I've tried to read this whole thread. I try and read a little at a time or my brain hurts. :)

I have a question regarding gas and weight savings. I apologize if it's already been covered.
During the competition, are you allowed to use a different size gas tank? I did a quick google search and see that a gallon of gasoline weighs aproximately 6lbs. If Im not mistaken, durring the last competition, you used less that 3 gallons of gas. 3 gallons should weigh about 18lbs vs 10gallons at +60lbs.

Are you allowed to lengthen your inlet manifold runners or use a custom equal length design?

Quote:Excellent question/comment. There are no rules regarding the level of modification at our events. It's pretty much anything goes. One of the only rules we have is that you cannot have an assistant ride ahead of you for drafting purposes. Most participants are not as motivated as I am though, so there haven't been any fuel cells used in competition. That is probably because most people are driving fuel injected cars. It's a great idea though, and one I may act on in the future. Last year I used 1.91 gallons for 118.7 miles so a 2 gallon tank would do it. That would save me from carrying 8 extra gallons = 48 lbs!

Thanks for sharing your good idea.

Mike

Quote:Absolutely. This sounds like a mod that should help gain the low end power a fuel mileage car is seeking. Has anyone tried this before?

Sure, lots of people here running equal-length intake manifolds, they help high end more than low end. I recommend: Round port head, early A12A camshaft, DCOE manifold with length extensions, 40mm carbs with 32mm chokes.

I took a look at my front brakes this afternoon. I raised the car up, made a chalk mark on the tires, and gave the wheels a "spin test" [by hand] and counted three revolutions each side. So I decided to take them apart and clean them. I lubed the slides and found an NOS hardware kit in my basement. I took advantage of the kit's extra parts to add a second spring between the pads to help them release more completely. Normally there is only a single spring on only one of the pins. The spin test yeilded 6 2/3rds revolutions afterwards. Must have helped.

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Every bit helps! Cant believe it made such a huge differnce. Nice going

The longer the manifolds the better the low end torque
equal length helps with pulses so necessary at all rpm levels
not just high rpm. Also high rpm requires shorter runners.
Ive had quad 34mm mikunis with 20cm runners and compared to
the 10cm runners made a hell of a difference down low.
Problem was with clearance on the suspension so had to curve
the runners up which was fine as the manifold was made from
mild steel. The other mod was sand blasting the innards and
outers to help with fuel atomization and the outer to help
stop frosting. It would have helped better if I ran a boxed
up section for water

I mounted the "economy" wheel/tire package [155/80R13's @ 50 psi] today. Next, I installed my home made chin spoiler [cut from a scrap Ford Contour front bumper cover] and blended in the edges with tape. Afterwards I put it up on blocks [yes I know cement blocks aren't safe - don't try this at home] to gain access to the entire undercarriage for belley pan fitting. I then began to fabricate the forward belly pan section.



This is now fitted under the car. That's as far as I got tonight. To be continued.....

I ended up with a 107 primary main jet, as the 109 was too rich for summer temps. After that I still wanted it a tick leaner so I got out the shop manual to see if there was anything I had overlooked that I could tweak. There was indeed. On my California emissions model, there is a manually adjusted altitiude compensator lever under the air cleaner. I never knew this, but owners were supposed to get out and switch the lever for higher altitudes [over 4000 feet] to keep the mixture optimal if travelling in the mountains. It opens a small air bleed port on top of the carburetor. I did this and then road tested it with the wide band again. Wow, I got just the result I was looking for. Now I'm at 15 to 1 A/F, just where I wanted to be.