The Cal-look Lounge

Cal-look/High Performance => Pure racing => Topic started by: Garrick Clark on July 30, 2018, 14:18:18 pm



Title: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on July 30, 2018, 14:18:18 pm
Hi Guys.
Right so my 67 turbo bug.
I've got to the point were my engine runs good, The box has some strength and it drives relatively good.

I only drive it on the street, But i'm looking for ways to get more excelleration off the lights.

This bug is all steel , all glass,T bars, stripped interior and 2 standard seats with harnesses.

So where  would i spend the money. For a street car only i do wonder if the cost of getting lighter panels is worth the money. I did read that getting the vehicle 10lb less  is 1hp gained, so the price of loosing 100lb to get  10 hp could get expensive and NOT cost effective.

I run at 1 bar boost. I dont see this as a high boost level really
so maybe i've aswered my own question put More boost into it, Im sure this turbo will do 1.5 bar without going pop.




Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Erlend / bug66 on July 30, 2018, 15:27:20 pm
I would want the weight.

More power is ďeasyĒ  ;D


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on July 30, 2018, 16:04:12 pm
Maybe use the Wallace drag race calculator and play around with different power to weight ratios and see what happens to the ET.

Lee


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on July 30, 2018, 16:32:25 pm
Ok Thanks Guys.
My set up has been difficult to get this far. It might be easy (ish) if I had fuel injection , but a single blow through carb is quiet hard, I only no the old school way of doing things. No EC you for me.

I'll have a look at the wallace site.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: richie on July 30, 2018, 18:43:54 pm
More boost/hp wont necessarily equal more acceleration but less weight will and will be more kind to your engine/gearbox etc as well ;)


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on July 30, 2018, 19:37:02 pm
Ok didn't think of it like that.
I'll take to the weigh bridge and get it weighed.
What's your guess on what it weighs now.
All steel.
All glass.
No rear valance or engine lid.
Stripped interior. JUST 2 standard front seats.
T bars on front
Rear discs. (must be double weight of a rear drum set up).
Copy BRM wheels
no spare
Type 4 engine.
Turbo.
No cage.

Thanks.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: richie on July 30, 2018, 20:07:23 pm
Ok didn't think of it like that.
I'll take to the weigh bridge and get it weighed.
What's your guess on what it weighs now.
All steel.
All glass.
No rear valance or engine lid.
Stripped interior. JUST 2 standard front seats.
T bars on front
Rear discs. (must be double weight of a rear drum set up).
Copy BRM wheels
no spare
Type 4 engine.
Turbo.
No cage.

Thanks.

1870lbs with you in it


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: dragvw2180 on July 30, 2018, 20:33:45 pm
The 1966 bug street car I own now weighs 1800 w/o me in it , this is a 2387 turbo car . When I had this engine in my old race car I wanted to pick up some E/T so I removed 125 lbs off the total weight of the car , car went from 6.41 to a 6.35 , bummed me out, LOL . Mike McCarthy


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Erlend / bug66 on July 30, 2018, 22:03:32 pm
More boost/hp wont necessarily equal more acceleration but less weight will and will be more kind to your engine/gearbox etc as well ;)

Any advice on a minimum weight with a car going let's say 140mph? Or doesn't it matter?


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on July 30, 2018, 22:15:35 pm
Mike , this is what I'm worried about, spending money on light weight seats/lexan windows/battery etc , doing hours of work drilling parts etc and not getting a performance increase to match the money/labour effort. I'm not trying to get low times down the strip. I just want to feel  the improvements while street driving. If I chuck a couple more thousand  at it I want to feel it in terms of acceleration. Not interested in top end really.

After spending a couple more thou on light weight panels/seats/windows etc and feeling that the car isn't  quicker I'd be pretty disappointed.
 


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: richie on July 31, 2018, 08:06:30 am
More boost/hp wont necessarily equal more acceleration but less weight will and will be more kind to your engine/gearbox etc as well ;)

Any advice on a minimum weight with a car going let's say 140mph? Or doesn't it matter?

Weight in right place is much more important, but lightest car I know that has gone 8.90s@149mph was 1600lb


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Erlend / bug66 on July 31, 2018, 08:30:53 am
More boost/hp wont necessarily equal more acceleration but less weight will and will be more kind to your engine/gearbox etc as well ;)

Any advice on a minimum weight with a car going let's say 140mph? Or doesn't it matter?

Weight in right place is much more important, but lightest car I know that has gone 8.90s@149mph was 1600lb

Thanks,

Yup, moving weight to balance the car is needed.

1600lbs is 725kg for those of us using a logical measuring system  ;D


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on July 31, 2018, 14:15:47 pm
So who can do or who has the balancing equipment to balance our vee dubs and why is it so important.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: richie on July 31, 2018, 18:59:40 pm
So who can do or who has the balancing equipment to balance our vee dubs and why is it so important.

