What Size Carb for a mild 360

[Bruceynz]

Hi Guys,

Ok where to start, I bought a LA 360 from the USA to NZ, its come with a holley 870CFM street avenger, I have a holley 650 vac secondary and I have a new 600 Holley arriving next week. I originally bought the holley 600 for my 318 but have gone 360 now. Anyway I get onto summit website it says the 600 should be fine up to 6800rpm with a VE of 85%.

http://www.summitracing.com/expertadviceandnews/calcsandtools/cfm-calculator

My thoughts are the 600 will give low end performance with good air speed, the 870 will is pretty big and might bog but in their day Chrysler put some pretty big spread bore thermoquads on 360s, has anyone ran a 600 on a mild 360 or should I be thinking the 870? or is the 650 where its at?

I would like to run the 600 if I can get away with it, for 2 reasons its new and I know I will have many miles with no problems, my 650 will need a rebuild, it leaks on the fuel tube and the 870 is an unknown been told it works fine.

360 going in the doba

Thanks
Bruce

 

[80mirada]

I ran a 600, a 650, and a 750 on my 360 in my Mirada. It is really going to depend on the cam and rear end. Mine really liked the 750 the best and could have used a little more, but the 600 will run well and pull strong vacuum. Unless you are thinking about returning the 600, I would give each of them a try.

 

[Bruceynz]

The cam is a mystery, Its has a cam, its got double valve springs and doubler roller timing chain, previous owner said it idled ok and had plenty of punch in the 72 charger. I can't return the carb but I could sell it unused which would mean I could get better money than using it if you know how I mean. The carb came from the USA I am in NZ, freight back is a problem. What spec was your cam and what was your rear end ratio, I have a 3.21 8.25" to go in.

 

[80mirada]

I had a 340 cam and a 2.45 8.25". I think I would give the 870 that is on it a try first, hopefully the previous owner tuned it .