1997 VW Golf - Progression of Modifications and Results

[dfeldt91]

Originally Posted by GreenHornet

Yup that would be me

I may be interested in the rear lights, grille, front lights and hood. I want to put a golf front end back on my "Jetta" golf.

Also, what is the metal block that is bolted between the engine mounts in the second photo? I left it off because it seemed to have no purpose and my friend lost the bolts when we did the clutch. I'm talking about the other CL ad withthe MK3 being parted.

[dfeldt91]

I bought some corrugated plastic the other day to make some rear wheel well covers and a front end belly pan. Monday I will receive some new "Tuner style" lug bolts for the new wheels as the VW bolts are too wide at the collar for my one inch larger tires/rims. The new rims are aluminum instead of steel so they stick out further and take up more of the wheel well gap although they have large holes in between spokes that will need to be covered.

As far as the grill block goes......I am contemplating using plastic or expanding foam to fill in the grille and give it a more finished look. I'm also going to have to fill in the lower bumper opening for the dummy fog lights and the lower radiator.

I got coilovers in the mail and am excited to put them on when I have time and help. Should make for a much cleaner airflow from the wheel wells, especially when used in conjunction with covers and whatnot. I'm thinking low enough to just barely be tucking in the front but not so much that is hinders the ability to turn.

I should have a Bluetooth engine scanner in the mail tomorrow.....hopefully....Let's just say Amazon Prime failed me big time and it has been a whole week now with the scanner being shipped back and forth from two postal locations. It's quite nice to get the same updates over and over multiple times daily for a week....but seriously, when will it leave Federal Way, WA?? lolol. I purchased a good OBD2 app so I can track fuel economy, engine load, RPM, whether or not the fuel is being used when coasting in gear(Classic "more gas in gear or in neutral?" question). I coast in neutral quite often when it isn't a good time for EOC because I thought it was using less gas but a lot of people tell me it is better to leave it in gear and it will shut off the fuel until it reaches somewhere around a few hundred RPMs over idle to keep the car from needing to be restarted at a stop.


I'm starting to have a lot more time with the holiday season since I work from home and want to take time off so I will start documenting with photos and do some actual testing once my covers and wheels are on. I've also decided to do a partial kammback(sp?).

I was at 27MPG before the modifications with my normal driving. With a bit of coasting in neutral mixed with EOC when possible and general good driving techniques I am at 31MPG(6.45% over EPA). Now that I am starting to ecomod the Golf I am hoping to get 37MPG with the grille block, front belly pan and rear wheel covers. 37MPG would be a 21.6% increase over EPA.

Might not sound like a lot but at 14 gallons of fuel per fill up that comes out to $8 in savings.

[deejaaa]

yep, it adds up quick when you don't spend a lot to mod.
my latest grille block has a fiberglass covering. I started with a badgeless grille. the emblem makes it hard to get it smooth.
diesel might not be a good solution. they need to get to operating temp or they will get clogged intakes and sticky vanes.
I can get great mileage when I hit the freeway but suffers tremendously when I have to drive city.
like the project.

[dfeldt91]

I have the molded in badge so I will probably order a badgeless or pick up a used one for $30 off CL then use the foam and sand it down so it looks good. Fiberglass is a bit out of my area of expertise.

I wish this rain would stop, it has been rainy with high winds and lightning the past two days on and off.

[TedV]

Originally Posted by dfeldt91

Also, what is the metal block that is bolted between the engine mounts in the second photo?

It is a chunk of weight to tune out some vibration in the subframe that holds the steering rack. With it off you may notice a little more engine vibration in the steering wheel.

Originally Posted by deejaaa

diesel might not be a good solution. they need to get to operating temp or they will get clogged intakes and sticky vanes.

You can do an adaptation within factory parameters to minimize how much the EGR recirculates to cut down on the soot clogging the intake. A good working thermostat, coolant heater glowplugs and/or an add on coolant heater to have the coolant warm before you start will also cut down on the soot clogging. The less coal you roll at cruise, the less it will clog. People using the TDi's off road have completely cut out the EGR system.

The VNT turbo on the Mk4 are the vanes that might get stuck. Floor the car and work it once a day and you shouldn't have a problem. Waste gate style turbo of the MK3 doesn't have the sticking issue.

