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Posted by: moggy Jun 6 2012, 04:02 PM

As some of you may know I rally a 914 over here in the UK. Mainly against Ford Escorts. Now I always knew that I was down 50bhp to the Escorts but I always thought I was lighter. At the previous rally my car, along with all other competitors, were weighed. My car came in 1010kg, with a full tank of fuel, driver and co-drivr were not in th car. The Escorts were all about the same.

So..... how do some of you guys get so light?

Here's what I've already done to save weight:

Lexan windows, side and back
F/glass boot and bonnet
All grill engine lid
Removed heat shield above exhaust
Stripped out interior including all sound deadening and tar
Late doors but with the crash bar cut out.

Here's what is fighting against the weight savings:

Skid plates front and rear
Front oil cooler and oil lines to it.
Roll cage
Engmann long kit
CFR rear suspension mount reinforcement kit

So.... alot of you guys have the additional weight of the above e.g. rollcage, rear suspension reinforcements etc. How do you get the car below 1000kg? what am I missing???

Posted by: mepstein Jun 6 2012, 04:18 PM

I don't think you can go a whole lot lower than what you have. At least not without BIG $. You said the escorts all weigh about the same. What do they weigh? Can you go faster by improving the handling, braking, ect? Better tires, trans with different gearing, limited slip, lighter wheels? Pro driving school? New engine from Jake?

Posted by: moggy Jun 6 2012, 04:25 PM

Same as me, 1000kg-1100kg

Posted by: Rand Jun 6 2012, 04:35 PM

So, your weight is the same, but you are down 50HP?
And you are running Raby?
And they are running water cooling?
Hmmm.

Raby's engines are the best. But sounds like more power to displacement is needed. And while water adds weight, the cooling efficiency more than makes up for it.


I'm thinking Moggy needs a kick ass engine. What shall it be?

Posted by: moggy Jun 6 2012, 04:42 PM

Raby engine - check
Trans with gearing designed to engine - check
LSD - check
Lighter wheels - check
Pro-driving school - check (in fact they said that there's no way I can drive the car any faster than I am and the reason why I'm running a few seconds slower per mile is all due to the power I'm losing to the big Escorts)

Before anyone suggests....

Metal bumpers are a must due to the little bumps and scrapes (tried f/g and lasted less than a day)
Battery is standard and already ordered a dry-cell, lightweight version but that should only save me 5-6kgs

Posted by: SirAndy Jun 6 2012, 04:49 PM

Dunno about that. My car weights in below 2000 Amurican pounds (with gas but without driver) and it's still street-legal and has a cage.

2000 lb = 907.184 kg

Posted by: Rand Jun 6 2012, 04:53 PM

Reinforcing for dirt rally has to add weight, no? Seems a bit of a different animal to me.

I heard power differences and same weights as competitors. I think it's going to take more power to be competitive. An old air-cooled engine, even with the latest developments, isn't in the same league. As much as I love these air cooled engines, I just don't think they can compete with the modern racers.

Posted by: moggy Jun 6 2012, 05:04 PM

Believe me Rand, more power is in the pipeline

Just want to make sure I'm not missing free horsepower by shedding some weight from somewhere I've overlooked.

Posted by: moggy Jun 6 2012, 05:07 PM

So, what have you got (or not, as the case maybe) that I haven't?

I can't believe that the skid plates (front and back), inner long reinforcement kit and rear suspension mount reinforcement kit all add up to 100kg.... or maybe they do

Posted by: Rand Jun 6 2012, 05:09 PM

I can't wait to see what you do. I just can't imagine you shedding much weight and still keeping her strong enough when you consider what those competitors have been doing. I'm amazed you are at the same weight.

We are rooting for you big time!!!!!!!!!

Posted by: moggy Jun 6 2012, 05:20 PM

Thanks Rand. The next round of the British Historic Championship is in a few days time, let's hope I keep it on the dirt and out of the ditches :-)

Posted by: SirAndy Jun 6 2012, 05:32 PM

Good question.

The Light:
- Started with an early tub (70)
- Stripped all the sound proofing tar
- FG flares and bumpers and rockers
- CF dash
- No backpad
- No carpet
- Early doors
- GT engine lid
- Light wheels and brake calipers

The Heavy:
- Rollcage
- Oil lines & tank and front mounted cooler
- /6 engine

Posted by: mepstein Jun 6 2012, 05:53 PM

That is a pretty amazing weight for a 3.6 six with a cage in a street car.

