Roadracer's #997 build

[RoadRacer]

Installed brake pressure gauges in the dash so I can log data as I change f/r bias. My version of datalogging ��
The pressures I measured at the calipers in January (see here) were 750psi/1500psi - these still show the same.

https://youtube.com/shorts/dunQsxBcS...NUXiA3e9UeQ0Qx

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[RoadRacer]

Did another autocross yesterday, I missed one while on vacation so it's been a while.

It rained heavily in first session, dried in second and I was luckily running in third session. So it's hard to judge improvements against others who may have been running in worse sessions. But I did get 24th fastest (and the R class was running third session too). Car felt good!

[RoadRacer]

Following on from this post about 3-link panhard bar mounts, I braced mine - for no other reason than it's a quick fix

panhard-fix.png

[RoadRacer]

Following on from my thread "Has anyone built headers for side pipes on hot rod?" - the headers are an easy fit (with one caveat)!

They bolted up just fine to my SBC, with loads of space around the chassis. This opens up space for potential easier steering routes too.

And remember, these headers (Schoenfeld part #1346) are just $469.95

Take a look:

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Now here's the caveat.. it touches the 'glass body here. Tight.

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So I'll talk to them about attaching the collector at a slightly different angle - they may want to send me another set to test. We'll see. Otherwise I'll modify these myself. Now onto the side pipe/muffler investigation.

BTW, I did measure dB at 50ft to the side just to compare. The current FFR w/borla muffler was at ~89db at ~6000.

The new open headers were ~108db. They sound great! But would get me kicked out of any autocross I tried to go to.

[progmgr1]

Considering that 6 dB is a doubling of loudness, I can see the issue. However, this will look wicked cool when its done.

I always appreciate builders who "color outside the lines" to make their cars unique.

Keith HR #894

[RoadRacer]

Considering that 6 dB is a doubling of loudness, I can see the issue. However, this will look wicked cool when its done.

I always appreciate builders who "color outside the lines" to make their cars unique.

Keith HR #894

Yeah it’s fun. This was driven by two things.. 1. The gen1 floor touches the exhaust throughout so is a rattly mess. 2. I wanted bigger primaries for my motor. Now 1.75 up from 1.5.

[GoDadGo]

Great News!

[RoadRacer]

I never mentioned it here, but I went to a hub dyno at the weekend. They only gave me wheel speed, not rpm, but luckily you can calculate it given 4th gear (1:1) and rear ratio (3.73). From there I could calculate torque using t = hp / (rpm/5252)

So here's the result, I've adjusted this by 115% to account (somewhat) for wheel hp vs motor hp, but of course that's a complete guess.

peak hp 5500-6000, peak torque 4200-4800 - both pretty flat at their peak.

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[RoadRacer]

Having discussed with Schoenfeld, we decided to send mine back, and they'll send a new set out (I did move to 3" from 3.5" though, after noticing 3.5" is far less supported for mufflers).

This new set will be sent fully welded up, except for the collector which will be loose in the box. That will allow me to adjust the angle and space from the bodywork.

[Just 1 More]

Having discussed with Schoenfeld, we decided to send mine back, and they'll send a new set out (I did move to 3" from 3.5" though, after noticing 3.5" is far less supported for mufflers).

This new set will be sent fully welded up, except for the collector which will be loose in the box. That will allow me to adjust the angle and space from the bodywork.

https://youtu.be/Z0YIJQ1jgEI

[RoadRacer]

Haha well the exhaust is on. It’s been a journey and I’m not quite there yet. A friend and I spent all day yesterday getting it on and it’s not bolt on.. but it could/will be. Schoenfeld need to make a little tweak to give more body clearance and I’ll talk to them about that.

We spent most of the time heating and bending the headers with oxy-acetylene torch - had to put a lot of heat into them to bend them out. Heated along the top curve of the header. The angled bend I bought from collector to muffler was wrong angle too - hard to estimate off the car. So more heat and bending. But that’s going to be replaced with a proper and removable piece soon.

Ultimately we had to get it all on, hung and tacked together so I could drive home. Our first step in morning was to cut the old stuff off

Most parts leak (not fully welded), the old header gaskets got damaged (will put my new set on, but I saved them until final fit) and currently it’s rigidly welded to the car. No rubber mounts. So this is very much in proof-of-concept mode.

Worse, for most people anyway, is that the body curve is pretty significant. I decided to lose the bottom of the door completely, and cut the corner. Better to have close to body (much less chance of burns). I have so far found that the way I get in and out does still work.


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[Just 1 More]

Looking good James

[RoadRacer]

My latest autocross.. pretty tricky and car felt loose even though I was trying to tune it between runs. So I was too timid this time.



Everyone loved how the car sounded though, I had all the seams welded during the week. It was right at the sound limit though.. the sound check guys were alternating between "just under" and "just over" the limit. I still got all 6 runs, but I'm going to rotate the end pipe to point down rather than sideways which usually helps.

The 200 mile drive though.. this is the first time in thousands of miles that I felt beaten by the sound. It's too loud honestly. But sounds amazing LOL. This morning I drove to home depot and got some 26db corded ear plugs and it makes a huge difference. At least for longer drives.

[GoDadGo]

Thanks For Taking Us For A Ride!
.....Also, I Love The Headers!

[RoadRacer]

Exciting! Since I want to do a lot more circuit running in 2025 I just ordered some big brakes from Gordon Levy

Basically this setup: https://a.co/d/3uSAT1t

Aero6 14” and superlite 4 13”

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[Just 1 More]

Exciting! Since I want to do a lot more circuit running in 2025 I just ordered some big brakes from Gordon Levy

Basically this setup: https://a.co/d/3uSAT1t

Aero6 14” and superlite 4 13”

IMG_2646.jpeg

We talked about brakes a while back and you seemed pretty happy with the factory brakes with the upgraded pads...... I'm Looking forward to hearing the amount of improvement.

[RoadRacer]

We talked about brakes a while back and you seemed pretty happy with the factory brakes with the upgraded pads...... I'm Looking forward to hearing the amount of improvement.

Yeah I am happy with stock for road and autocross.. but will run out of brakes at the track. A lot more sustained heat.

[RoadRacer]

Just realized that I hadnt posted my latest video from our club's "track sprint" - basically a 2/3 lap of a lap private track called Harris Hill.

I hadn't done any laps here since this event a year ago, so I really need to get more practice and get quicker at this track. Unlike autocross, this track doesn't change!

In 2025, this is one of my focuses: knocking 6-7s a lap off this (quite timid) lap. Part of that is the reason to upgrade the brakes above. 6-7s sounds like a LOT (and it is) but others in corvettes are hitting 8-9s quicker than me, and that must be stopped

[RoadRacer]

My last official autocross of the year, although I hope to get some more track time to get a base time for my push at much-improved track time in 2025.

I was very happy with this run. I had 5 clean runs, and each one improved on the last by at least 1s.