Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now

Reply  Post New Thread
Submit Tools LinkBack Thread Tools
Old 03-16-2009, 11:25 PM   #1 (permalink)
Driving the TurboWeasel
Join Date: Mar 2009
Location: Steuben County, NY
Posts: 459
Thanks: 14
Thanked 18 Times in 17 Posts
Better Port-Matching?

On an upcoming maintenance, I have the chance to better match the ports in the lower intake manifold to the heads of my 3800 Series II (L36) powered LeSabre. The ports in the manifold as cast from the factory are terribly formed and much smaller than the ports in the heads. The goal would be to better match the port sizes. The manifold ports would still be smaller than the head ports, and better matching the shape of the ports in the heads.

Yay or nay?

2012 Chevrolet Cruze Eco 6MT
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

Old 03-17-2009, 08:12 AM   #2 (permalink)
Custom User Title
Join Date: Jul 2008
Location: Bozeman, MT
Posts: 248

Daily Driver - '02 Pontiac Grand Prix SE
90 day: 18.45 mpg (US)
Thanks: 1
Thanked 6 Times in 5 Posts
yeay. no point in introducing restrictions on the intake. If the engine doesn't have to work as hard to pump air in, why make it?
  Reply With Quote
Old 03-17-2009, 08:35 AM   #3 (permalink)
Daox's Avatar
Join Date: Dec 2007
Location: Germantown, WI
Posts: 11,182

CM400E - '81 Honda CM400E
90 day: 51.49 mpg (US)

Daox's Grey Prius - '04 Toyota Prius
Team Toyota
90 day: 49.53 mpg (US)

Daox's Insight - '00 Honda Insight
90 day: 64.33 mpg (US)

Swarthy - '14 Mitsubishi Mirage DE
90 day: 56.69 mpg (US)
Thanks: 2,482
Thanked 2,550 Times in 1,537 Posts
Nay. Unless the ports have some horrible flashing or something that creates an easily notable obstruction in them, the smaller port size is going to give better low rpm torque. Since we drive at lower rpms more often this leads to better FE. At low rpm, the small ports are not going to create a restriction at all.
Current project: A better alternator delete
  Reply With Quote
Old 03-17-2009, 01:03 PM   #4 (permalink)
Driving the TurboWeasel
Join Date: Mar 2009
Location: Steuben County, NY
Posts: 459
Thanks: 14
Thanked 18 Times in 17 Posts
Thanks! One less thing to worry about when the top of the motor is ripped off.
2012 Chevrolet Cruze Eco 6MT
  Reply With Quote
Old 03-18-2009, 02:22 AM   #5 (permalink)
EcoModding Apprentice
Bicycle Bob's Avatar
Join Date: May 2008
Location: N. Saskatchewan, CA
Posts: 1,728

Appliance White - '93 Geo Metro 4-Dr. Auto
Last 3: 42.35 mpg (US)

Stealth RV - '91 Chevy Sprint Base
Thanks: 89
Thanked 424 Times in 298 Posts
It would only make a difference with the throttle wide open. So, anybody out there with a CVT and an open-loop override, and probably Fiat's Multi-Lift valve system, don't be put off the idea of improving the intake manifold. It's a good idea.

  Reply With Quote
Reply  Post New Thread

Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to Find your OBDII Port Arminius Instrumentation 4 08-13-2009 11:07 AM
is this an obd2 port? modmonster Instrumentation 5 08-20-2008 11:14 PM
Find your OBDII port the easy way NoCO2 Instrumentation 1 05-28-2008 06:17 PM
OBD-II port (how to run 2 gauges on one port) thebrad Instrumentation 14 04-08-2008 11:10 PM
News: first "kite assisted" cargo ship on commercial run left port on the weekend MetroMPG General Efficiency Discussion 1 01-22-2008 06:48 PM

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com