Ultima Fuel Delivery System Flaw?

[Steve_D]

Slow M said:

What is the theory/benefit to having the filters after the pumps?............

Most pumps do not suck very well so placing a restriction like a filter before the pump is not ideal.
This is also the reason pressurising a swirl pot before the HP pump is a good idea as it helps the fuel entering the HP pump.

Steve

[deadscoob]

I'd personally say if using the factory tanks you must put a filter before the lp pump otherwise it will clog up with swarf from the stuff they use for baffling.

[Steve_D]

deadscoob said:

I'd personally say if using the factory tanks you must put a filter before the lp pump otherwise it will clog up with swarf from the stuff they use for baffling.

I've not had a pump clog up in 17K miles. I suspect the LP pump is of sufficiently low tech and having large clearances that there is no problem.
It's the way the Factory have run them since day one. If there were issues they would have found them by now.

Steve

[spatz]

the last thing you want is that the baffling stuff is reaching the injectors, then you are in trouble

[deadscoob]

Steve I think you have the tanks with the older baffle filling.
The new stuff comes out, a filter pre lp is a must imo.

I can post a photo and you can see for yourself what comes out even at 3k miles with the new stuff.

[UltimaCH]

Any way of removing the brillo pad type swarf from the tanks? Could it be possible to put some baffles in the tanks to reduce surge?

[Storer]

Again Steve is correct regarding restricting the h/p pump.

I have a coarse filter on the inlet to the l/p pump in the tank too.


Paul

[Slow M]

Thanks,

I should have mentioned that I'm asking because I have retrfit a high output EFI SBF V8 into my TVR 2500M, and you folks are well versed in how to build fuel delivery systems.

I suppose, as I am working with a 40 year old tank, I will flush, clean, and re-coat it, and still protect both pumps, as well as the injectors. I won't be using an in-tank lp pump, as I prefer to trade-off a little longevity for digging for parts.

Best,
B.

P.S. Wasn't there a thread on fuel swirl pot sizing math?

[skidiiii]

deadscoob said:

I'd say its worth putting some heat shield by your headers, the nimbus stuff works well

Yes I have heat shield on both tanks as the headers are just a few inches from them. The factory doesn't mention this in the manual but many other builders and common sense would tell you to do this. I have purchased a 50 foot roll of reflective hose insulation to sleeve all the fuel lines. This winter I will unhook them and document the length and fitting, install the shield and post it here for anyone who may be interested.

[skidiiii]

UltimaCH said:

Any way of removing the brillo pad type swarf from the tanks? Could it be possible to put some baffles in the tanks to reduce surge?

Not sure about removing the Brillo pad material. May be possible but sure would be a pain in the neck to get out. Not sure really how effective it is anyway given the amount of it in the tank. A friend of mine just removed both of his tanks in the GTR and used then as shells for FIA Kevlar burst proof bladders. Not a bad idea if you consider racing the car on any track for piece of mind.

[Slow M]

skidiiii said:

. . . I have purchased a 50 foot roll of reflective hose insulation to sleeve all the fuel lines. . . .

Please be so kind as to provide a manufacturer and product name.

Thanks,
B.

[The Italian]

http://www.alamomotorsports.com/thermotec/
Heres one in the US
maybe some suppliers in the UK, try their links of suppliers or have it shipped
Mike

[Slow M]

Thanks, will pick up some of that.

Best,
B.

[crossram]

I have noticed a pattern on this forum over the past six months, owners post about flaws their cars may have and the factory then posts back that they are all incorrect. As a new owner building my car I am not sure where the truth lies.

[The Italian]

Yes, I see the same, although some are older cars where improvements have been made by the factory since their cars were built. I would like to see more involvement with the factory on these subjects.
I know they read it.
Being a F5 owner I have seen some improvements made by the factory BECAUSE of owners stepping up and making their own mods. I am sure it makes you wonder about your build as I also wonder about my very potential build.
My MK2 roadster KIT has changed quite a lot over the years now up to MK4
Some of us just can't leave it alone or finding ways to improve for more HP/handling, like you I am not sure. Perhaps owners also have different purpose for the car than what the factory has built. Rose joints are my pet peeve, I have heard good & bad (for the street), but the factory will accommodate.

