Side by side image of 643 vs. 561 castings inside..
#1
Side by side image of 643 vs. 561 castings inside..
Who knew they were so different?
These are a set of 643 casting I purchased on the left next to the 561 castings I pulled off my car on Saturday.
The 643's are on their way to Lloyd..
These are a set of 643 casting I purchased on the left next to the 561 castings I pulled off my car on Saturday.
The 643's are on their way to Lloyd..
#3
Re: Side by side image of 643 vs. 561 castings inside..
Go figure, that being said.. the 561's look more "finished".. not sure how that affects thing in the flow department really. I think I read a post before where either you or Lloyd mentioned about 10% more cfm out of the 561's in stock form.
Anywhooo, Bret I'll be contacting you later this week or early next week to order my supporting parts.
Anywhooo, Bret I'll be contacting you later this week or early next week to order my supporting parts.
#5
Re: Side by side image of 643 vs. 561 castings inside..
now i see why they say the 643 casting have more room to port. the design is completely different underneath. i can also see how they are lighter.
#6
Re: Side by side image of 643 vs. 561 castings inside..
Well I wasn't really posting it as new information, I thought I'd let people see 'em side by side if they had not gotten the chance to yet
I hadn't run into a pic post of them side by side, I'm well aware of the search feature and use it daily
I hadn't run into a pic post of them side by side, I'm well aware of the search feature and use it daily
#9
Re: Side by side image of 643 vs. 561 castings inside..
yeah i knew there was a light weight casting now im wondering you know people have claimed the aluminum LT1 head combustion chambers are 54 cc and other people said they are 58cc i have a set of 643 and before anywork was done they were 54cc im wondering if the 561 castings are 58cc's and thats where people are getting that # from hmmmm???
#10
Re: Side by side image of 643 vs. 561 castings inside..
No they are all 54cc.
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret
#11
Re: Side by side image of 643 vs. 561 castings inside..
So how much more flow are the 643s capable of over the 561s?
Mine are 561s and I thought they turned out nice:
http://web.camaross.com/forums/showt...highlight=Flow
Mine are 561s and I thought they turned out nice:
http://web.camaross.com/forums/showt...highlight=Flow
Last edited by Colin91Z; 02-09-2006 at 12:27 PM.
#12
Re: Side by side image of 643 vs. 561 castings inside..
The 561's flow less ported because they have less material in the areas where taking material out helps flow. I've seen 275-285 out of the 643's
Last edited by Injuneer; 06-18-2018 at 03:08 PM. Reason: CORRECTED PER POST #13
#15
Re: Side by side image of 643 vs. 561 castings inside..
Was just making sure. Lightly read the thread, had to go back through and actually make my few leftover brain cells work for their keep to be sure.