Lotus Elan

Historic Sandown 2011

PostPost by: rgh0 » Sun Nov 06, 2011 10:27 am

A few photos from Sandown. The car ran well but sufferred a loss of power for a few seconds in the each of last 2 races up the back straight under full power and 8300 rpm. I think a fuel restriction / blockage maybe from the foam in the fuel cell starting to break up and blocking the pump or filter. Time to strip it out and replace it I think.

cheers
Rohan
Elan 2011 Sandown 1.jpg and
Elan Sandown 20011 2.jpg and
Elan 2011 Sandown 3.jpg and
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PostPost by: twincamman » Sun Nov 06, 2011 1:23 pm

CHECK TO SEE IF THE VENT TUBE FROM THE TANK ISNT KINKED OR BLOCKED ENOUGH TO ALLOW THE AIR TO BE EQUALIZED in the tank --- CAUSING A vacuum IN THE TANK OVERCOMING THE PUMP-DRAWING CAPACITY at high revs or the hole may need to be enlarged --or the gas cap vent hole may need enlargement -ed
dont close your eyes --you will miss the crash
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PostPost by: ardee_selby » Sun Nov 06, 2011 4:10 pm

rgh0 wrote:A few photos from Sandown

8)

rgh0 wrote: ...under full power and 8300 rpm. cheers Rohan


Wahooo! What's that in real money? Diff ratio= ? mph = ?

Also what are the wheels? (They look a bit JAP Magna-ish)

Cheers - Richard
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PostPost by: twincamman » Sun Nov 06, 2011 4:27 pm

In racing it's "how fast do you want to go and how much money do you have..ed
dont close your eyes --you will miss the crash
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PostPost by: ardee_selby » Sun Nov 06, 2011 5:43 pm

twincamman wrote:In racing it's "how fast do you want to go and how much money do you have..ed


Ed, usage was an expression...like:

"The capacity is up to 606 cubic feet, I have no idea how much that is in real money, will we get all our stuff in?"

"Radians! What?s that in real money? 5 rad = 5 x (2?/360)? and 90? = 90 x (360/2?) rad"


Cheers - Richard
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PostPost by: elansprint71 » Sun Nov 06, 2011 8:47 pm

Full power and 8300 rpm or full throttle and 8300 rpm? :wink:

Now I understand your avatar.
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PostPost by: rgh0 » Sun Nov 06, 2011 9:57 pm

twincamman wrote:CHECK TO SEE IF THE VENT TUBE FROM THE TANK ISNT KINKED OR BLOCKED ENOUGH TO ALLOW THE AIR TO BE EQUALIZED in the tank --- CAUSING A vacuum IN THE TANK OVERCOMING THE PUMP-DRAWING CAPACITY at high revs or the hole may need to be enlarged --or the gas cap vent hole may need enlargement -ed


I have a fuel cell with a separate vent line and check valve. i will check that line also when i pull the tank to make sure it is clear and the check valve is not stuck shut

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PostPost by: rgh0 » Mon Nov 07, 2011 10:10 am

ardee_selby wrote:
rgh0 wrote:A few photos from Sandown

8)

rgh0 wrote: ...under full power and 8300 rpm. cheers Rohan


Wahooo! What's that in real money? Diff ratio= ? mph = ?

Also what are the wheels? (They look a bit JAP Magna-ish)

Cheers - Richard


3.77 diff I use as it is a good average for the circuits I race on.
rev limiter set at 8300 rpm and change up on the limiter
Can hit 8000 rpm in top using 175/60 - 13 tyres - around 200kph on the main straight at Phillip Island if no head wind.
The fun bit is just touching the brakes and taking the right hander at the end of the straight at 180kph :D
You go a long way before you stop if you get that corner wrong !!!!!

The wheels were made by a local company called Performance Wheels back in 1979. The company still exist and makes alloy wheels for companies like Harley Davidson as well as local car companies such as Holden and Ford and Toyota.

cheers
Rohan
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PostPost by: rgh0 » Mon Nov 07, 2011 10:10 am

ardee_selby wrote:
rgh0 wrote:A few photos from Sandown

8)

rgh0 wrote: ...under full power and 8300 rpm. cheers Rohan


Wahooo! What's that in real money? Diff ratio= ? mph = ?

Also what are the wheels? (They look a bit JAP Magna-ish)

Cheers - Richard


3.77 diff I use as it is a good average for the circuits I race on.
rev limiter set at 8300 rpm and change up on the limiter
Can hit 8000 rpm in top using 175/60 - 13 tyres - around 200kph on the main straight at Phillip Island if no head wind.
The fun bit is just touching the brakes and taking the right hander at the end of the straight at 180kph :D
You go a long way before you stop if you get that corner wrong !!!!!

The wheels were made by a local company called Performance Wheels back in 1979. The company still exist and makes alloy wheels for companies like Harley Davidson as well as local car companies such as Holden and Ford and Toyota.

cheers
Rohan
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PostPost by: elj221c » Mon Nov 07, 2011 10:43 am

rgh0 wrote:The wheels were made by a local company called Performance Wheels back in 1979. The company still exist and makes alloy wheels for companies like Harley Davidson as well as local car companies such as Holden and Ford and Toyota.


Pleased to hear that Rohan. I would have been concerned if they had been JAP-ish as Richard and I first thought. JAPs are very fragile and I suspect that you wouldn't pass scrutinering with them, especially here in the UK. I remember a well known tyre emporium refused to fit new tyres to my JAPs back in the late '80s unless I signed a disclaimer. The wheels were less than 20 years old then but he must have had a bad experience with them.
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PostPost by: prezoom » Mon Nov 07, 2011 4:49 pm

I had the same problem with the engine getting soft or loosing power after a long straight at high rpm. Turned out to be the float needle valve was too small. With the low fuel pressures, and standard jetting, the engine was sucking the float bowls dry. Switched to 200's and the problem disappeared.

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PostPost by: rgh0 » Tue Nov 08, 2011 12:04 pm

Cut up the fuel filter I changed out and no sign of blockage from fuel cell foam - back to square one in terms of theories :?

Dont believe its the Weber float valves size being to small as these have been fine for many years on this track.

Maybe the fuel pump has a problem with leaking valves so not putting up its usual flow and pressure - need to do some flow and pressure tests i think on the pump.

I have been running the fuel a little lower as I try to add lightness and it occured on the last lap both times on the 2 Sunday races. I have had around 7 to 8 litres left in the fuel cell at the end and maybe that is to low given the quick series of left / right / left / right corners before the main back straight.

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PostPost by: twincamman » Tue Nov 08, 2011 1:36 pm

could be the diameter of the fuel line -----you could be over coming the flow capacity -the foam in the cell will stop dry sumping the pick up --ed
dont close your eyes --you will miss the crash
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PostPost by: SJ Lambert » Wed Nov 05, 2014 7:24 am

I'll say G'day on Saturday if I see you in the paddock Rohan!
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PostPost by: rgh0 » Wed Nov 05, 2014 7:51 am

Yes I will be there see you in the paddock. Just finished putting the Elans front suspension back together as I had it apart for its routine 2 yearly crack testing. I discovered a slightly bent bottom thread on the RH upright where it goes into the trunnion and cracks were just starting to form where it was bent. I suspect I bent it at the last meeting where I was punted off and went over the curbing sideways and backwards

I realise I never posted the answer to the problem I had. I discovered there was a filter inside the electric fuel pump that was blocked with fine rust particles coming through with the fuel. I must have put the pump in 15 years before and never checked this filter as I never knew it was there ! Its now on my annual check list :D

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