If you are thinking of doing a diesel swap, take a look on Freds TDI club forum https://www.tdiclub.com/ It would be cheaper and easier to just buy a running TDi manual, NOT AN AUTOMATIC!! lol

Good luck with the mods, they do add up

[freebeard]

I wish this rain would stop, it has been rainy with high winds and lightning the past two days on and off.

Learn to like it. Not to leads to depression and madness.

They call the month May because it 'may' be nice again.

[dfeldt91]

I had a bunch of free time and a full tank of fuel this afternoon so I figured I would go on a 140 mile trip up the interstate. and back home to see what kind of MPG I'm getting with the new engine scanner allowing me to watch my fuel economy. Using some rather unsafe techniques I was able to go from 29 MPG highway EPA to 47.5 MPG actual with 10 miles of city driving included.

These are the things I did to get 47.5 MPG:

• Use scanner with Torque app to watch instant and average MPG
• Chose a slow moving vehicle to follow (52 mph semi-truck)
• Drafted a car length and a half behind
• Chose gears that gave the best fuel economy(Not fifth all the time as I figured)
• DRL off 50%(until it got dark)
• Turned music down
• Emptied the extra set of wheels/tires and parts from the Golf
• Tire pressure at 45 PSI

I think the best thing you can do to get better gas mileage would be to buy the Bluetooth scanner on Amazon/Ebay/whatever and download the Torque app. Not only does it tell you what is wrong with your vehicle but it can clear codes, tell you your engine specs, FUEL ECONOMY, best shift points for economy, etc.

The next best thing every economical driver should do is choose a slow vehicle and draft it. When I was about 5 or 6 car lengths behind the semi I was still getting 6 MPG higher than my usual so it is not necessary to follow at an unsafe proximity like I did to get better MPG..

I'm excited to get into the modding aspect of this to have a more aerodynamic car to coast longer while engine is off and use less fuel to get to speed.

[paulgato]

I read your thread with interest. I have a 2002 Mk4 Golf estate I've modded a bit for mpg here in the UK. Mine is a 1.9 TDi diesel. I wan't quite sure but it seems yours is probably a petrol (gas) engine...?

Still, the basic car will have some similarities, diesel or not.

I think you're entirely right to prioritise simply making sure all mechanical faults are corrected. After I bought the vehicle I found significant mpg gains from changing a thermostat, changing an alternator, replacing worn suspension bushes, getting wheels accurately aligned (zero toe-in works well and is actually what VW specify), changing a temperature sensor, and renewing the manual transmission oil.

(The alternator was replaced because it failed, but also it turned out had a stuck freewheel pulley. The new alternator had an operating (freewheeling) pulley which suddenly enabled the car to run smoothly at idle speed (800rpm) enabling me to drive in 5th gear at 27mph or 4th gear at 20mph, thus boosting my in-town mpg enormously!)

(VW say you never need to renew the gear (transmission) oil but after 150,000 miles I changed it, added a small tube of Molyslip, and I could feel the difference instantly. Probably gained 2 mpg from that.)

So yes, step one is to make sure the car is running as designed.

Next simple mod is tyre pressure. I just pumped them up to the max sidewall pressure marked on the tyres, which was 51psi. I found it drove WAY better like that - didn't wallow through corners any more - and mpg was significantly up. It makes hitting potholes a bit alarming, but I drive so slowly that I can generally avoid them. I've run tyres through their entire life like that and there's no (zero) signs of uneven tyre wear. I think that thing of tyres wearing excessively down the centre line when over-inflated only applied to older, non-steel-belted tyres.

I always meant to do some aero mods, although I am uncomfortable about anything which draws attention, so I've kept both wing mirrors and wouldn't contemplate a boat tail, etc. I have a (stock) under-engine tray, and always intended (still might) to fit a rear undertray, mostly to cover that horrible scoop-shaped gap just between the rear bumper (fender) and the spare wheel well.

What I have done is to fit an engine pre-heater and an extra battery and charger, etc, so I normally don't use the alternator, and always start my journey with a 70% warmed-up engine. That 'plug-in mod' saves me about 15% on fuel overall, but it wasn't easy or cheap, and it does shorten the life of batteries to have them discharging daily like that, so I don't know if I can really recommend it, but I have no regrets myself.

I did remove the A/C compressor, a) because I never used it and it is surprisingly heavy, and b) because I had to mess about with the alternator a lot to get it to work and I got fed of struggling with the serpentine belt all the time. I dumped the A/C compressor and got a belt for the version of the car with no A/C. Whew!