Posted by: Randal Jun 6 2012, 10:07 PM

Here is what I did:

The base weight of my car is 1682 with the cage and 21/2 gallons of gas. Now that much gas wouldn't be good for a rally, but works great for an autox, hill climb or a 5 minute enduro. I have a 5 gallon tank, which saved a bunch of weight.

I have a complete cage setup, front to back so that adds at least 100lbs.

You ought to consider doing the roof thing that Bill Charron did. He used CF and glued the front and back together. Lost a bunch of weight and made the car super stiff.

I used both a CF trunk and hood.

Cut everything out of the trunk floor.

Stripped out all the caulking in the rear

I'm running the same Chris Foley reinforced trailing arms as you, except I have bearings everywhere.

No rear bar as IMHO 914's don't need one.

Running cookie cutters which are only 15lbs each.

Running a light weight battery, i.e., about 12 lbs.

Cut everything out of the doors.

Cut out the headlight sheet metal and lost the headlight motors, etc., but guessing you need those for night rally.

Using Kirkey seat (light) and only running one, but you'll need two.

No windshield, windows or rear targa window. Can you use the plastic windows in rally?

Not running a engine cover.

Fiberglass bumpers and flares all around

My motor is a Raby configuration, but running fuel injection - puts out 185hp / 185 ft lbs (6K) at the rear wheels. You would like this motor!

Oh I run a big oil cooler up front and SS braided lines back to the external oil pump.

Posted by: J P Stein Jun 6 2012, 10:08 PM

1720 +/-20........with a 6. front cooler, & cage. A similar 4 should be 100+ lighter.

If you want to get serious about this race car stuff you have to be willing to give
the niceties.
Sit down and figure what is required by your rules. If it ain't REQUIRED, shit can it.
No torsion bars (or their brackets) for the lids, The lid springs up front, all that air ducting, motor, dash, wiring, switches. instruments. GUTTED doors....half inch perimeter on the inside sheet metal (figure out some kinda slide mechanism to raise & lower). 12 lb battery.

Go over the car with a fine toothed comb.....& be ruthless.

With added another 100lbs (or less) I could have been street legal.


Attached image(s)

Posted by: Randal Jun 6 2012, 10:14 PM

Hey JP... come on down to Cascade Lakes this weekend and burn up some fuel and tires with me...

Posted by: grantsfo Jun 7 2012, 04:35 AM

Do you have pictures of the car? What kind of class restrictions do you have?

Focus on rotating weight first. Lighter flywheel and clutch, lighter brake rotors, lighter wheels ( there are options such as Jongblode that will get you to 10 lbs a wheel. Even tire choice is critical.

Big savings in going to CF hoods, bumpers, bumpers are critical piece to change. Lose valances, change to cf or fiberglass rockerpanels.

Lose cooling tins around motor, header choice is critical, yes cut the muffler heat shield out, choice of motor mounts can impact weight, engine compartment lid can go away or be replaced with lighter material atta minimum pin the engine lid and lose heavy metal spring rods, lightweight exhuast system,

Pull all tar off floors, remove back panel, remove underside of dash, pull all metal from dash, lose all fan motors and ducting, don't forget to lose all heater elements from motor into the car

Lightweight shift rod, convert to lightweight coilover setup both front and back,

Lose charcoal canister by fuel tank, go to fuel cell, do you need headlights? Consider removing motors and making lights manual if you can do without lights remove them.
Rear window to plexiglass.

Gut doors or even go to door skins, lose parking brake system, lightweight battery is a must, remove heavy stock battery tray if it's still there and locate battery lower and towards front of car.

Remember to try to keep weight balance towards fron of car. 914s are already too rear weight biased

Posted by: ChrisNPDrider Jun 7 2012, 01:37 PM

go to fiberglass door skins and kevlar sheet for skid-plate
what top?
The OEM fiberglass top is pretty light, but a carbon or fiberglass skin will be lighter up top where it is important
Clean out the 10kg of dirt trapped behind your rocker panels!

Posted by: brant Jun 7 2012, 09:42 PM

It does seem a little heavy

I run all metal rockers, hoods, fenders, all of the trunk floors intact, etc and can beat that weight with a -6 installed

you can shave 10lbs from a stock top with elbow grease and only the cost of a few dzus fasteners.... another 50+ from stock doors by gutting the frame etc...

I took a metal car (only fiberglass bumpers) to 1826 wet. It has a windshield, and almost 5 gallons of oil in it. I guestimate that I could take 220-230lbs from my car if I cut everything and went with all glass and a 4 banger.

take pictues for us
I do believe the early chassis are 100 to 200lbs lighter

Posted by: moggy Jun 8 2012, 05:43 AM

Thanks guys, this is a really useful discussion for me.

