Another newbie

[cjt]

Just like to introduce myself - I've been reading the forum for a while waiting to get my own Ultima.

Well the waiting is over I am now the proud owner of R200MPH - the Audi engined Sports recently seen on Ebay. Mostly rebuilt by Scott Evered (a lot of engine work by Martin Taylor of Halifax).

Jobs still to do are:

Fuel system, i.e. new pumps and plumbing.
Cooling system including electric backup pump
Charge cooler plumbing
Gear linkage
Handbrake cables
Doors handles and gas dampers
Interior trim
and last but certainly not least surplus engine compartment heat control

My current questions are:-

(1)Which fuel pumps? (at 2 bar engine is estimated at 900 bhp)
(2) The doors have been modified to gull wing style, they don't as yet have any gas struts - anyone have any experience in this ?

It's going to be fun though - hoping to have it running for Le Mans 2006.

I'm based in Marlow for those nearby....

Cheers

Chris

[stig]

Hi Chris and welcome. Just heard from Guy T (bluesatin) who mentioned that you're local - that's 5 Ultima's within 10 miles of me now

As for the fuel pumps, the Carter ones as supplied by the factory should be up to it. 66gph IIRC

Would be very interested in having a gander at the install sometime. Feel free to drop by to compare notes anytime

Cheers
(another) Chris

[bluesatin]

Chris you have mail.

[CanAm Dave]

Hi Chris from a recent Newbie.

I did not see the car on e-bay, so don't know much about your engine.
Reading between the lines I guess its has EFI and a turbo(s). If this is the case you will need a high pressure EFI pump, post and pre filters. If you intend to do any track work then you will need a fuel swirl pot, which in turn will need to be fed by a low pressure pump like the Carter pumps used on the Ultimas with carbs.

On my EFI project I am using my Carter pumps to feed the swirl pot(as above), and then an Aeromotive A1000 pump for the fuel injection. The A1000 can be used for 1000 HP naturally aspirated or 700 HP for forced induction. Aeromotive also supply high flow filters to use with the pump. Demon Tweeks sell these pumps and filters, also swirl pots.

If you need more info just ask!

Cheers Dave

[cjt]

Dave,

Thanks for the info will have a look in Demon Tweaks - the engine is Audi V8 with twin Garrett T68 (i think that's the right number!) turbochargers. The guy who built the engine was going to use twin fuel pumps with filters both sides of the pumps and a pressure regulator at the other end of the fuel rails to return fuel to the tanks. That way the pumps always have a good flow through them. I don't know wether this is normal in automotive circles....

Cheers,

Chris

[Canam Dave]

Hi Chris

That setup is normal for road use! You need to be careful of fuel surge, hence the need for a swirl pot.
FFI pumps have very poor suction, so need to be mounted as low as possible and as close to the fuel tank outlet as you can get. If your not going to use a swirl pot then keep those fuel tanks as full as possible.
The fuel pressure regulator at the end of fuel rails will need to be adjustable to set your base pressure correctly. It will also need to rise on a 1:1 ratio when referencing boost. This is the type I'm installing on my project.

Best regards

Dave

[cjt]

Humm not as straight forward as I thought (why am I not surprised !).....

Ok so since I do intend the odd track moment my fuel system plan (at the moment) is this..

Low pressure fuel pumpfrom both tanks via filters to high pressure pumps (115psi 180 ltr/hr at 3 bar) then via more filters to fuel rails. Regulator from other end of rails returns fuel to the tanks.

Will the low pressure pump help with the poor suction of the high pressure pumps?

Still not sure where the swirl pot should go in the layout above.

Cheers,

Chris

[CanAm Dave]

Hi Chris

Your correct in that the low pressure pumps will help the poor suction of the EFI pumps when you use a swirl pot. The swirl pot is fed by the low pressure pump and then in turn feeds the EFI pump.



In the picture above the main outlet is at the bottom feeding your EFI pump and the top is a vent and the other two are feed from the low pressure pump and return.

Hope this helps

Best Regards

Dave

[cjt]

Dave,

Many thanks - now I understand, presumably the swirl pot is located low down with the HP pump(s).

Where did you get the swirl pot from ? Demon Tweaks have some but they don't look like yours !

Cheers,

chris

[Graham-P]

Hi Chris welcome,
There's a guy called Dave in the Italian Replica Car club(look in the gallery section) whose got a very high spec finished sport with gull wing doors, don't think he comes on here though. I spoke to him at Stoneleigh and recall he came from around the Sheffield area. You might be able to contact him via the site. He didn't build the car but bought it from a guy about 18 months ago.

Graham

[CanAm Dave]

Hi Chris

The swirl pot in the previous pic is from Car Buider Solutions and it costs £89.

The one I have is from Demon Tweeks and is made by ATL, item 16 on page 245 of the current catalogue part No. ITC305 costing £127.50.

This is the one I have.



Cheers

Dave

[pb3]

Graham

Interesting that car at Stoneleigh as I believe it was the example built by Barry Edge who I know sold it some time back. Why it was in the Italian Replica Car club I have absolutely no idea! It took him 10 years or 10000 hours can't remember which and was featured in a kitcar mag years and years ago.

