Stock Rochester 220 and the "bored out" modifications
Thread Starter
Member
Joined: Jun 2006
Posts: 307
Likes: 2
From: Troy, MI
Car: 1988 IROC-Z TBI
Engine: L04.3 = 305-310-336
Transmission: TH-700R4
Axle/Gears: 10-bolt, 3.42 posi
Stock Rochester 220 and the "bored out" modifications
...just out of interest.
A guy at CFM Tech told me that the stock Rochester 220 flows 490 cfm with the injectors in place. He also said that the modified 220s, with 1 13/16" bores, flow 600 cfm and 620 cfm with an injector pod spacer. That's at 1.5 inHg.
Sounds reasonable, since the 1 13/16" bores have a 15 percent greater area than stock and the ridge at the top of the bores are machined down.
A guy at CFM Tech told me that the stock Rochester 220 flows 490 cfm with the injectors in place. He also said that the modified 220s, with 1 13/16" bores, flow 600 cfm and 620 cfm with an injector pod spacer. That's at 1.5 inHg.
Sounds reasonable, since the 1 13/16" bores have a 15 percent greater area than stock and the ridge at the top of the bores are machined down.
Thread
Thread Starter
Forum
Replies
Last Post
Genopsyde
Engine/Drivetrain/Suspension Parts for Sale
3
Oct 7, 2015 08:35 PM
NinjaNife
Tech / General Engine
27
Aug 23, 2015 11:49 AM
