I like that chart. Funny, if there is a chart showing examples of nose down engine setups there must be applications where this is considered acceptable.
Well, it seems nose-down cars abound.
> Drag race cars have a 2 to 3 degree negative engine angle, the
> engine will tip down in front.
www.hotrodheaven.com/tech/chassis/rideheight.htmHere's a 63 Chrysler, even:
from
cacklefest.com/Chizler-V.shtmlAnd I found this a good thread/post:
> Generally speaking while it would be nice to always have the
> "choice" of how to hang the engine (in reference to crank "nose
> up", crank level, or crank 'nose down" angles) in every type of
> drag car, usually (unfortunately) the body/chassis/front
> suspension type & rear slick diameter most times will dictate how
> the engine angle will have to sit in order to clear
> steering/suspension and also line up with the rear pinion.
www.460ford.com/forum/showthread.php?t=121376&highlight=pinion+angle&page=2And
> The examples show how the engine might sit when factoring in
> different types of "intended use" (street vs strip only), or the
> different crank nose heights of different chassis (because of
> different front suspension types), or the different diameters of
> slicks (which controls how high off the ground the pinion will be).
Clearly, "nose down" was done 49 years ago, and people at least think about the choice to have "nose down" today.
Here are the Arthur "steps to vibration free, efficient power transfer, long life u-joints":
Step 1) the transmission tail shaft and pinion shaft must be parallel (in three dimensions)
Step 1a) parallel in side view:
www.1800philes.com/t5.htmlStep 1b) parallel in overhead view:
jniolon.clubfte.com/drivelinephasing/drivelinephasing.htmlA is bad. B is good.
Note that that parallel may or may not mean "on the exact same line". See step 3 for "parallel not in a line" vs. "parallel and on the same line".
Step 2) For drag racing, we want them parallel upon power transfer (not at rest). At power transfer,
> the pinion changes as the differential goes through its vertical
> travel and that it rotates up when torque arrives. The amount of
> upward rotation is limited by the suspension linkages. These
> include the leaf spring, which has a lot of pinion rotation, the
> commercially available ladder bar, which has less pinion rotation
> than the leaf spring, but more than an equal-length four-link
> system.
www.stangtv.com/tech-stories/chassis-safety/drivetrain-angles-increase-torque-and-improving-hook/So after statically getting the trans output shaft and pinion parallel, the pinion is angled down a bit (depending on leaf spring/ladder bar/4-link) so that upon power transfer, it angles up, and the pinion is parallel with the tailshaft of the transmission.
Step 3) Transmission shaft and pinion shaft. Must be parallel, but what about being in a line?
Step 3a) we want them in a line for drag racing at power transfer (efficient power transfer, and don't care about u-joint life).
www.460ford.com/forum/showpost.php?p=693027&postcount=13Step 3b) and we don't want them in a line for street life (want long u-joint life)
Although it's low strain:
www.justanswer.com/gm/4s1xy-gmc-sierra-2500-hd-check-pinion-aangle.htmlbeing that there are no angle changes by the u-joints, the cups don't get any action and the grease doesn't lube the needle bearings and the u-joints wear out:
www.agcoauto.com/content/news/p2_articleid/189Step 4)
> yokes should be positioned so that their center lines are on the
> same axis. The action of the opposite yokes tends to cancel out
> the speed variations of each other.
jniolon.clubfte.com/drivelinephasing/drivelinephasing.htmlStep 4 is known by anybody that makes driveshafts (at least useful driveshafts).
> don't let these other guys get you down, you are doing
> something completely "one off" never been done before. You are
> the engineer on the project, you just need the best work out of
> your subcontractors to get the job done.
Right on!
I think I'm comfortable with assessing that there are no difficulties (as far as motor life / power is concerned) with running at -2 degrees. So I still need to ensure that the trans can handle it, and that the rear end can handle it. Here's all the stock data:
> Are you having a custom fuel tank fabbed or are you using a
> stock tank?
Mainly stock, is the plan. I want it to look like this:
There's not much to see there, so it seems I have some wiggle room in what to do, but it would also seem straightforward to re-use the stock tank (with modifications), so that's my plan.
From BBC:
www.bluesbrotherscentral.com/forum/topic/8327-theres-a-new-marin-county-sheriff-in-town/page__view__findpost__p__117370pic 1 is a page from the April 2011 issue of Hot Rod showing an aftermarket in-tank fuel pump.
It looks like quite a nice setup. The pump itself
Aeromotive|11101 - A1000 Fuel Pump
aeromotiveinc.com/products-page/fuel-pumps/11101-a1000-fuel-pump/can be mounted inside the fuel tank
Aeromotive|18668 - Universal A1000 Stealth Pump Assembly
aeromotiveinc.com/products-page/stealth-fuel-systems/18668-universal-a1000-stealth-pump-assembly/which is a feature I like (quiet operation, and being surrounded by fuel keeps it cool). In the standard configuration it must be mounted vertically and needs a minimum of 9.75" of vertical distance to the bottom of the tank
aeromotiveinc.com/wp-content/uploads/2011/02/18668_18669.pdfThe article talks about an XRP low-profile 90 degree fitting. I believe they're talking about the info in pic 2
from
www.xrp.com/XRPCatalog.pdfI don't want to cut the trunk floor for clearance for fittings - I want the trunk open and clear so it remains the most impressive display of the awesomeness of a giant 1970s trunk.
I don't have a fuel tank in the house, so I don't know if the tank is at least 9.75" deep (plus distance for the fittings). If it's not, then an option is to use their weld-in sump kit to mount the fuel pump horizontally. Its actually quite groovy with baffles and integrated fuel filter. It might be a nice option anyway because I wouldn't need to drop the tank to do any work on the pump or fittings.
Aeromotive|18651 - A1000 Stealth Sump Kit
aeromotiveinc.com/products-page/stealth-fuel-systems/18651-a1000-stealth-sump-kit/The standard fuel setup then requires a 10 micron filter after the pump, and a pressure regulator before the return line back to the tank.
your friend in not interfering with a comfortable trunk,
arthur