I need to take some more detailed photos for you to pour over but this is what I have at the moment:











Rocker panels are metal as f/g couldn't cope with the stones getting thrown at them. They only lasted one rally at a time. No dirt underneath them.

I can't use kevlar skid plates due to regulations. However I think they are too thick so there's an opportunity here for shaving some weight. Also, I'm thinking a lighter, smaller version for tarmac events.

Even though I've cut the crash bar (or as much of it as I could get to with the grinder) I still think the late model doors are heavier. Maybe some more I can shave out of this area.

In general, your cars definetly seem lighter.

I also forgot to mention, added weight:

Front ARB

Plumbed in fire extinguisher system.

Hand held fire extinguisher

Posted by: brant Jun 8 2012, 08:58 AM

The window glass (plus windshield and rear window) are killing you

can you run lexan?
I know it won't anylonger be water tight but I'll bet if you gut the doors on both sides, add lexan front and rear you would loose 120lbs.

of course side windows in a rain storm are nice too.....

most of us talking about really light cars have ditched the fresh air system, wiper systems, headlights, etc.....

Posted by: J P Stein Jun 8 2012, 09:43 AM

I can see a ton...well, a bunch of weight to come off.
A 914 Fuch weighs 11 lbs.
This muffler weighs 13 lbs.

That fishing lure called a "stiffening kit" is dead weight with that cage in place......which should really be tied into the strut towers......that will make your suspenders work right.




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Posted by: Andyrew Jun 8 2012, 11:40 AM

What about the doors? You have a cage so you dont need anything but the skin, the hinges, and the latch.

Do you need side windows? Can you get away with a net?

Might be time to get out the hole saw and start drilling holes.. I'd start with the area's behind the bumpers.

Do you need chrome trim? Do you need all of your door seals? Trunk seals, ect ect? What about that fresh air box?

Your muffler like JP said

What about hard mounting the headlights up? Those motors and ect could be 10 lbs by themself..

Posted by: ChrisNPDrider Jun 8 2012, 01:07 PM

word
I would never stomach having headlights up all the time for my cafe racer 914, but for a rally car it is worth considering.
Those motors are metal bricks
The "GT headlight" solution is so expensive if using vendors, but worth a shot if you have in-house fabrication skillz

Posted by: URY914 Jun 8 2012, 01:41 PM

Rookies........

Posted by: stuttgart46 Jun 8 2012, 02:57 PM

Ditch the headlights all together as well as the headlight buckets and use a light bar when you need it. Just my $.02
It is great to see you flogging this car around in rallies.

Posted by: Rand Jun 8 2012, 03:03 PM

But I'd be scared to dirt rally your featheriscious animal.

On that subject, folks let's not forget how Moggy is using this beast.
A lot of the input seems to be coming from ax and track folks (which is all super valuable) but it's a different world getting beat up on the dirt. It has to be brutally strong.

Posted by: moggy Jun 8 2012, 03:44 PM

Brant - I said in my first post I have lexan in all side windows and rear, but the windscreen has to be glass.

Fresh air system is stripped out all apart from the windscreen demister, which is needed.

Posted by: moggy Jun 8 2012, 03:57 PM

That's an old photo - I've already addressed the exhaust. Now on it is a European Racing header and muffler, much much lighter.

Stiffening kit is NOT dead weight in a rally car - believe me!!. GT stiffening kit is not what's on the car, only the rear suspension pickup strengthening, which is needed (ask me how I know ) and the long stiffening kit was put in after it started to crack by the old parking brake handle even with the cage. The car take a lot of grief - it's like Baja racing (which I've also done ) but a little less extreme. Here's some of my take offs







Cage is already tied into rear strut tops. Not allowed to do it at front due to regulations (don't ask.. )

Wheels are also addressed since above photo with Minilites now on the corners (same weight as Fuch)

Posted by: moggy Jun 8 2012, 04:01 PM

Going to re-visit the doors again, and get savage with them.

Rear bumper I'm going to go f/g. Front needs to be metal - for good reason

Contemplating the GT kit for the lights, but fabricate it myself - I'm not paying the high $$ for the kit's I've seen come up now and again (good although they look - it's just I can make that myself.)

Posted by: moggy Jun 8 2012, 04:07 PM

I need the lights for the UK MOT (i.e. to make it street legal). However... light bowls!!! that's a great idea.... they can come out. Nice one

I've got a rally tomorrow morning. Weather is very bad so it's going to be messy and rough Wish me luck... I'll update you all on how I get on - good or bad

Posted by: moggy Jun 8 2012, 04:13 PM

100% right, you're spot on. I've seen some of the track and autoX cars, great that they are for their sport, they would not last one day rallying. No disrepect meant, it's just horses for courses.