Typically we add weight to rear of car and easiest place to loose it is from front, so you end up with a tail happy car you cant steer :o

We do our own and have our own scales but any decent road race or rally prep type shop should have access to them, and most drag race chassis shops will have them


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 01, 2018, 19:32:56 pm
Maybe use the Wallace drag race calculator and play around with different power to weight ratios and see what happens to the ET.

Lee

Have you used this? How accurate was it?


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on August 01, 2018, 21:52:38 pm
I have Dave, I found it surprisingly close to my cars best ET

Lee


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 02, 2018, 06:18:09 am
Cool! I have heard about it but have never used it as I donít have any accurate information about my cars weight and power output,etc.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on August 02, 2018, 07:57:03 am
I only used it after I had the oval weighed at the local scrap yard (had to tell them despite appearance I wasn't scrapping it!)
As the original post asked, I then worked out how much quicker the car would go if  I saved a certain weight.
Lee


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 02, 2018, 19:19:48 pm
Just been on the Wallace ET calc.
If i loose 300lb the ET goes down  . 61 of a second.

So from my set up..  loosing 300lb in weight i'd have to change what on my bug. thats alot of weight for very little gain.

Theres probably an amount of hp increase that will beat that. Which 1 is cheaper.

Just waying up my options. I'm only a streeter anyway.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 02, 2018, 20:58:13 pm
Replace the glass windows that will probably be the cheapest/ biggest weight saver.



Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 03, 2018, 10:09:08 am
Ok thanks Dave. So is there anyone on the lounge making window kits for use with standard rubbers.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 03, 2018, 10:13:29 am
Buy a sheet and cut your own. Use your old glass as a template.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: andy198712 on August 03, 2018, 17:08:47 pm
Buy a sheet and cut your own. Use your old glass as a template.

whats it like to cut? tape it and slow saw speed like acrylic or?


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on August 03, 2018, 17:25:59 pm
I'm sure I did mine with a wood blade. Make sure you buy the coated/scratch resistant stuff

Lee


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 03, 2018, 17:36:24 pm
Buy a sheet and cut your own. Use your old glass as a template.

whats it like to cut? tape it and slow saw speed like acrylic or?

Easy, I used a jigsaw, the polycarbonate had a protective film on it so I drew straight on that.

I wouldnít use a wood blade as itís likely to chip, you might get away with using one if itís a reverse cut blade. I think I used a finer toothed metal blade or a progressive blade.

Marguard polycarbonate is the type Lee is referring to.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: andy198712 on August 03, 2018, 18:48:08 pm
Buy a sheet and cut your own. Use your old glass as a template.

whats it like to cut? tape it and slow saw speed like acrylic or?

Easy, I used a jigsaw, the polycarbonate had a protective film on it so I drew straight on that.

I wouldnít use a wood blade as itís likely to chip, you might get away with using one if itís a reverse cut blade. I think I used a finer toothed metal blade or a progressive blade.

Marguard polycarbonate is the type Lee is referring to.

yeah metal blade will be nice with it.
do you use stock seals with it?

looks about the cheapest place on the car to loose weight other then running less fuel and no spare tyre.... and eating less  ;D


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 03, 2018, 18:54:49 pm
I Put some masking tape on the base of my jigsaw too so it doesnít scratch and blow any debris out the way while cutting.

I used the original window rubbers that came with my car, I think marguard polycarbonate comes in 6mm thickness Iím not sure what thickness vw glass is.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on August 03, 2018, 19:26:40 pm
I was sure it was a wood blade   ???

I did do it 10 years ago though..... ;D

Lee


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Neil Davies on August 03, 2018, 20:13:10 pm
Direct Plastics in Sheffield do Margard polycarbonate in various thicknesses. They're used to supplying race car folk too.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 03, 2018, 20:20:44 pm
Nice 1 Neil.
I'll be ringing them next week.
How hard is  rear screen to fit what with it being curved. i take it most people leave the front screen alone.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Neil Davies on August 04, 2018, 08:33:08 am
It's a bit of an arse, not going to lie! Trickiest bit is cutting it down accounting for the double curve. Think I used 4mm in my race car.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: spoolin70 on August 04, 2018, 10:09:02 am
I can't remember the exact details or reasoning Garrick but I thought a plastic/lexan/polycarbonate windscreen was an issue.

Possibly an MOT failure, maybe not road legal etc.

I have polycarbonate rear side windows and at the time thought about front and rear too but this put me off plus the curvature.
Sides are easy as they are nice and flat  ;)

Many years ago I carried 2x fully built doors a short distance and was surprised by their weight. Not totally sold because I like windows that move and working locks haha

Good luck
Darren



Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: leec on August 04, 2018, 10:37:55 am
My oval has passed an mot every year since having lexan all round. I'm sure you could fix lexan in a VW lifter so you could retain an opening window assembly. Lexan 1/4 lights would be cool too  :)


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: DaveN on August 04, 2018, 11:07:12 am
What oval needs a mot :D

Iím not sure on the legality of the windscreen either but I fitted one anyway itís got to be safer than 40 year old glass. I also used it in the driver/passenger doors of my bug.

Itís a bit tricky fitting the front and rear windows 4mm will be easier to bend. Last set I done was for my fiat (6mm)I templated mine with thin card for the curved rear window and the front I had to start again as the old one was smashed


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Neil Davies on August 04, 2018, 16:56:48 pm
As far as I can work out, a polycarb screen is not a fail, but it has to be free from defects, same as a glass screen, and without the coating it scratches REALLY easily!


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: andy198712 on August 04, 2018, 20:19:11 pm
so does this coating just help or actually make it tough? i reckon you could polish it every year or so if it got lots of micro scratching causing hazing


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Neil Davies on August 05, 2018, 07:03:28 am
When I first built Headstraight, I had regular polycarbonate for all the windows except the rear screen - as that was the only unchopped window I left that in glass. After a season or so I replaced the glass with the Margard, and even then it was noticeable how the regular polycarbonate had hazed, but the Margard never did in all the time I had the car.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: hotstreetvw on August 05, 2018, 21:52:19 pm
Less weight or more engine.  Do both.

I built a spreadsheet and listed the items where I thought I could save weight, assigned a weight savings and a cost.  Calculate a $/lb.  start with the lowest $/lb for the biggest bang for your buck.  I got pretty aggressive on both, losing over 200lbs and gaining a bunch of power.  The car went from 13.6s to 11.90s (at altitude)


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: modnrod on August 06, 2018, 01:43:00 am
I had a light '63 for a fun streeter that ran high-15s, the weight was around 1750lbs (800kg) on the street with 1/4 tank.
This gave the little single-carb 1641 about 72rwhp on the Moroso slide.

If I put that same spritely little engine in my heavier-than-stock Super which weighs about 2250lbs (1020kg) same as above, then it becomes a flat-17 sec also-ran.

When the cars are slow is where the weight loss works really well, but the faster they go the less effect it has.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 06, 2018, 20:17:46 pm
Ok .Its looking like my winter project is to go light, ready for next summer. I'll get a starting weight and go from there. Its going to have to be a  bolt off/on kind of thing as the bug is a non welded 67 and in my opinion once you cut the body the value of the vehicle drops significantly. Plus.

I have been reading the weight loss thread and it is a good read.It says i've done this i've done that but what I'd like to see is  some of you PRO guys to put up a step by step how to guide, with the results so me and other novice performance orientated street/strip vee dubbers can use. The way i see it is if we all get quicker the top boys will have to get there thinking caps on to stay at the top and hopefully improve on there own personel best times.

Also a buy your light weight parts from here guide.(uk dealers for ease of purchase).
wings from

battery from

wheels from etc


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 09, 2018, 17:37:42 pm
Anyone no the weight saved on 4 fibre glass wings and a long bonnet from East Coast buggies compared with the original German panels.
Thanks.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Neil Davies on August 09, 2018, 18:05:42 pm
I think Richie weighed those panels on 10 secs for £10k, or maybe in the weight saving thread?


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 10, 2018, 17:40:43 pm
Yeah got it ,thanks.
I see a fibreglass bonnet has a good weight saving to it. The price of 4 fibreglass wings PER lb loss not so good. Mind you if you need wings its worth it. And the flared ones look v cool.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: richie on August 11, 2018, 19:00:20 pm
Guessing you don't run bumpers? we do lightweight blade version and also lightweight running boards

cheers Richie


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on August 11, 2018, 22:23:52 pm
No bumpers Richie. Still got the running boards. So gunna get those off tomorrow.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: fish on September 28, 2018, 02:00:02 am
IMO all that weight saving is a waste of time and money for a street car, stuff like rotational mass, brakes, beam, seats are also where you can save a lot of weight but at what cost?

I would work on the turbo spooling up earlier and getting a better hook up, maybe more aggressive clutch with hydraulic clutch management or anti-shocker.


Title: Re: What's More Cost Effective. Less weight or More engine.
Post by: Garrick Clark on February 11, 2020, 18:07:55 pm
Back on it.
So, plastic 4 performance will make
a Lexan
Rear screen
1/4 windows
door windows
for 280 quid. 50% weight saved
Total weight saved would be....how much.
What do ya think on the weight saved per £ spent