RD80LC Barrel differences

[daveheng]

I’m about to rebuild an 80 motor and have the choice of two different barrels I could use, 37a and 30w. They appear to have the same transfer port timing but I have only done this with a steel rule, the exhaust ports are different, the 37a has a raised square section about 6mm wide which increases the port timing before the main part of the port is uncovered. What effect does this have and pros and cons of each, otherwise the ports look the same. 

thanks in advance 

Dave

[daveheng]

I have just found this by doing a general search on the internet which is a previous post on this forum, hopefully the link will work! rdlccrazy.proboards.com/thread/48829/run-deux-exhaust-port-weirdness