Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   Pelican Parts Forums > Porsche Forums > 911 / 930 Turbo & Super Charging Forum

LinkBack Thread Tools Rate Thread
Thread Post New Thread    Reply
Chain fence eating turbo
Join Date: Dec 2008
Location: Austin, TX
Posts: 8,695
Protomotive tuned factory ECU using 380cc injectors on an '87 C3.2 with 427 whp here. I would go through a tank of gas in about 3-4 days with a round trip of 50 miles a day all highway (was a DD for a couple of months).

Not so great....

Never could calculate actual numbers due to odometer being broke.
Cory - turbo'd '87 C3.2 Guards/Blk, 3.4, 7.5:1 CR P & C's, soon to be 993SS cams and GSXR 750 ITB's fed by 964 intake, Borg-Warner S366 turbo @ 1.4 bar, Treadstone full bay IC, TiAL F46 WG, HKS 1 1/2" BOV, twin 044 pumps, MegaSquirt 2 (v3.57 board) w/EDIS, Tramont wheels (285's rr, 225's frt), Big Reds frt, 993 rr., tower brace, MOMO wheel
Old 03-20-2010, 06:45 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #21 (permalink)
Registered User
Join Date: Jan 2004
Location: Sacramento
Posts: 7,269
Weight and drag seem to be the two most significant parts of fuel economy.

CIS and EFI can both be tuned to run near peak efficiency but it is much easier to achieve a near ideal AFR and ignition settings with EFI.

After that it seems to be about increasing the VE of our motors at off WOT settings.

Off boost compression (up to +10%) and exhaust efficiency seem to be the next variables in line. Twin plugging probably being close behind (up to +4%).

One is going to make more power out of the same amount of fuel with more compression and get more from each gallon.

Reduced back pressure reduces drag on a motor during the exhaust stroke for more power from each gallon.

Twin plugging allows for later ignition during the compression cycle for less resistance being created before TDC and more power from each gallon.

Of course, a motor that puts out 500hp is going to use +/- 100% more fuel at WOT than one making 250hp.

With a CIS 930 the biggest challenge is achieving significantly more timing advance at part load cruse to get the most out of every gallon of fuel. Most run about 25 deg advance on curse. Most modern cars run well into the 30's of advance on curse.

Thus, I suspect our most significant limitations are frontal area, compression ratio, and the stock 930's timing system.

Last edited by 911st; 03-22-2010 at 10:45 PM..
Old 03-22-2010, 10:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #22 (permalink)

Thread Tools
Rate This Thread
Rate This Thread:


All times are GMT -8. The time now is 03:29 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.