SPF #2285 Born, But Still Coming To Life

[Mike]

Robert,
I have a similar engine setup with the same EFI system. My install used a swirl pot in the little box compartment just in front of the rear wheel, the opposite side of the battery box. It is the shape and size of a beer can, maybe a couple inches taller. It is fed with a low pressure, high volume pump and all the excess goes back to the tank. A Bosch 044 high pressure pump pulls off the bottom of the swirl pot and feeds the fuel injection. With this setup, I have never starved the motor and have run it as low as needing almost 18 gallons to fill it up. In theory, that left a gallon in each tank if they are truly 10 gallon tanks.
On the Eight Stack system, the feed comes in one side, raps around and then feeds the other side. We found on the larger cu. in. motor, I was running too lean on the second side. The solution, for mine at least, was to "T" on the feed side of the throttle bodies and feed both sides and "T" off the back and return back to the tank. According to the ECU and computer, my lean condition went away. The issue only occurred under heavy acceleration, full throttle basically but it was enough to concern my engine builder.
I thought of doing something like you did, I just didn't want to pull a tank and re-work everything. Great work as usual!
Mike

 

[Robert S.]

Robert,
I have a similar engine setup with the same EFI system. My install used a swirl pot in the little box compartment just in front of the rear wheel, the opposite side of the battery box. It is the shape and size of a beer can, maybe a couple inches taller. It is fed with a low pressure, high volume pump and all the excess goes back to the tank. A Bosch 044 high pressure pump pulls off the bottom of the swirl pot and feeds the fuel injection. . . .
Mike

Greetings Mike, I'd like to say again how much I enjoyed seeing your car build evolve. You and Dennis O. did a great job, and the numerous tasty race fixtures and parts installed really make it a gem. I saw a short video of your car at Willow Springs, and I took note of the metal chin hard. Excellent addition! I've been too lazy to make one for my car, but I've had to make minor repairs and paint, which was even more work.

I'm glad you worked out your fuel supply, and found a suitable location for your swirl. I ended up using that compartment for my ECU, High Pressure fuel pump, pre filter, and filter, and all the braided hoses that go with it. I just desired them to be out of view.

Since we live so near to one another, some time this spring or summer, we'll have to go on a caravan together. BTW, did you put a hydraulic lift system in your car as I did? If you did, then we can cruise down to Newport Beach and take the ferry over to Balboa Island.

Let me know if you are interested. Thanks for the detailed note. I enjoyed reading it very much.

All good things, Robert

 

[Tim Kay]

Robert,

Did you consider the Holley HydraMat: https://www.youtube.com/watch?v=yfE1v65fNZI

 

[Robert S.]

Robert,

Did you consider the Holley HydraMat: https://www.youtube.com/watch?v=yfE1v65fNZI

Greetings! Thanks for writing and for educating me to an interesting product. I had not yet heard of that technology.

I believe one would still have to remove and open the tank, and there might be a concern of the float parts becoming tangled or stuck on the baffles, or holes in the baffles. In addition, long term, if the light weight float device or plastic tubing needed servicing, then the tank would have to be removed and cut open again. I did ponder briefly having a removable top door on the tank, but there is very little room on the top for any fasteners, because the tank slides tightly into place, and I worried that one could not screw down a thin top to a gasoline gasket, without being too high, or worse, not sealing out the fuel.

But it's worthy to learn about this, and it may evolve to be useful for small confined tanks with baffles.

All good things, Robert

 

[Tim Kay]

Robert, I believe what Holley says about this unique devise and agree this is going to be an industry game changer. It's ingress and egress will be obtainable through relatively small openings if nessasary and the application will be infinite.

Not quite sure of it availability yet since it's introduction was just last month or so but I'm 'all over it' in the near future.

Tim

 

[Robert S.]

Shock Tower Bridge Discovery . . .

Time Machine Motorsports, LLC
Thank you for shipping A/C and other seals. Check is in the mail.