[skidiiii]

crossram said:

I have noticed a pattern on this forum over the past six months, owners post about flaws their cars may have and the factory then posts back that they are all incorrect. As a new owner building my car I am not sure where the truth lies.

Congrats on the purchase of a new kit. I hope you are as excited as I was to be be building a GTR. Here is my personal opinion about Ultima and I am sorry if I offend anyone. The first major issue for me was what we refer to as the coloring book of build manual. It has not been updated in many years and as things evolve and change with the car it should be amended to reflect. I offered to make a new manual for the factory if I were to build another GTR just for this reason. I have built 2 now and know them inside and out very well. I have also developed templates on my cnc machine to assist in construction greatly saving time. A few major things I would like to see the factory consider as revisions are:

1) Solid brake lines through the side pod from front to back with flexible terminations that are short. Braided is great for ease of installation however this will fail long before a solid line will rupture. You will notice a bubble in the plastic before it fails, if this is hidden in the side pod and it goes unnoticed you may mash on the brakes and find they are no longer there!

2) Solid line for the clutch as well with short flexible terminations, same as above

3) Fuel system delivery system is way to complicated contrary to the factory's comments. There is absolutely no reason not to link the tanks as so many of us now have. The issues I personally have had with the fuel delivery system should have sparked the factory's interest right away. I have yet to get a clear answer.

4) The baffle material used in the tanks is in my opinion is a joke. I feel as the tanks were being manufactured they could have integrated internal real baffles and it would lead to a much better product. No chance of swarf making its way to the Pollak valve.

5) Fuel filters before the LP pump would be a great addition!

6) A note in the manual or make it standard practice to supply heat shield for the fuel tanks and bulkhead/ rear canopy.

7) Integrating a fuel pressure gauge in the cockpit as I have done to monitor fuel pressure. A very easy way to monitor your fuel filters health.

8) Supply mandrel bent aluminum tubing for the cooling system eliminating all of the silicone with the exception of the connections at the engine.

9) Non factory but worth thinking about.. Make up a plug that houses all engine wires from the ECU to be able to disconnect it right at the engine bay. This way you can simply unhook the plug and pull the engine in short order with out having to remove the entire harness from the engine.

Again sorry if I have offended anyone with my opinions on this matter. I understand it is hard to accept somebody's ideas some time as they are not your own however if it is for the greater good then why the hell not? I feel the brake lines would be a top item and will be retrofitting them in my car shortly. FYI I used all the factory supplied parts and tanks to effectively link mine. I had to order new line and fittings that's it.

These are just a few of my gripes and item I would change if I were to build another GTR.

[UltimaCH]

Good comments and ideas. I didn't know that flexible SS lines had a tendency to bulge and blow out. That is indeed serious and major surgery if needed to be replaced.

[The Italian]

skidiiii
Thank You!
that was a very good summary, and yes brake lines are very important to everyone. My brake lines were trashed from the kit (F5) and replaced w/ stainless(our kits come with pre-bent steel tube, not braid)
Nice to hear a great response like yours. Braid takes minutes while bending takes tools, mistakes and lots of time. Is there not a "split system" in the Ultima ? one fails you still have back up ??front/back

[skidiiii]

The Italian said:

skidiiii
Thank You!
that was a very good summary, and yes brake lines are very important to everyone. My brake lines were trashed from the kit (F5) and replaced w/ stainless(our kits come with pre-bent steel tube, not braid)
Nice to hear a great response like yours. Braid takes minutes while bending takes tools, mistakes and lots of time. Is there not a "split system" in the Ultima ? one fails you still have back up ??front/back

Thanks for the kind remarks. Yes the Ultima has a split system, only the left front could technically be all braid as it is very close to the master. I personally wouldn't want to loose front or back if one were racing on a track, could spell disaster!

[TuxMan]

I have had to upgrade the flexi brake lines on my Noble to solid lines after a brake problem !!!! The main center hose had a bulge in it and the peddle went very soft !! 2003 registered car .
One thing the solid brake lines do do is give you a firmer peddle and much better brake feel .

Tux