 1:12 am

Is the RX-7 tranny a TII tranny? Because even if you wanted to use the weak N/A tranny, the bellhousing isn't detachable like the TII tranny.

Though I'm assuming if you've looked into it already, you already know this. I've got 2 N/A trannies sitting around, I'm not sure I really want to use 'em since they break so easily...