A bit of tweaking to fix some numbers plus a couple additions:

wheels -24.4 lbs (BC Forged RT50 vs OEM 7-spoke)
tires -4.0 lbs (MPSS 245/285 vs OEM Bridgestone 235/275)
brake rotors -18.0 lbs (Wilwood 2-piece vs OEM Brembo)
battery -29.5 lbs (Redpants Braille kit vs OEM Varta)
muffler -27.0 lbs (estimate, RSC vs OEM)
high-flow cats -8 lbs (RSC vs OEM)
headers -8.25 lbs (VelocityAP vs OEM)
EGR delete -1 lb (VelocityAP delete)
cargo divider -10 lbs (estimate, only when at the track)
front fender liner pads -1 lb (removed)
oil catch can +2 lbs (VelocityAP/Redpants addition)

TOTAL: 129 lbs weight loss

Still to do:
Recaro Profi SPG seats with Redpants mounting hardware -50 lbs (estimate, both seats combined)
VelocityAP clutch and lightweight flywheel -17 lbs (way down the road)
Aston Martin Racing lightweight front/rear bumper beams -50 lbs (estimate, if I can get them)

 

Was the dent in the nbr 3 DS pipe bend done intentially or ???

 

Yeah, the dents you see in the OEM headers are there to allow easier access for tools. One of the ways aftermarket headers help with flow is by eliminating those dents.

 

Telum, you are doing a great job turning your 4.3 coupe into an outstanding performer. I review your weight reduction list for guidance.

Based on my experience, however, I have one suggestion for your 'to do' list...move up the 'Velocity AP clutch & lightweight flywheel' from "way down the road" to "as soon as possible".

The change in the vehicle is much more than a 17# save. Our Montreal Connection, Irish, labeled it "smooth". Well it is smooth, a 17# save, and much, much more. It is like purchasing a new, much refined car, that you will be so enthusiastic about you can find yourself offering it to friends to sample. Like me, I do it with my coupe. (Not to everyone, just a couple that are "qualified".)

 

Thanks! It's hard to describe just how different the car feels than a standard 4.3L V8V. It's so much sharper, quicker, more responsive, but not in an unpleasant way at all. It's just trimming the fat off the car and reaping the benefits.


I'm really looking forward to the clutch and flywheel, but it isn't financially feasible right now. In addition to everything else sucking me dry, I just found out that I have a bad head gasket on my 4Runner (my daily driver) and that's a few thousand bucks to fix. Discovered the issue while draining my oil catch can on that vehicle - another reason to use catch cans!


My clutch is still going strong but I'll be swapping to the VAP setup when it gets replaced. Can't afford to spare the extra cash on it until it's necessary

 

Somewhat relevant

 

Some initial impressions:

The exhaust note is much smoother at lower RPM. It is in higher RPMs as well, but not very noticeable there because the exhaust pulses are fast enough that it's harder to tell. The OEM headers had a rougher sound at low RPM. The upside to that (which is entirely subjective) is that the exhaust sounded mean. The smoothness has transitioned it towards more refined and less angry.

Yet to be answered:

Actual power difference between OEM and VAP headers. It'll take a dyno to sort that out, but with some caveats: I'll need to benchmark against another 4.3L with all the same modifications as mine, minus the headers. Since that's very unlikely, I'll trust Stuart's own testing on their power gains. I am, however, planning to test my car against a completely unmodified 4.3L in the not-too-distant future. I'll be looking at total weight, weight distribution, horsepower, torque, and power curves.

Regardless, my car is very, very different than a standard 4.3L. Much faster, much more agile, much more responsive. All the changes in total make a HUGE difference.

Wow, that's an awesome video. I love tests like that! I'm honestly really, really surprised by those results, but it makes me question how headers with dyno-proven results make their power when denting them so badly has no effect. You'd think it'd be power gained, power lost.

One thing they don't address in that video, though, is engine response. While the power may be consistent at a specific rate of throttle input, what about at a changing rate of throttle, like you'd see in actual driving conditions?

 

There is no power loss form OEM exhaust manifold dents.
Simply because the OEM exhaust manifold as a double wall to reduce engine bay temp and the dents are on the exterior wall...
Just measure the outside diameter and the inside diameter of the pipe and you will understand

 

I had some pretty devastating news over the weekend so I'm bumping this thread with some updates to refocus and help get my mind back on track.

I got the insurance payout for this little incident: https://www.6speedonline.com/forums/...ts-itself.html

My options were to 1) let the repair shop handle it, 2) do everything but the paint myself and pocket a huge chunk of money, or 3) buy race car parts. Obviously the easiest option is the first one. It's the least amount of stress and effort and it comes with a full warranty on the work. But option two would give me a ton of money to use responsibly for other things. Option three is completely irresponsible.

So here are the race car parts I'm getting!

GT12 carbon fiber hood
GT4 carbon fiber side sills
GT4 front bumper beam and associated parts (so long as they confirm that there's a decent weight loss to justify the cost)
Carbon fiber front lip (working with Stuart to decide between a couple options)

Vince_1972 has been extraordinarily generous and is sending me his old 8-bar grille all the way from France. I'll be popping every-other slat out of it to turn it into a 4-bar grille to give it a more sporty look. It's been coated black so it'll blend with all the carbon fiber.

I have some carbon fiber vinyl wrap that I'll be using to cover the side strakes. I might get actual carbon fiber ones down the road but since I have this stuff handy it's an easy, cost-free change.

I'll probably end up getting black exhaust tips, carbon fiber trunk lid spoiler, and carbon fiber rear diffuser as well, but that'll be after I recover from buying all the above... since all of it is pretty much draining my cash. The hood alone is absurd. The only reason I even considered it was because my out of pocket expenses for all of this are greatly reduced by doing the labor myself, getting parts at my vendor discount, and Vince's generosity.

Parts are being gathered as we speak and should be shipping out this week, arriving here next week. Paint is scheduled for the 29th, and I have a photoshoot scheduled for September 3rd. I accidentally started dating the model that will be in the pics so Mike and Greg will actually get pics this time

 

Well very happy that everything is working out for you... Looking forward to the pictures...

 

Just heard back: The GT4 front bumper beam drops 7.4 kg (16.25 lbs) from the nose of the car (ideal location, but I was hoping for 25-30 lbs). I'd get it, but the cost of everything associated with it makes it out of my budget with everything else I'm doing. The bumper requires brackets for the headlights, a new tow hook, mesh that replaces the grille... all of which basically doubles the price. Definitely still on my list, but I'd rather put the money towards suspension and a clutch/lightweight flywheel.


Thanks, hoping this comes together cleanly

 

Whatever weight saving you gained in this thread, back to square one

 

Going to get the parts yourself and let the shop reimburse you?
Wish I had thought of that!

 

Got paid directly from the insurance company
The downside of course is that I've shifted all liability for repairs onto myself.

 

happy to hear you've turned this thing into an oppty for additional mods. when it comes time to take apart that 8bar slat, would very much appreciate some info on how to go about doing it and what not.

thanks!