Rick, here are the picts you requested.

High Def Photos within Power Point Slide Show.

Large file size 18MB

Power Point Slides

 

[Bill Musarra]

Robert,
You might consider the centroid fuel sender.
https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=centroid%20fuel%20level%20sender
This is a great unit in that you can wire it to have a warning lite(or alarm) for low fuel. The fact that it has no moving parts will save you headaches later on. All you have to do is furnish the Ohms range of your gauge.

Bill

 

[Robert S.]

Check Your Shock Tower Bridge

High Def Photos within Power Point Slide Show.

Large file size 18MB

Power Point Slides

 

[Mike]

How did you do that?

 

[Robert S.]

Check Your Shock Tower Bridge

How did you do that?

Maybe "How did that happen" would be a good question, since I did nothing intentionally, or negligently that I am aware of. I would have no motive to do so either.

I was made aware by others who desire to remain anonymous that there are one or more others who spotted signs of this same circumstance, though not as extreme.

I've heard many suggestions by well-intentioned folk within the racing industry. The one that makes the most sense thus far is as follows: The cars were built to original specs, but they were designed for a limited number of races, and the metal was lighter gauge to reduce weight.

Another suggestion was that driving on poorly maintained freeways/roads may be a contributing factor, especially with the 14" wide rear Avons - though I have never driven it off-road and have attempted to avoid the worst highways. While the Avons are huge, they are less than half the weight of my 17" wheels/tires that are steel-belted, even though they are just as wide.

Some have suggested that the h.p. and tq. may have contributed - but then there are others with race engines near to, or beyond my engine's specs, and there was a 1200 h.p. twin turbo SPF too, though it eventually was permanently sidelined due to an accident, there was no report of similar adverse conditions from that car owner.

I would very much appreciate knowing what the proper name of that component is. Some said it is a shock tower saddle. I made-up the name bridge, since it made more sense to me at that time.

 

[Tim Kay]

Robert,

Did you make more than one to sell to SPF brothers?

Tim

 

[Mark]

It looks like that upper cross member was not up to the power. There appears to be a lot of stress on that component. I did not encounter the same thing but in anticipation of that happening, I had a billet aluminum upper cross member machined and the shock mounting plates were done in 5/16" steel plate that are notched into the sides of the billet cross member. Under the ZF transaxle, a flat bar was welded to the clam shell support and an Energy Suspension mount was used to support the transaxle. Lastly, several gussets were welded to the clam shell support to further reinforce the entire structure. If anything, the transaxle will break before the supports.

 

[Mike]

Aren't you running 17s or 18s and low profile tires? And you have it dropped pretty low running close to the bump stops? Not going to be much give with that setup and going to impart shock on the chassis the original race cars were never subjected to.

 

[Robert S.]

Re Designed Shock Tower Bridge

Robert,

Did you make more than one to sell to SPF brothers?

Tim

At the time, I very definitely wanted to. I thought I would just sell them for my cost. However, I did not know what the need would be, if any, and I still don't. I thought too much about it, and then realized that unlike a lot of other helpful pieces many have created for the SPF Bros, this component is a serious structural piece. If an accident occurred that injured someone really badly, or they died, I could find myself defending a suit from the family for manufacturing. We live in such a litigious world now.

My recent intent is to learn if this was a rare individual event, or if others have noticed signs of it. I would never have seen the actual tearing of metal if I had not temporarily removed the two exhaust pipes and silencers to accomplish another project.

Robert

 

[Jac Mac]

I just brought an old thread to the top in regard to this problem in the Transaxle forum. Looks like some of the lessons from the past did not get carried forward to present day.

 

[Tim Kay]

No doubt, when you add liability issue to it then I fully understand and agree. Maybe consider selling the detail plans for the bridge (with a disclaimer!). Seems to be a nice engineered design you have there.

Tim

 

[Robert S.]

Ride Heights, Bump Stops, Rim/Tyre Sizes . . .

