Datsun Roadster Forum-311s.org

I'm going to build a stainless steel gas tank for my roadster SR20 swap, and I currently plan on using a vent/roll over valve like this one:
http://www.speedwaymotors.com/Fuel-Tank ... ,5848.html
mounted higher than the gas inlet, and will feed this from vent port on the Holley fuel pump system I'm going to use:
http://www.speedwaymotors.com/Holley-12 ... 66514.html
Is there any need for vapor canister to remove gas smell beyond this? Anybody ever retrofit a vapor recovery system in an engine swap?

Second ?. Since I don't have a roadster gas cap right now, is the stock roadster gas cap able to be pressurized like newer cars if I seal off the vent fill tube, and only use the vent/roll over valve to relieve pressure?

Lastly, I'm thinking of going with a universal sending unit like this one:
http://www.speedwaymotors.com/Stewart-W ... ,7848.html
This is not the Datsun's range for ohms, which won't be a problem if I go aftermarket gauges, but can the factory fuel gauge be modified to work with this range (240-33 ohms)?

Thanks for your thoughts.

I used a charcoal canister for vapor recovery and tucked it into the well space on the right side of the trunk. I use a non-vented parts store chrome gas cap. It works well and does not smell like fuel.
As always, YMMV

if your not going the purge valve and control unit to operate it route
you could still encorporate the carbon canister ,but it is not going to work as a evap system
watch opening the cap in summer if it holds to much pressure
modern caps hold .02 hg vac and hold .07hg pres ... less than 1lb pressure Mitsu specs anyway
I am trying to build a tank plastic for my 86 Z31 T or find one that will bolt up .... who wants to build a SS gas tank for you ? ..for pass. car .. the liability thing,... he is responsible for it for ever

Unless I'm mistaken, the gas cap for a 70 is not vented, might fit the bill
I don't know about the liability, if you ask someone to build something to your specs, I would think it's your problem to determine the suitability of the design and materiel. Plenty of people make custom gas tanks for things like boats and T buckets.

I just finished an aluminum tank, and used a Speedhut sender - and Speedhut gauges. Their fuel guage will work with any sender, but you might think about gauges before picking a sender, Autometer, etc are different ohm range than stock datsun (GM).

Michael

+1 mlwebb
Step 1. Pick your gas gauge
Step 2. Choose the sender that is compatible with #1

It will definitely work.

dbrick wrote:Unless I'm mistaken, the gas cap for a 70 is not vented, might fit the bill
I don't know about the liability, if you ask someone to build something to your specs, I would think it's your problem to determine the suitability of the design and materiel. Plenty of people make custom gas tanks for things like boats and T buckets.

It's your problem until its someone else's, like a accident and it goes to court . I gave up on getting many a aluminum project welded ,as the guy I used has a slew of ?s usually saying "l have to pass because of legal reasons"
There was a court case where a guy modified his Cessna seat moving it back because he could not fit in it stock .
he crashed the plane because the seat came loose braking hard & was killed
Cessna pointing it out he modified it ,not their fault . The jury though awarded the plaintiff millions
Cessna quit producing small aircraft under 1/2 million $ soon after
As long as it is in use the producer/ maker is liable

As far as the liability, it will be me building it, so I don't have to worry about getting someone to do it.

redroadster wrote:As long as it is in use the producer/ maker is liable

And this is why we cannot have nice things..

Found this one on ebay after we realized my original tank was not worth saving. Excellent construction and it even came with a nice high pressure pump. Ebay seller is "simtecmotorsportssales" in Farmersville Texas. Gauges are all stock modified so factory sender still used which keeps the system very accurate.
Jon

Jon
Can the stock gauge be modified to work with a different sending unit?
Thanks

Havent seen one yet that works with the stock gauge so we purchase the gauge that matches the sender and then swap the guts behind the stock face and install it into the stock roadster case.
Jon

Jon
thanks for answering the question. So I'll ask one more! I'd like my tank to support any potential gauge, so I wanted to design it with the same size hole/location independent of the ohm range. The Tanks Inc sending units seem to fit this requirement:
SW - SW gauges - 240-33 Ohms
VDO - VDO gauges - 10-180 Ohms
GME - GM up to 1964 - 0-30 Ohms
GML - GM 1965 and up - 0-90 Ohms
ORG - Early Ford & Mopar - 73-10 Ohms
http://www.tanksinc.com/index.cfm/page/ ... prd276.htm

I've read in older posts that the Roadster is ~83-10, yet others have used a 73-10 from a VW Bug. Can the 73-10 sensor work with the stock Datsun gauge? If so, I've found my solution.

The total resistance value is less critical than the ratio of the arm with regard to the total value. In other words since the stock roadster gauge reads from 83-10 ohms the middle reading for half would be would be 50% or approx. 41 ohms. The same would go for any sender like the VW unit so as long as the half full output is approx. 36 ohms then it will most likely work. (I say most likely because I have not specifically tested the VW units but have seen others mix and match using this formula and other than some minor tweaking it works fine.)

Hope it help

Jon

[quote="caraddict"]Found this one on ebay after we realized my original tank was not worth saving. Excellent construction and it even came with a nice high pressure pump. Ebay seller is "simtecmotorsportssales" in Farmersville Texas. Gauges are all stock modified so factory sender still used which keeps the system very accurate.
Jon


I looked for him, no could find. Did he have only the one SS tank or does he make them?