As I'm looking at the front & rear plates of my 13B-REW engine, im wondering if this may be a cost effective option. (if you were planning on porting teh engine anyways)

I understand that the OEM ports will be slightly off, but that could be worked out via street porting.

All the casting is there already, just no holes drilled.

 

Cost effective option for what? Do you already have a 20B that needs replacement front and rear irons? If not, converting a 13b-rew to a 20B is never the "cost effective" way to go. You are much better off just buying a 20B long block and rebuilding it. This way you get the expensive parts like the e-shaft and thick center iron, not to mention all the peripherals that would need to be sourced individually.

BTW the porting is a way more that "slightly off", the 20B intake runners are huge in comparison to the 13b-rew. Without some pretty fancy machining it would be very time consuming to port match the runners height and width.

 

I already have my 20B block. (dry sump, peripheral port is the plan)

I was just thinking out loud, seeing what you guys thought.

 

I am using a REW rear iron on my 20B, it was no big deal to modify it for 20b size ports and drill it out for the 2 big tension bolts. The front iron would be harder as you would have to machine flats but still not a huge deal.

 

Removing a 1/2" of cast iron evenly throughout the runner is not a breeze

20B gasket on top of FD gasket

 

Or you could use 13bre plates instead, which have the same ports as the 20b

 

Machining the 13b front and rear plate for the 20b also porting to match will not be a big deal.. 1 thing to keep in mind. The rear plate will be best to go with a auto 13b rear plate , reason ... the 13b auto rear plate has the extra material around the 12.7 mm stock tension bolts. Were the 13b manual plate does not pics for reference.
Hope that helps
Chip U
ChipsMotorsports.com


Uploaded with ImageShack.us
13B auto rear plate
Note the material thickens around the tension bolts for 12.7 mm 20B thick bolts.


Uploaded with ImageShack.us
13b manual rear plate ..
Note the material thickens.. how much less material is there.

 

Awesome!

Glad to hear this is an option.

As I said earlier, I plan on peripheral porting my engine, so port matching isn't really an issue.

Thanks for the imput fella's