This thing is way too cool and you’re making some great progress! Any thoughts on deleting the cowl vent?
Bonneville Landspeed Racing - Let's Try a Thing.
- Thread starter 71GSSDemon
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Thanks! The cowl vent grill is just open to the engine compartment at this time. My current plan was to cover it from the outside in case I want to finish boxing it in underneath and having fresh air available inside the car. Maybe with manually opened doors or flaps.
TT5.9mag
Two atmospheres are better than one
Block it off. The 2-3 mph you’ll pick up is worth it. Race cars don’t have fresh air vents.
Use a Parker pumper and push fresh air in to your helmet.
Sorry for the confusion. What i meant was for any street driving, it could be made to work.
I also wonder about removing the door handles and adding ones like drag cars now that the vent windows are gone. Top of door at the vent windows area I wonder what a 4-5" hole in the window would do aero wise in that area??? Could it still net a gain over the stock door handles?
My buddy has an ice or water tank that pumps cool air to his helmet. Seems like something I want
TT5.9mag
Two atmospheres are better than one
Interesting thought about the door handles. An open hole has to present some kind of drag, the question is more or less than a door handle on the outside of the bodywork. I’m sure someone in that world has tested both in a wind tunnel.
TT5.9mag
Two atmospheres are better than one
Our truck has a pumper for each person and it’s amazing how much it cools you off just to have fresh air pumped in. Lots of drag week guys are wearing the shirts that you can circulate water through. Seems those are super popular now. I know it’s brutally hot in bonneville and wearing a five layer fire suit sitting the car with your helmet on can be miserable. Something to cool the driver off is a good idea.
TT5.9mag
Two atmospheres are better than one
To me to seems like it is a net positive as most all very fast drag cars have them and no external handles. But then, most have fiberglass or carbon doors that aren't factory in any way. I have search all over the Google and can't find a definitive answer. I will likely do it.
I am cutting the drip rails and flush mounting the side windows to help
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TT5.9mag
Two atmospheres are better than one
I like it. And the hole can be small enough for a one finger door pull if you use the small lightweight drag handles.
I will have to see what I can do with the heavy stock doors
That looks awesome.
Too bad you didn't design for Dodge back then lol
Well, I didn't get to work on the car like I wanted to, so only a couple little things done. Every little bit gets me closer though. I have been able to order a lot of little things (header studs, gaskets, switch panel, plumbing coupler, etc). I do have a week off over New Years, so hopefully it wont be too cold and I can work on things.
So, I have a dilemma. I am trying to sort out what gear ratio to start with. If looking to be at max effort at 2.25-3 miles. Also, it seems a taller gear ratio seems more common that overdrive trans. It should be accelerating faster with a shorter gears and OD, but traction is also a major factor. The car currently has 2.94 gears. I know of a 2.76 center I could likely get. I even have a 2.50 quick change that could go in, but where to start? To me, the 2.50 QC is better for when I make the long course. Thoughts?
TT5.9mag
Two atmospheres are better than one
It’s rpm, tire diameter, final drive in trans, and final drive gear. It’s just maths.
My guess is you’ll want the 2.50 gear with a big block. But don’t overlook driveshaft critical speed. A 3” steel tube driveshaft probably isn’t going to cut it.
My guess is you’ll want the 2.50 gear with a big block. But don’t overlook driveshaft critical speed. A 3” steel tube driveshaft probably isn’t going to cut it.
Thanks Mike. I understand the maths, just don't want to reach 6000rpm at mile 1 for some reason, and carry that for another 2 miles (yes exaggerating). It would be best to reach 6000rpm at the 1/4 and carry it out the back door, yes? I know when Aaron first brought his roadster there, he was running (IIRC) 9200rpm from mile 4 to 5. A gear change and slight aero, he picked up 21mph! I just don't know how to guess the given distance and rpm. It will be CoD and HP related, but just trying to sort out the best practice.It’s rpm, tire diameter, final drive in trans, and final drive gear. It’s just maths.
My guess is you’ll want the 2.50 gear with a big block. But don’t overlook driveshaft critical speed. A 3” steel tube driveshaft probably isn’t going to cut it.
I plan to run a 4 or 5" aluminum driveshaft for CS, but when going to max effort run, will likely change it to a 2 piece race shaft as it is 57" length.
What are your thoughts on a 2.50 ratio vs a 3.23 and OD? Calculators say 2.50 with 1:1 and 28" tire is 200mph at 6000 or 3.23 with 0.76OD and 28" tire to be 203mph at the same 6000rpm. The 3.23 combo would accelerate quicker but traction will be an issue.
If Viren ends up full on board, then 2.50 AND the OD with a 2 piece shaft.....
TT5.9mag
Two atmospheres are better than one
I think I’d rather have the 2.50 gear and a 3 speed than a 3.23 and an OD 4 speed. You likely won’t hook up for the first mile with the second combo so it won’t accelerate faster.
That's hilarious.... Once I register for a race, then I can change it.
Would you be able to make it to WOS this coming Sept? If I can get it done????
TT5.9mag
Two atmospheres are better than one
That would be amazing! I am getting pressured pretty heavily, so I am trying. I have vacation set aside for WOS Sept 2-10.
TT5.9mag
Two atmospheres are better than one
10-4 I’ll do the same and start making plans.
What size shirt/coat do you wear?
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