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320touring · 08-28-2011, 06:04 PM

318iS Ecomodding project

So after 9000 miles in 6 months, Ive decided that I really should try this ecomodding malarky on the daily driver..

The car is a 1994 BMW 318iS. its a 1800cc 16v 4cyl engine with circa 140bhp.

5 speed manual box (1:1 5th gear) and a 3.45 rear diff

Weight is 1240kg (2750lbs)

Car is completely standard and has returned approx 40.4 MPG(imp) over my time of ownership.

Currently I'm using the following hypermiling tips/tricks:

Tyres at 40PSI

P&G (engine on) using indicated load of 20mpg on the onboard econometer

DFCO using gears to reduce car speed approaching junctions etc

Both myself and my girlfriend use the car regularly- she's pretty good at the hypermiling, and is usually within an mpg or two of myself.

Aims

1. Improve the Car's average MPG from 40.4mpg to 45mpg.
2. Maintain the current level of practicality.
3. Utilise only "Reversible" Mods, so that car can be returned to stock if required.
4. Costs of any modifications must be covered by the savings gained
5. Total Outlay for Modifications should be no more than £250
6. The car must appear almost unchanged visually-Kammbacks etc are a no no with the police/insurance companies.

Here are some pics of the car, along with my proposals

(i'd be grateful if someone could place the "ideal" aero template onto the side view, please)

Side View (rear wing is missing due to me needing to refit it properly)

I've now refitted the wing- but I can see that having no rear wing would be advantageous- fitting a no wing bootlid should resolve this

Front End

Immediate thoughts centre around the Large Lower Grill/upper grill

closely followed by potential for wheel spats/smaller door mirrors

Rear End

Initial investigation suggests not too much to do outwardly here.. however I see potential for improvement by reducing the "parachute " effect of the bumper by sealing the gap from the spare wheel pan to the bumper

Front Wheel Arch/ Alloy wheel shape

These "Bottletop" alloys are an odd design, esentially the curved outer spokes are higher than the centre- meaning the alloy looks like a shallow bowl.

I could see covers working for these- any suggestions as to how to mount them?

Rear Arch

Again I can see potential for spats infront of the rear wheels, and if possible a way to tidy up the rear edge, as it sticks out past the wheel.

additionally, wheel covers could be fitted. I'm not prepared to fit rear arch covers though, as this car is fairly rare in having very solid rear arches- I want to keep it that way

Bonnet(Hood) to Windscreen angle

Any suggestions welcome here-is it worth trying to modify the angle?

Engine Bay Overview

Immediate things that spring to mind are

Top cover to quicken coolant heating
Wing/Slam panel seals to minimise air into the bay

Engine Bay Gap behind grills and Below Radiator

This has lots of potential for improvement:

bellypan to close off the bottom of the bay
Sealing behind headlights
Slam Panel Cover
Internal Grill blocks

Current Air Intake setup

Again, scope for improvement here by fitting a Warm Air Intake ducting air from the exhaust manifold (right rear corner of the bay) to the Air meter.

There's plenty of space infront of the engine to run some tubing- I just hope the air meter can adapt to the lower density warmer air

Other Ideas

Engine bay Weight Saving
Electric Fan Install
Interior Weight Saving
Source Smaller Wing Mirrors
Fit Taller Ratio Diff (3.25/3.15?)
Full length Belly Pan

I'd be interested to hear your suggestions/ideas/observations- please dive right in!

