Fitting Small Fuel Tank

[lsdweb]

Hi all
I'm planning on fitting a small fuel tank (1 gallon) in my 172 Cup. It is only used for sprints and hillclimbs. I want to limit the amount of fuel carried for weight purposes.
Anybody done this?
The options seem to be:

• fit in the spare wheel well (which will need a plate with removable cover (for refuelling) over the top.
• cut out the spare wheel well, plate over (like a 182?) and hang the tank and pump underneath.
• Cut through the floor where the existing tank sits, fabricate a box and fit the tank there (covered over).
• Build a box where the passenger seat normally goes and fit the tank and pump n there.

MSA regs apply!
Thanks
Wyn

 

[Mash.]

Heres mine - still got to make a removeable cover for it.

Going to run a filler to a plastic side window with 2nd skin.

Been suggested about rear impacts obvious the tank has no where to go. So possibly might make a rear crash bar behind the bumper.

Sent from my SM-G935F using Tapatalk

 

[lsdweb]

Thanks Mash
Rear impact was my concern too. Using the passenger side of the original location seemed like the best option, a bit like this but smaller and MSA compliant -

Access for refuelling needs to be good as it'll get refuelled before every run (so up to 6 times a day!)

 

[lsdweb]

This looks relatively easy to box in...

 

[Brushwood69]

A friend has a mk1 golf and has a small tank in the back which is inside a metal box to create a firewall between the tank and the cabin

Sent from my HTC One mini 2 using Tapatalk

 

[JACAM]

Anyone know what the oem fuel tank system weighs?


Sent from my iPhone using Tapatalk

 

[Mash.]

Anyone know what the oem fuel tank system weighs?


Sent from my iPhone using Tapatalk

Lol yes [emoji23]

Inc filler pipe

Sent from my SM-G935F using Tapatalk

 

[JACAM]

Kilograms. Ouch. Ta.


Sent from my iPhone using Tapatalk

 

[lsdweb]

Thanks Mash - that's useful!

 

[massiveCoRbyn]

It would be interesting to see the weight difference by the time you're done. Once you've got the new tank in and put a firewall round it, I wonder how big the saving will be. Also worth noting that, unless you mount it right down on the floor pan, then you're moving that weight higher up in the car, which would be a negative.

 

[Mash.]

No worries, so thats my tank, plus 500g for swirl pot, then about 1kg for 2 pumps. Lines wil be similar to standard.

Then about 1kg for box. Other words not a lot of saving. But for me I got most of it very cheap and wanted to stop surge with the swirl pot anyway, so wasnt really about weight saving.

Be more beneficial for the chap above for sure.



Sent from my SM-G935F using Tapatalk

 

[massiveCoRbyn]

So around 3kg saving in you think? As you say, not a huge amount. Depends on the use of the car though I guess. Every little helps, just got to be careful where you place it.

Could you not make a little ally tank and place it under the car, where the standard one is? You save weight but also retain the benefit of it being mounted under the car. Also, as it's outside, you wouldn't need to fully box it in, so it should end up being lighter.

 

[lsdweb]

Some useful info gents. Thanks.

For me the main focus , isn't the weight saving from the tank, fittings although it would be good to make a saving, but the ability to control the amount of fuel I'm carrying around - I have a strong feeling that there is quite a large reserve in the original tank. Running it really low may give starvation issues. So, going to a small tank should allow me to save weight even if the tank and bits are no lighter! I finished second overall in a national championship this year, losing out on first by 12 hundredths of a second, after fourteen rounds and 7 months of racing. So, every little bit of weight loss will help next season!

Wyn

 

[lsdweb]

I forgot to say that my preference is to sit the new tank below the floor in the same position as the existing tank, but just on the passenger side.

 

[Sonic Boom]

Some useful info gents. Thanks.

For me the main focus , isn't the weight saving from the tank, fittings although it would be good to make a saving, but the ability to control the amount of fuel I'm carrying around - I have a strong feeling that there is quite a large reserve in the original tank. Running it really low may give starvation issues. So, going to a small tank should allow me to save weight even if the tank and bits are no lighter! I finished second overall in a national championship this year, losing out on first by 12 hundredths of a second, after fourteen rounds and 7 months of racing. So, every little bit of weight loss will help next season!

Wyn

Which championship do you run in mate?
I've been doing the MHC for the last 5 seasons but I'm going to do the Leaders next year as well.

I've considered doing something with the fuel tank but I run in Road Going Production Class so you can't just start running fuel lines through the inside of the car.
Replacing the original with something small and alloy slung under the car sounds like the best option.

Rich

 

[lsdweb]

Welsh Sprint and Hillclimb Championship. I live in West Wales so my best option. Ran in the road rally class this yet and did ok. Championship is based on class records. Going mod prod next season