[Alan 2]

cjt said:

Dave, .... The guy who built the engine was going to use twin fuel pumps with filters both sides of the pumps and a pressure regulator at the other end of the fuel rails to return fuel to the tanks.... Chris

If you intend to run twin tanks and twin fuel pumps with EFI, then you have to make sure that the "overflow" fuel from the regulator is returned to the tank from which it is being pumped. If you don't, there is a real risk of overfilling the other tank and pumping fuel all over the floor. This is most likely to occur after you've just filled up and the engine is idling as most of the fuel being pumped is simply going around the rail and then straight back to the tank.

I have EFI on my AS engine (not yet on the road) and have just been researching this particular point. Allen-GTR has faced the same problem and his advice has been very helpful. Thanks again Allen.

There are a couple of ways you can get around the problem. One is to return the "overflow" fuel to an upside down "T" piece on the rear bulkhead and then install a solenoid operated valve in each of the fuel lines between the arms of the "T" and the tanks. Jaguar have done this in the past (old XJ12's had twin pumps and tanks) and I have the part number of the valve they used, if anyone is interested. These valves would need to be linked to the fuel tank changeover switch so that when, say, the left side tank is being used, then the left side valve is open and the right side valve closed. However, there is some doubt about how restrictive this particular valve might be when fuelling an Ultima and until somebody tries it, we won't know for sure.

The other way is simpler but requires a manual input and this is the route I have taken. My fuel tanks are linked via one of the standard dash 6 connections at the bottom of the tank. The other bottom connections feed two high pressure fuel pumps through pre-filters and then via a final filter to the fuel rail.

"Overflow" fuel is returned to an upside down "T" as described above and then via shut off valves to the top connections of the tanks. Both fuel pumps and both shut off valve are linked to warning lights on the dash (red for the o/s and green for the n/s). So if fuel is being pumped from say the n/s tank, then the warning light for the n/s pump and n/s shut off valve will both be showing: ie two greens. Ditto for the o/s but two reds. If I get one red and one green, then I'm in trouble. It does mean manually changing the shut off valves when I switch tanks but if the tanks are linked, switching tanks is not something that needs to be done very frequently. I have two tanks (linked) and two fuel pumps on my Sports and normally switch over about every couple of weeks when I think about it. Of course, if you have only one pump pulling from one tank, then there's no real problem, that is if you're happy to rely on one pump. I've had two pump failures on my Sports, one when I was in the outside lane of the M25. Very unsettling.

On the subject of auxilliary pumps and swirl pots, I've just looked out the info I received from AS on setting up the fuel system for EFI. It says "...Do not run fuel through any auxilliary fuel pumps or reservoirs (collection tanks). Run a line from each tank to a "T" and then into the fuel pump. Keep it simple. Other methods may cause fuel starvation".

Sorry this is such a long spiel, a picture or two would have been much simpler.

[Graham-P]

Phil
Yes that's the one, Barry moved to Spain I believe, the guy has made some changes mainly to the brakes (HiSpec) and now has Ultima lookalike wheels from Image IIRC. He used to own the white Lambo that was next to it at Stoneleigh, plus before the Sports he had that yellow GT40 that was dripping with all the chrome etc. I guess that he was a member of the Italian Rep Club with the Lambo so stayed with them. The Sports though is a really well finished car, the interior alone would be a match for any production supercar.


Graham

[cjt]

Graham,

Thanks for all the info - will try to find where the car is now.

Cheers,

Chris

[cjt]

Alan,

Thanks for the reply - further to what I said earlier I have since spoken to Martin Taylor (who did all the engine intakes,intercooler, ECU wiring, charge cooler etc etc).

His view was that double fuel pumps (unless either was capable of full power fuel flow on it's own) would leave you open to lean mixture (and catastrophic overheating) in the event of a single pump failure. Mounting one large Aeromotive pump low down (so that it is self priming) was his suggestion. The is provision for the ECU to sense fuel pressure and control pump operation in the event of an 'adventure'.


I hadn't yet considered the situation where one tank would feed back to the other....

Cheers,

Chris

[cjt]

Alan,

Just one further thought....

Red is normally on the left (as in the saying "port is red wine"

Just wondered....

Cheers,

Chris

[steve_D]

cjt said:

Alan, Just one further thought.... Red is normally on the left (as in the saying "port is red wine" Just wondered.... Cheers, Chris

Another way to remember it is:-
Red, Left & port are all the short words.
Green, Right & Starboard are all the long words.

You want useless info I'm yer man.

Steve

[bluesatin]

I have concerns flying as a passenger with somebody who does not know left from right!

[Alan 2]

cjt said:

His view was that double fuel pumps (unless either was capable of full power fuel flow on it's own) would leave you open to lean mixture (and catastrophic overheating) in the event of a single pump failure. Chris

Chris, I have two identical high pressure (50 psi) pumps which operate independently, not together. These are mounted horizontally and as low down on the rear bulkhead as I could get them. They are just about level with the bottom of the tanks so priming them shouldn't be an issue.

You're right about the warning lights. I sometimes struggle to remember which is right and which is left. so I'll change them around and try and remember Steve D's advice about all the short words etc.