This probably only applies to the VW diesel engines, but they overcool massively, and even in the mild English climate absolutely REQUIRE an aggressive grille block if they are to run at the designed temperature over the winter. You will have discovered with your Torque app that the dash temperature needle bears little relation to the actual temperature. Mine is designed to show exactly 90 degrees C (dead centre) at any temp between 75 and 107 C.

As for driving style, I've found that the Golf is relatively heavy and needs to be driven 'like a boat' for maximum mpg. I.e. assume you have no brakes. Pick a speed that you can maintain safely both on the straights and on the bends and stick to it.

Hope you don't mind the unasked-for advice. Take from it what helps and ignore the rest.

I've kind of lost interest in eco-modding as such. It's been an interesting exercise. I had wanted to get up to 100mpg (Imperial) but never managed it. My best ever was a measured 89.9mpg average on one tank of fuel over about 1400 miles. (As per fuelly.com stats) I could certainly get well over 100mpg on a long slow run in good conditions, but not in 'real world' driving over a tank-full. I came to the conclusion that the main obstacles to fuel efficiency are political rather than technical, so I joined the Green Party and stood for office last May. Didn't get elected. Will try again this May, as local govt re-organisation means we have elections again this year.

I reckon that if maximum speed limits were reduced to 50mph and it was known that they would never rise again then manufacturers would design for that speed. Smaller, lighter cars and engines small enough to be running at about 70% load at 50mph would become the norm. Cheap and simple electric cars would suddenly become much more viable if highway speeds were reduced to 50mph, etc. etc. Cycling would be safer if cars were smaller and slower, so more people would leave the car at home more often and cycle. Other advantages: wildlife would be squashed less with cars going at 50mph. (Wild animals have evolved to cope with things moving at around that speed, but often get confused with traffic moving at 60 or 70, especially at night.) Oh, and aquaplaning is physically impossible below 50mph even with completely bald tyres. That one simple (political) change in maximum speed limit could, I reckon, cut overall vehicle emissions by 50% after ten years.

Anyways, good luck with it all.

[dfeldt91]

PaulGato: Thanks for taking the time to share all the information! I appreciate it greatly.

You are correct in guessing my vehicle is petrol/gas. I have been replacing parts and finally figured out the issue with the cold starts: rotor cap(it is a petrol thing :P ). The car now has a bit more power with a good rotor cap. I also replaced the coil and fuel pressure regulator which I thought might have been the issue before the cap.

I definitely need an alignment now after doing the clutch. The car has a very slight left pull. Also I think the wheels I got are bent as the steering wheel will vibrate and wobble back and forth just slightly. Might possibly be related to not having hub centric rings.

I am going to buy an AC bypass pulley bracket and remove my AC completely as the previous owner had cut the hoses for some reason. I never use it anyways, even if it is hot. I am going to use the AC button in the dash as my injector cut off switch to save fuel when coasting and not have a hideous switch drilled into the dash somewhere.

I also want to do a power steering delete or at least route the tubing back into itself instead of into the steering rack. That should net a good increase in mpg.

I run my tires at 45 PSI although it was warm then and it is freezing now so I need to reinflate them to max PSI. I do get the harsh jolt from speed bumps and pot holes but I generally just avoid them and don't have an issue.

I thought about getting a block heating unit but I heard it is very hard to install on my engine. I haven't really looked into it but have noticed that MPG is significantly lower when cold then warm according to the Torque app.

I have also noticed my engine overcools to the point where it barely moves the needle. Like it shows still cold and is on the very first tick. The only time it will reach the central tick where it should be is if I am driving like an idiot when traffic is slow with quick revs and acceleration. I am going to do a grill block with the plastic I purchased a few months back for the job. I'll also put in the under try the same weekend.

I never reach fifth gear with my larger tires in city. I might put my old one inch smaller tires and wheels back on and see if that helps.


Anyhow, I really appreciate you taking the time to write as I am now back in the ecomodding game after a month break.


Side question? Do you happen to know what would cause a squealing noise immediately after starting when trying to turn the wheel? It only happens when turning the wheel and immediately stops if I stop turning the wheel. I only notice it when I am turning out into the street from the curb where parked when cold then doesn't happen again till the next morning.

[dfeldt91]

You definitely need to run for office. Remind me Thursday after I win this 1.5 Billion US dollar Powerball jackpot and I'll come back you with some moolah!