Nice KTM - same as my crew chiefs. You know what dirt tastes like.... nice one

Posted by: moggy Jun 8 2012, 04:15 PM

I met a guy who makes aluminium fuel tanks for the rallying guys. You give him your original and a few weeks later he gives you back the equivalent in ally, half the weight - job done. That's another one to add to the list

Posted by: messix Jun 8 2012, 06:34 PM

can you tie the windsheild frame and the cowl into the cage? go to it with a hole saw on any thing that is redundant with the cage. targa bar inner and under side these are many layers of sheet metal. any thing that you have used tubing to renforce cut out or make full of holes.swiss cheese the doors as much as you have time for.john bovey did his and they are stupid light. cut out the front bumper renforcement in the trunk. is there any overlapping sheet metal under the flares that can go?

any time you have some thing off the car ask your self what does this need to work and how can i lighten it up. look at sixnotfour's car his outer door handles are swiss cheeesed!

ounces add up to pounds.....

Posted by: J P Stein Jun 9 2012, 08:27 AM

I'm aware of Moggy's use of the car.
I would wager that my full caged, seam welded, complete AX chassis is stronger than his.
To toss out advice because it comes from folks not in line with your usage is not only arrogant, but stupid. (I would have used "hubris" but you'd have to look that up.)
Rookies.
I'm done. Have a nice day.


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Posted by: moggy Jun 9 2012, 04:57 PM

No decent advice turned away here Afterall you autoX/track guys are the experts here, and I can't ask any guys rallying a 914 for advice as no-one seems to be mad enough Hope that's not me you're accusing of being hubristic but if it is.... I've been called worse, usually by my wife

Picked up some good ideas from all you track and autoX guys so thanks for the pointers. I'll let you all know how much I trim off and where.

Posted by: moggy Jun 10 2012, 02:58 PM

Rally went really well, managed to hold my own against the big Escorts, even managed a first in class on one stage and got within 0.2 seconds of the guy that's currently leading the British championship Happy with that

Here's a little vid of me having a 'moment' yesterday.

http://www.youtube.com/watch?v=BUKOXHeH1bc


https://www.youtube.com/watch?v=BUKOXHeH1bc


Started the car diet this evening. Managed to shave 5 kg off the car so far cutting all sorts of things off and trimming various stuff that was superfluous. Will let you all know how much drops off.

Posted by: URY914 Jun 10 2012, 03:02 PM

Posted by: Randal Jun 10 2012, 06:24 PM

+1 Great driving!

Posted by: Woody Jun 10 2012, 07:59 PM

You have anymore videos?

Posted by: polo classic Jun 11 2012, 04:36 PM

Loose weight, your car needs a diet of drill bits and mill

Inspiration can be found here
http://forums.pelicanparts.com/porsche-911-technical-forum/598867-hot-rod-projekt.html

Posted by: moggy Jun 11 2012, 05:05 PM

Here's another vid for you from a few years back, showing that I can actually go round a corner properly sometimes

http://www.youtube.com/watch?v=-SeD-J6JqYY


https://www.youtube.com/watch?v=-SeD-J6JqYY


The weight is still dropping off. After tonights little stint the scales are weighing in at 10Kg. 6 of those Kg are from a redesign of the spare wheel mount.

Decided tonight that I'm going to have two trims:

Gravel - heavy duty skid plates and metal bumpers.

Tarmac - lighter duty skid plates and f/g bumpers.

At the end I'll weigh the car in both setups and let you know what the results are.

Tomorrow I'm going to start on the dashboard area.

Thanks for the link to that weight obsessed fabrication genius with the 911, nice!! but that's going a little too far for me. Impressive though.

Posted by: moggy Jun 11 2012, 05:07 PM

Anyone know how much those headlight motors weigh each?

Posted by: mepstein Jun 11 2012, 05:28 PM

4.5lbs/each

Posted by: Rand Jun 12 2012, 01:15 AM

Nice JP. Where's your car now? Not that I was referring to you. Take your cranky medicine and get over it.

In case you don't know it, I love ya man and always respect what you have done. (And if you used the "hubris" dart towards me, you obviously don't get me. I'm the farthest from arrogant. I just tease amongst friends now and then. Sorry you didn't catch the vibe. My sense of humor is dry, and this is the Internet, so I understand.)

