Project MMPG ~Slow build thread

[erice1984]

Thats what the PO put on it, I had no idea.  please forgive me 

[maxfax]

Where's your battery???


I've always felt that a fair amount of crap blew up into the engine bay though the front of the wheel wells.. 

[erice1984]

battery is in trunk, another change the PO made to the car.

[maxfax]

OKay..  I have the same thing going on..   After I moved it I noticed a lot more crap in the engine bay..  Look down behind the headlight, you should see the hole I'm referring too.. 

 I have an '84 here with plastic liners in the wheel wells I've been planning to swap over to my car, and hopefully help that...   I also have plans for an under engine cover.. Not so much to reduce drag, but to keep the alternator from taking a bath...

[erice1984]

OKay..  I have the same thing going on..   After I moved it I noticed a lot more crap in the engine bay..  Look down behind the headlight, you should see the hole I'm referring too.. 

 I have an '84 here with plastic liners in the wheel wells I've been planning to swap over to my car, and hopefully help that...   I also have plans for an under engine cover.. Not so much to reduce drag, but to keep the alternator from taking a bath...

Very good point.  I should look into that as well.  If you get the liners on your car please share the result.

[Bugsy_malone 666]

looking at the pics though you can see what I mean about taking advantage of the flowing under bodywork, if you were to make the bottom of the car as flat as possible would help. apparently this is why beetle floorpans generally stay pretty clean is due to the amount of flat area under the car.

Something I have noticed under my new mk6 tdi is that they actually fitted flat plastic plates over the floor pan to hide all the gubbins like fuel lines and that and make the bottom of the car as smooth as possible!

Judging by the pictures of clippers on the internet I cant see how adding a clipper kit is going to improve aerodynamics. For a start its going to add weight as its bigger than stock bumpers. for a Second thing its square and boxy where as the stock front bodywork already nicely curves under, I would think the clipper kit actually increases drag.

In my view this is how serious it can be is thinking about how smooth surfaces are, door gaps, things that stick out from the body. I guess I am eager to add good advice on this project as I too want to build something similar (a 1600NA D with a turbo, but NA pump) in a mk3 golf which has slightly better aero dynamics to start with, what I have found is over the years my mpg has gone down through a few things, how I drive and the mods I did for looks on the mk3, like a deeper chin spoiler, hella quadlamps which have less aerodynamics and general stuff like that. Luckily the radiator area of a mk3 is much better designed than the mk1/2 and its fairly well sealed!

[erice1984]

Maybe the clipper kit improves aerodynamics because of how it redirects air around the fenders/wheels and provides better surface up front to attach a skid plate sort of stuff 

I am not quite sure why.  I did notice that Top Gear used the front bumper (I believe) just filled in some holes.

I can't see to find the original top gear article because their website changed, but here are articles on different websites.

http://green.autoblog.com/2009/03/05/top-gear-americas-project-sipster-adds-2003-tdi-engine-to-1981/

http://www.egmcartech.com/2009/03/27/topgearcoms-project-sipster-hits-84-mpg-with-1981-vw-rabbit-for-under-7000/

Also check out http://www.ecomodder.com

This guys claimed 95mpg honda civic

http://ecomodder.com/forum/showthread.php/aerocivic-how-drop-your-cd-0-31-0-a-290.html#post2110

Another eco civic.  This guy made his look much better.

http://ecomodder.com/forum/showthread.php/5th-generation-civic-hatchback-improving-aerodynamics-312.html

[erice1984]

I am going to go out on a limb here and say the possible reason why the clipper kit is used to increase aerodynamics is because the front drops down low enough to redirect air instead of it hitting suspension components (control arms) and wheels.  By adding a belly pan through the entire length (or as much as you can) of the vehicle that would greatly increase air flow and thus reduce drag underneath the vehicle and a front "air dam" wouldn't be as necessary.

Poster "AndrewJ" said,  "So the big idea behind airdams is that they will improve your aerodynamics IF you can improve your Cd without adding to much A. If you tip the balance the other direction, by adding a lot of frontal area without streamlining the shape much then you will actually be hurting your aerodynamics. "

Cd = coefficient of drag
A = Area

Poster "basjoos" said, "In my opinion, an airdam is just a band-aid to use if you have a aerodynamically dirty underside you want to divert air away from. In a max FE application, we're not overly concerned about generating added downforce, which is the other main purpose of an air dam. On my car, I have a totally smooth underside and the only "airdams" on my car are the two air diverters (wheel spoilers) that sit ahead of my front wheels to split the airflow around the wheels. This split airflow is maintained via the double side skirts to the rear wheels and then ideally (future project) should have a small boattail fin behind each rear wheel to reduce its eddy. If you look at the Loremo and the Daihatsu UFEIII, they have airflow splitters in front of each of their front wheels and the UFEIII has a small boattail behind each rear wheel. If you insist on going with an airdam, you can make it a variable height airdam that is deepest in front of each wheel and highest in the section between the wheels. Some airdam-equipped Audis and BMW's go this route."

I think these two things fill in the holes of what we are missing between Bugsy's observations and my reading other peoples stuff.

[dodger21]

Sorry to bring this back on topic.... 

IL Roads-1, Subframe-0....



2 things are happening this week. 1, Thursday I am picking up a fresh subframe from a guy I have bought some parts from for $40. Great guy!

2, getting a 1995 Honda Accord to eventually replace the Crown Vic, as soon as this car gets done.

[dodger21]

It has been awhile but I finally started tearing the car apart.

Here is what it looks like:

Just jumping in and forgot I wanted to take pics! 


2 hours later


Now this had me marveling at the ingenuity of the Germans. As I was unbolting the axle flanges (?) from the tranny, I was mentally cussing at myself as to how I was gonna get the exhaust off. Being from American muscle, all the down pipes are bolted together and usually rusted to the point where we need to cut it off. It was to my surprise that 2 large pieces of spring steel held it on! WOOT!


Now, I am gonna do a "soft" rebuild. New gaskets, hoses, general maintenance. Gasket match the intake and exhaust, add a 2.5" manifold and downpipe. New 2.5" exhaust, wire tuck, OEM+ bay.

[macka]

There are more spots for dirt to hide then a soldier has pockets in these engine bays. Take your time and clean them out, so rust can't build up in them.

[dodger21]

Mind to tell me where the big ones are so I can take care of the problems?

[dodger21]

Thought I posted this Friday night but oh well...

Got some work done today. This is the reason I yanked everything to begin with....



Driver side (the ailing side) is on the right...



Somethings I found when I took the sub frame out:



Torn drivers side steering boot



Passengers side has been rewelded. Screw driver went right through it next to a weld. 



Passenger side strut fell out in 3 pieces, strut and body, spring, bearing(s).

Anyone want to help me here? There are 2 brake lines going to the rear brakes. I thought (never checked) these cars had a valve on the rear beam? 



And every build is not without carnage



Drivers side front sub frame bolt. 

As it now sits. Saturday [never happened. I spent time with my brother and his mk4 TDI] I am pulling more out of the engine bay, pulling the existing harness, getting the newer harness out of the car, and matching up everything to lengthen the harness for a wire tuck. 

[Bugsy_malone 666]

That sub frame is kippered! Looks like you got a fair old job there before you start on the fuel economy, just getting it safe.

As for the master cylinder, maybe its the early ones that had bias valves to reduce pressure to the rear, mk1s deffo had them, not so sure if all mk2s had them, mk3s definately had an axle mounted compensation valve that moves as you load it up.

Looks like you will have your work cut out on this build.

[dodger21]

Well, FWIW, this Golf is a 85 with a build date of 12/84.