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Andrew,
Thank you and I share your concern.
No, I haven't run this tank in competition, but it is made for sprint car use. I have made my own dry sump tanks before and have put a swirl pot in the top of a rectangular tank with the discharge still having to cascade over several perforated horizontal levels. Since this one is made with a removable lid, I may lower the cascades and add at least a 180 to 270 degree swirl surface. I was already planning to add more levels because it only comes with two. I'm also going to increase the vent capacity from a -6 to a -10.

Ron

Long ago in a discussion about oil aeration, someone suggested pipetting out a few cc of oil from the tank and using a reloading or other precision scale to weight it and compare it to the same volume settled oil. The difference in weight would indicate the amount of air entrainment.

I never got around to trying it, but I *have* seen engine oil so aerated it was foamy... that can't be good for bearings.

Thanks for the suggestion TRX. I may take a sample of "processed" oil before and after I make the changes to the dry sump tank.

More evolution has begun. The live rear axle has been removed and is being replaced by a Mazda IRS. RX7 FC uprights, half-shafts and stub axles, a Miata diff housing and a GSL/SE limited slip diff are being used. The frame structure to hang the housing is mostly done. The uprights have been mounted on jigs with the axles installed. Now the A-arms need to be made to connect the uprights to the frame.

What lead to the swap?

Rough pavement handling?

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-Andrew
Build Log
Youtube

Andrew,
Yes, one of the considerations is the surface that we run on which has lots of "character" and a few places with some bumps that upset the car. I also have 4 wheels with 2" more backspace than those that were on the car. The IRS setup is fortuitously 4" wider than the live axle. This allows me to have another set of tires with a different compound. The swap also reduces the unsprung weight by 40 lbs with a small net reduction in total weight. The IRS also provides the ability to adjust the camber to what best suits the tire.
Ron

I'll be real curious to see if your track times improve significantly. There is that constant debate about how much better an IRS is, and if it's worth doing, etc.

With my own build, it's one of the things I wonder about. Will my live axle be the tail that wags the dog, or will it be OK? I went for the simplicity of a single donor build, so it was a compromise I elected to make rather than add in a Lincoln or Explorer IRS at rear.

I won't have any way of knowing what that decision will "cost" me, however.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Lonnie, your car will be "OK" with the current setup. However, it may tend to jump sideways if you are pushing it through a corner that has bumps in it. In my '65 Mustangs, the rear suspensions were both converted to IRS. My daily route had me making a left turn through a bumpy intersection and the stock rearend always jumped over a couple inches in the bumps. The IRS conversions made that turn without any drama. On the street, it's just a comfort consideration. In competition, there is lost time in having to countersteer for a loose rearend. Just my $0.02.

Transitioning a 65 Cobra kit from solid axle to IRS made me a believer. The car was a dream to drive by comparison with the IRS and really hugged the road so much better especially on rough roads or even just over fairly mild bumps.

Same tires, same everything.

Making U-ies under overpasses, even on concrete roads the solid axle was an exercise in restraint. Even in 3rd gear the more you put the throttle down the more the back end came around, but with the IRS you could make the same turn in 2nd with more throttle and the car was still planted. In that situation the extra adjustability is what we put it down to.

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mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

Any pics of the structure to mount the nose would be much appreciated. That is one of the points that feeds some punishing loads into the chassis. Thanks.

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My build http://www.locostusa.com/forums/viewtopic.php?f=35&t=7370

jaf,
The pic shows the cross bar that the nose will rest on. The cross bar is 2 x 3 x 0.120 wall. The nose will be pulled down onto the cross bar by a Ford 9" leaf spring u-bolt fitted transversely over the nose. Very simple and worked fine on the EMod car for decades. I'll update with pics of the assembly after it's completed.

Ron

The U-bolt arrived today. So, through holes were drilled in the crossbar and the internal bushings were fitted. The crossbar and the nose resting plate were welded in.

Simple, light solution.

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My Haynes/Miata build: http://locostusa.com/forums/viewtopic.php?f=35&t=3774

Hi Ron,

as you may know, i am rebuilding my duratec, this is the most difficult motor i have had to build in my life, it is clearly not meant to be done and i have built some complex engines in my time.

however, like you i do have access to a lot of stuff,.

the keyway in the crank, did you have that cut at TDC and what size key did you use? i had mine cut at BDC because the aluminum pulley i am using has three webs, one with a hole for the timing bolt so i felt it was better to have the keyway cut where a web was, i used the cosworth sprocket which has a 5mm key so that dictated the size of the keyway in the pulley and added a steel seal saver to the back of the pulley the cost of the keyway was $300 for the crank and pulley machining, i believe that the massive cranks have the keyway at 90 degrees from TDC.

have you done anything about the cam sprockets?, i used the mazda washers.

did you replace the main bearings and if so, did you use selective sizes?., i reused the mains and fitted king bearings to the rods

did you replace the front crank seal?

what pistons and rods did you use?

John

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this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

Hi John,
I used the forged crank from Massive for the 2.0 with a 1/8" keyway cut in the crank (at 90 degrees) and the chain drive sprocket. I used the stock harmonic balancer and cut the keyway myself with a broach from MSC.
For the cam sprockets, I used ARP bolts and, like you, added the Mazda friction washers.
I used the main bearings that Massive sells with the crank which are King Racing XP series. The rod bearings came from Clevite. The rods were made by K1 and the pistons are the 11.2 to 1 sets for the 2.0 from Supertech.
I did not replace the front seal. Thanks for sharing the info you obtained in replacing your front seal.

Ron

The wishbones and pickup points have been assembled and tacked together/tacked inplace.