I was probably poking more at Paul than you and I think he knows it!! While his car wouldn't hold up to Moggy's rally course, it might possibly kick your old car's butt on the AX course!! Then again, Moggy's car wouldn't beat your best AX times, since it is a different animal.

I'm having a nice day. You should too.


Sorry for the diversion Moggy. Can't wait to see what you do next.

Posted by: stuttgart46 Jun 12 2012, 04:58 PM

Congrats on this past weekend's results.
That vid is awesome.

Posted by: J P Stein Jun 12 2012, 06:42 PM

Dude, I LIKE being a grumpy old man.....not to mention I have little choice in the matter.

BTW, Paul drove shitbox for several passes at an AX a few years back. He is the only guy that ever drove it that couldn't beat my best time......it was only a couple tenths but I remind him of that every chance I get. I may be old but I was slow.

Posted by: Rand Jun 12 2012, 08:59 PM

Oh, and you are genius at breaking the quote feature.
Thanks for the story with Paul and the $hitbox. Classic.
Now I would be curious what JP's times would have been like in the lightbox.

Posted by: grantsfo Jun 14 2012, 08:20 PM

Take note of those well engineered mouse ears on his cage. Lol! Thank goodness Brit performed an exorcism and ridded that car of that swamp monster cage. Clearly not much engineering skill went into the beaut!

Posted by: Gunther Jun 15 2012, 08:07 PM

I noticed that no one mentioned that little parachute in the back.
You dont go fast enough to effectively use a rear spoiler.
Cut every little tang and bracket you dont need. replace all steel that you can with aluminium,CF or fiberglass. My 2cents. Good luck

Posted by: moggy Jun 16 2012, 01:30 PM

So how fast do I need to go to 'effectively' use a spoiler?

I've had a few days break from the garage but back in there tomorrow to set on the dash area. Will give an update on the weight that's dropped off and maybe a picture of the metal that's been removed.

Cheers

Moggy

Posted by: SirAndy Jun 16 2012, 08:21 PM

For the rear of a 914 to get light at speed you have to go above at least 110 mph or even more, depending on your setup.

Posted by: Gunther Jun 17 2012, 03:04 PM

The guys At KMW Motorsports did a telemetry test on the back straights of Sebring, an average of 3 to 5mph slower with the spoiler on. @ about 140mph.

Posted by: moggy Jun 17 2012, 03:08 PM

I get over 90 quite often, 110 less often. Although flat out in fifth on tarmac rallies happens now and again Anyhow... I like the look of the kick spoiler, it kinda balances the car, so it stays

I've got up to 11.5kgs that I've dropped off the car.

The front skid plate weighs 9.5kgs and the rear is 22.2kgs, my plan is to re-design these for tarmac rallies at half the weight, giving me a further 15.9kgs saving.

I'm going to go with f/g bumpers front and rear for tarmac events so again a further 12kgs savings over the metal ones.

So all in all that should total up to 39 kgs weight saving (60lbs).

Thanks all for your help

Posted by: Woody Jun 17 2012, 05:35 PM

39 kgs is equal to about 85 pounds. I've been enjoying this thread. Time to get serious with my car.

Posted by: ChrisNPDrider Jun 18 2012, 01:51 PM

WHAT???
Your rear skid plate is 50 lbs!!!!???!?!!
Dude....
Is it integrated into the engine mount bar?
I'm sure that reducing the strength of the rear skid plate is a touchy subject since it is protecting a $6k-$10k USA$(??) TIV motor and likely custom 901 transaxle too.
Show us some pics of that rear anchor, I mean skid plate.
I'm day-dreaming of a protective "cradle" like Brit and other use for mounting Subaru engines in 914s that serves a structural/mounting role but is also rally-bomb-proof.
Great work so far

Posted by: J P Stein Jun 20 2012, 08:44 AM

I'm pretty much out of the game. I stop by occasionally to see what's happening.
I'll miss you guys but not that trolling POS Grant. He's never gotten over me & Brit towing down to the bay area and blowing away him & all his bay area buddies.....on their venue. To him I say

Posted by: ThePaintedMan Jun 20 2012, 09:12 AM

Sorry, I might have missed this.. but what kind of starter do you have on the car? Those things are mighty heavy. Surely there is a lighter, newer option out there. The original ones must be near 20-25lbs.

Posted by: mepstein Jun 20 2012, 09:46 AM

I'm thinking more like 8-10. The whole trans is only 75. There are many articles on 914/6 that Porsche set up for rally's. Go thru them and see what else you can do. Also consider a six if your class allows it.