Thanks

08-28-2011, 06:04 PM	#1 (permalink)
320touring Master EcoModder Join Date: Jun 2010 Location: scotland Posts: 1,434 The Mistress - '88 Bmw 320i Touring SE Team m8 Last 3: 27.17 mpg (US) Germany Beadle - '91 Mercedes 300td (estate, N/A) 90 day: 24.63 mpg (US) The Bloodylingo - '05 Citroen Berlingo Multispace Desire 90 day: 39.77 mpg (US) Shanner Scaab - '03 Saab 9-5 estate Vector 90 day: 26.19 mpg (US) Clio 182 - '05 Renault Clio RS 182 182 90 day: 31.73 mpg (US) Thanks: 90 Thanked 95 Times in 79 Posts	BMW 318iS e36 Project- Aiming for 45MPG (imp)-Suggestions Wanted! 318iS Ecomodding project So after 9000 miles in 6 months, Ive decided that I really should try this ecomodding malarky on the daily driver.. The car is a 1994 BMW 318iS. its a 1800cc 16v 4cyl engine with circa 140bhp. 5 speed manual box (1:1 5th gear) and a 3.45 rear diff Weight is 1240kg (2750lbs) Car is completely standard and has returned approx 40.4 MPG(imp) over my time of ownership. Currently I'm using the following hypermiling tips/tricks: Tyres at 40PSI P&G (engine on) using indicated load of 20mpg on the onboard econometer DFCO using gears to reduce car speed approaching junctions etc Both myself and my girlfriend use the car regularly- she's pretty good at the hypermiling, and is usually within an mpg or two of myself. Aims 1. Improve the Car's average MPG from 40.4mpg to 45mpg. 2. Maintain the current level of practicality. 3. Utilise only "Reversible" Mods, so that car can be returned to stock if required. 4. Costs of any modifications must be covered by the savings gained 5. Total Outlay for Modifications should be no more than £250 6. The car must appear almost unchanged visually-Kammbacks etc are a no no with the police/insurance companies. Here are some pics of the car, along with my proposals (i'd be grateful if someone could place the "ideal" aero template onto the side view, please) Side View (rear wing is missing due to me needing to refit it properly) I've now refitted the wing- but I can see that having no rear wing would be advantageous- fitting a no wing bootlid should resolve this Front End Immediate thoughts centre around the Large Lower Grill/upper grill closely followed by potential for wheel spats/smaller door mirrors Rear End Initial investigation suggests not too much to do outwardly here.. however I see potential for improvement by reducing the "parachute " effect of the bumper by sealing the gap from the spare wheel pan to the bumper Front Wheel Arch/ Alloy wheel shape These "Bottletop" alloys are an odd design, esentially the curved outer spokes are higher than the centre- meaning the alloy looks like a shallow bowl. I could see covers working for these- any suggestions as to how to mount them? Rear Arch Again I can see potential for spats infront of the rear wheels, and if possible a way to tidy up the rear edge, as it sticks out past the wheel. additionally, wheel covers could be fitted. I'm not prepared to fit rear arch covers though, as this car is fairly rare in having very solid rear arches- I want to keep it that way Bonnet(Hood) to Windscreen angle Any suggestions welcome here-is it worth trying to modify the angle? Engine Bay Overview Immediate things that spring to mind are Top cover to quicken coolant heating Wing/Slam panel seals to minimise air into the bay Engine Bay Gap behind grills and Below Radiator This has lots of potential for improvement: bellypan to close off the bottom of the bay Sealing behind headlights Slam Panel Cover Internal Grill blocks Current Air Intake setup Again, scope for improvement here by fitting a Warm Air Intake ducting air from the exhaust manifold (right rear corner of the bay) to the Air meter. There's plenty of space infront of the engine to run some tubing- I just hope the air meter can adapt to the lower density warmer air Other Ideas Engine bay Weight Saving Electric Fan Install Interior Weight Saving Source Smaller Wing Mirrors Fit Taller Ratio Diff (3.25/3.15?) Full length Belly Pan I'd be interested to hear your suggestions/ideas/observations- please dive right in! Thanks __________________ My Blog on cars- Fu'Gutty Cars http://fuguttycars.wordpress.com/ US MPG for my Renault Clio 182 --------------------------------------------------- Last edited by 320touring; 09-04-2011 at 07:49 AM..