JJLudemann's Design Thread

[BURKY]

Congratulations!

Thank you for letting us follow the build.

[JJLudemann]

JJ - Pretty cool and very thoroughly documented!

I have to point out a few things that I think will give you problems.
- The drive chain is not going to be happy. Having ONE idler sprocket is bad enough, but the directional changes, chain torque, chain "whip", then throw in a 2nd idler...

Good information. In order to change it I'll have to go to a more conventional design where the rear sprocket is moved back and forth to take up slack. In my design I need custom-length axle halfshafts in order to do that, so it'll have to wait until the car is taken apart next time.

When I had a header modded for my RFR, I brought the rear chassis half to my guy and mentioned where the bulkhead would be, and how much room he had to make the bends.
You have the pipes protruding really far out, before they even start to bend down.
You really want as much room between the tubes and the bulkhead as possible.
The collector area looks very close to the oil filter - you definitely want to be able to service that w/o having to pull the header.

Good call on that one. When I showed those photos to my header fabricator, he had the same reaction and voluntarily built a completely new set of headers at no extra charge. Now there is firewall clearance and the oil filter can be removed without removing the headers.

I have found that simplification is the best way to go, and also factoring in things like if the ECU is mounted right next to the header (I have actually seen this!) it's probably going to not end well.
The location you have for the ECU will see it get nasty w/ chain lube/oil, etc.
I made a few little 90* alum brkts which were attached to the rearmost airbox screws, and a thin alum plate w/ the double sided velcro to the back of the ECU and a few "insurance zip ties".
The ECU brkt while cool (and right down the pike from me at Lockheed!) and swiss cheesed is a labor intensive and heavy addition to the completed car.

Good point. Little bits of aluminum and grease working their way into the ECU connectors wouldn't be good. I think a little debris shielding is in order.

Have you kept an eye on total weight? Do you intend to run the car in a class w/ a weight minimum?

I have indeed worried about the weight all the way through the build. But now I have two sets of scales, one of which says the car will be a bit heavy, and one of which says the car is way underweight. I'm inclined to believe the one that says it's underweight, as when I step on those scales they give me the expected reading. I haven't calibrated the other on, on my gantry crane.

But my plan is to import SCCA FB almost completely unchanged to Thailand. I figure if we just adopt the complete SCCA rulebook we can avoid lots of squabbling about rules. "Hey, it's out of my control; it's the US rulebook", you know?

Just a few things that stood out, my FBro.

Good Luck w/ the final build, GC

Thanks!

-Jim

[JJLudemann]

I finally got caught up in my blogging:

Laying up a Carbon-Fiber Honeycomb Front Impact Attenuator
Building the Undertray/Floor
Custom Molding the Seat

And I guess you guys already saw this one: GSX-R1000 First Engine Startup







-Jim

[JJLudemann]

Hi all,

I've been trying for days to find a source for springs for my F1000. Summit Racing has them but won't accept my credit card or Paypal. I can use Paypal for shipping to Thailand only on Ebay, but Summit Racing doesn't list the springs I need on Ebay. Another guy has 400 lb/in spring on Ebay, but I'm waiting for him to get back to me on shipping cost. Other places I just haven't been able to find what I need among the vast array of springs. The specs on the springs I have are:

Free length: 140.5 mm, 5.53" (116.7 mm min, 151.7 mm max adjustment range)
ID: 45.5 mm, 1.79" min can go to 2"
OD: 68.7 mm, 2.70"

I need springs in the 300-500 pound/inch range.

Does anyone know where to buy these, or an online spring store where I can search by dimensions?

Thanks,

-Jim

[Mike Devins]

http://shock-shop.com/Hyperco/Coil_Over_Springs.php

[JJLudemann]

Is the 95cm maximum width for the diffuser the inside dimension or the outside dimension? It only really makes sense as an inside dimension, but I thought I'd better make sure since the rear wing 95cm max is an outside dimension including the endplates.

Thanks,

-Jim

[Mike Devins]

Inside Dimension

[Mike Devins]

was looking at the JRO video and this came up!

https://www.youtube.com/watch?v=tqvzVhj-_Qs