CFM on a 170 OHV engine?

[54-61-62]

Anybody have an idea on how many CFM's a stock 170 OHV draws through the intake?

Thanks

[mbstude]

Not enough. [)]

Matthew Burnette
'59 Scotsman
'63 Daytona
Hazlehurst, GA

Cruising the Proving Ground Test Track

[Dick Steinkamp]

Here's a calculator for you...

http://www.4secondsflat.com/Carb_CFM_Calculator.html

At 5,000 RPM and 85% volumetric efficiency, it draws about 210 CFM. About 190 CFM at 4500.

[Alan]

Total c.i.d. divided by 2. Then divided by 1728. Multiplied by engine rpm gives you raw CFM. Raw CFM X volumetric efficiency = actual CFM.
Or 170 / 2 = 85 / 1728 = .0492 X 5000 = 246 raw CFM @ 5000 X .85 = 209.1
You should use at least a 220 CFM carb.

[54-61-62]

quote:Originally posted by Dick Steinkamp

Here's a calculator for you...

http://www.4secondsflat.com/Carb_CFM_Calculator.html

At 5,000 RPM and 85% volumetric efficiency, it draws about 210 CFM. About 190 CFM at 4500.

I'd be scared to try to run a OHV six at 5k RPM!

I think I found a suitable carb, it seems to work. Once I get the bugs figured out I'll post a tech thread on how/what/where.

[Tom Bredehoft]

While I'm waiting I'm toying with a Stromberg "backdraft'.

I don't like winding my flathead much beyond 4,000.

[img=left]http://www.alink.com/personal/tbredehoft/Bothcars.jpg[/img=left]
Tom Bredehoft
'53 Commander Coupe
'60 Lark VI
'05 Legacy Ltd Wagon
All three Indiana built OD cars