Aren't you running 17s or 18s and low profile tires? And you have it dropped pretty low running close to the bump stops? Not going to be much give with that setup and going to impart shock on the chassis the original race cars were never subjected to.

My driving height all around is 3 3/4", and not 4.5".

I have 15" rims that utilize very high profile bias-belted Avon soft rubber slicks from England, which are imported into the U.S., and old school treads are then hand cut into those tires to make the California Highway Patrol happy. The diameter of those wheels with those tires is 26.5".

I have a set of 17" rims with wide low profile steel-belted tires that are also exactly 26.5" in diameter.

Therefore, my ride height remains the same, no matter which rims and tires are in use, and is nowhere near the bump stops.

The other element that surrounds the rims, tires, and ride height that adds some confusion to the subject is my four wheel electric (12 v. DC) hydraulic lift system. When activated, both the front and rear shocks have a hydraulic cylinder directly beneath them, and they lift the whole body along with frame upward nearly 2 full inches.

That combination allows me to ride a little lower than normal, but still navigate speed bumps and troubling road/driveway transitions. It also allows me to ride the Newport Beach/Balboa Ferry with impunity, and I won't attempt to explain just how warm, fuzzy, and happy that makes me and my passenger(s).

The lift system temporarily raises the coil-overs, which in turn lifts the body and frame of the car upward. It takes 15 seconds to travel upward, and 10 seconds to return to ride height, so the action is not immediate or jerky. Since the coil-overs bounce up a down all the time one is driving, and those cycles can be quick or slow depending on the road surface and travel speed, the occasional relatively slow lifting could not possibly cause, directly or indirectly, a shock tower bridge failure of that magnitude.

My facts and thoughts on the subject, Robert

 

[Robert S.]

The Making Process of a SPF Shock Tower Bridge . . .

No doubt, when you add liability issue to it then I fully understand and agree. Maybe consider selling the detail plans for the bridge (with a disclaimer!). Seems to be a nice engineered design you have there.

Tim

Tim,

I'm perfectly willing to share how it was made, as I have already accomplished photographically, but this project is a lot different than one would expect without knowing some extra details.

While I never did see the start, nor the evolution of the failure, I do remember that each time I took my car to a specialty alignment and frame company in Huntington Beach, he would always say that the rear suspension was changing slightly. When I'm using the soft rubber Avons during show season, I always make sure the alignment is perfect. The soft rubber Avons do not wear well when the system is not aligned. They are far less forgiving of misalignment than the 17" steel-belted Michelin tires are.

I did not desire to purchase a new Shock Tower Bridge, so rather than make CAD drawings as I did for the new gas tank design, we used the original Bridge. By that I mean, we made a jig of the current position of my original Bridge, and the position of mounting holes that went through it. Therefore, we created a new one from the original one, even though the alignment of the Bridge was off by a few thousandths. We did this because we knew that once we created a new stronger piece, the numerous alignment points on the SPF could easily be adjusted to get the rear wheels into perfect alignment, and we achieved that goal.

So, making an identical one from my original would mean that installing such on another car would create the need for rear wheel alignment - which would not be unreasonable, but an extra inconvenience and additional cost.

If on the other hand, I had the patience and extra money to purchase a new one, then reverse engineering would result in a CAD drawing of the original. But, I was not willing to wait months for one to be imported from SA.

Hope this explains how the part was made without drawings (plans), but rather from a hole alignment jig, careful measurements, and the tracing of profiles, and not exactly like an original.

Robert

 

[Tim Kay]

Robert,

By your description of the lift system sounds like you have custom length dampers and coils (sorry, have not read whole post if outlined earlier) that allow full compression stroke to travel without bottoming or coil bind, is that the case?

Tim

 

[Keith]

I just brought an old thread to the top in regard to this problem in the Transaxle forum. Looks like some of the lessons from the past did not get carried forward to present day.

Good catch Jac....:thumbsup: