Weight reduction: Running out of ideas.

[BBShark]

The support for the nose of the car looks like a compromise between what is ideal and what would fit the car. Probably all caused by the open hood taking up the space needed to do it properly (as you describe).

The triangulation of the center brace by the rod is really poor. I question the effectiveness of it in the first place. Also, the nose of the car is notched so that the bumper attaches directly to the bracket and does not really support the nose body work. The corner braces do capture the body between the brace and the bumper but how effectively does that support the nose. Support of the nose appears to be accomplished by the headlight brackets that are mounted directly to the bumper. That is a pretty convoluted system for a support.

I don't have a good answer but I was hoping to use a conical front mounted air filter in between the U shaped center brace. Unfortunately, the rod is in that space so I need to come up with something else.

 

[rtj]

BBshark, there was a guy building a snorkel that went over the rad to an airbox filter on cf. That design might allow you to put a filter on the inlet and tie into your TB. I was kind of amazed he snaked it through there. Probably not hard to tweak/fab.

https://www.ebay.com/i/233644271483...MInoKJ1MSP7AIVUMDICh3gwwchEAQYASABEgKdQfD_BwE


On another note, cf one piece roof. Lightweight isn’t cheap. I posted some of his vids and he mentioned this, but didn’t show it.

https://www.dynamiccorvettes.com/product/one-piece-roof-carbon-fiber/


Fiberglass lower cost version

https://www.dynamiccorvettes.com/product/one-piece-roof-fiberglass/

 

[69427]

Pondering aluminum glasspack mufflers.

The in-progress picture above is one of the aluminum mufflers I made a few years back, replacing the Dynomax turbos previously on the car. The Dynomax pieces sounded nice and flowed well, but were 16# each. The aluminum replacements ended up at 10# each. They flow well and I'm told they're pretty quiet at WOT. They were a lot of work to fabricate, but I think I can make a couple glasspack syle mufflers pretty easily. They ought to be noticeably lighter, and if the noise level increase is also noticeable, I can just use them at the track, and keep the full size mufflers for street duty.

 

[BBShark]

BBshark, there was a guy building a snorkel that went over the rad to an airbox filter on cf. That design might allow you to put a filter on the inlet and tie into your TB. I was kind of amazed he snaked it through there. Probably not hard to tweak/fab.

Haven't made this yet but according to my measurements, this will work.

 

[rtj]

How do you plan to fab it? That guy at cf was making two halves and then bonding them.

 

[COLE SWEAT]

Has anyone tried pulling the air from the cowl or windshield wiper space

 

[69427]

Finished up the front bumper aluminum center support bracket a while back, and got it installed. The original steel bracket was 6.8#, and the replacement ended up at 4.4#. I was satisfied with that reduction, given that I don't feel like I scrimped on the material thickness that I used.

Leverage wise, a bit more than that 2.4# off the front axle, and a wee bit more of the vehicle rear mass allowed to settle back down on the rear axle.

Win-win.

 

[phantomjock]

Excellent! That means you now have 2.4# for a small carbon fiber splitter - or low weight PVC airdam. Get back that "missing" mechanical downforce (weight) back at speed with some small aero improvements!
(put tongue in cheek Emoji here...)

Cheers - Jim

 

[69427]

Excellent! That means you now have 2.4# for a small carbon fiber splitter - or low weight PVC airdam. Get back that "missing" mechanical downforce (weight) back at speed with some small aero improvements!
(put tongue in cheek Emoji here...)

Cheers - Jim

My Pace Car spoiler has a short "splitter" length in its design, and I've got a sheet of 1/8" Lexan under there going back to the suspension crossmember. The Lexan sheet and brackets weigh 4.6#, so the bumper bracket weight reduction helps get rid of about half of the mass penalty of the "splitter pan".

 

[69427]

While perusing one of the local U-Pull-it junkyards I noticed a couple cars with the bumper covers removed, and I noticed what looks like an extruded aluminum structure underneath. The shape looked like a capital B (looking into the extrusion). Got me thinking if one of these items might be a decent candidate to replace the extreme rear (bumper) crossmember on my frame. Down side is I suspect the stock steel crossmember weighs next to nothing, but it's just a guess.

I think I'll do some measurements of the frame crossmember material thickness and width/length, and try to calculate the volume/weight of the crossmember to see if this idea/change makes any sense.

 

[rtj]

Ecklers is selling a 17 lb acrylic single piece roof for C3’s pretty reasonably.

What is one t top? 15?

 

[69427]

Ecklers is selling a 17 lb acrylic single piece roof for C3’s pretty reasonably.

What is one t top? 15?

I suspect you're pretty close. I've got mine stripped for more helmet room, and IIRC they're now 12# (each). The one piece unit you're talking about would shave another 8# up high.

I'll take a look at that. Thanks.

 

[69427]

Ecklers is selling a 17 lb acrylic single piece roof for C3’s pretty reasonably.

What is one t top? 15?

I took a look at that top a while back. While I would love to take some additional weight off the car (particularly up high), the price tag for this top is out of my budget ($/#).

I appreciate the suggestion though.

 

[69427]

Later C3 battery cable question.

I read on another site where a poster says his '75 came with an aluminum positive battery cable. Anyone know if this is correct? This is the first time I've heard that mentioned.

 

[redvetracr]

why not buy a set of fiberglass replica bumpers? they are only $2000 a set

 

[69427]

why not buy a set of fiberglass replica bumpers? they are only $2000 a set

I have to admit you've managed to provide both a question and the answer in your post. :amused:

 

[mfain]

why not buy a set of fiberglass replica bumpers? they are only $2000 a set

I have to admit you've managed to provide both a question and the answer in your post. :amused:

Pull molds off your bumpers and build a set out of fiberglass or CF - a little time consuming, but not that expensive. I am finishing up a CF hood and removable top - should shave about 50# total.

 

[rtj]

https://customimagecorvettes.com/product-category/c3-corvette/fiberglass/custom-image-fiberglass/

Front and rear bumper kits $650 ($450+$250).

 

[mfain]

https://customimagecorvettes.com/product-category/c3-corvette/fiberglass/custom-image-fiberglass/

Front and rear bumper kits $650 ($450+$250).

By the time you built molds and then the finished part, you could not do them any cheaper than that! There website description of the front bumper also has some interesting info about finishes.

rtj - new math? LOL

 

[rtj]

https://customimagecorvettes.com/product-category/c3-corvette/fiberglass/custom-image-fiberglass/

Front and rear bumper kits $650 ($450+$250).

By the time you built molds and then the finished part, you could not do them any cheaper than that! There website description of the front bumper also has some interesting info about finishes.

rtj - new math? LOL

No fat fingers on the iPhone. It was supposed to be $200 not $250. I added the (faulty) math later.

Yeah, agreed molds take material and time. Not to mention fumes inhaled vs $650.