Griffith 4.3 petrol hose

[voso1]

I have just changed the rubber fuel hose on my 1992 Griffith 4.3. The correct stated size that I can find is 8mm diameter. I bought the replacement hose from TVR Parts but they sent me 7.6mm diameter. I fitted them on bank holiday Monday as I wanted to get the job done. the grade is 30R9 so that's OK. However I am now wondering if the reduction in diameter will have any influence on fuel starvation or the running of the engine. The metal pipes were not changed only the rubber hoses. it would be great for any comment on 8mm to 7.6mm.

[ianwayne]

Using maths, it's a 9.75% reduction in cross sectional area if your measurements are exactly right. Not a massive change, and whether or not this will affect fuel flow rate I don't know because the pressure produced in the line may be slightly higher because of this?

Fitting new rubber will undoubtedly be an improvement over the (probably) degraded and irregular internal surface on the old pipes.

[phillpot]

The metal pipes are 8mm or 5/16" OD so even smaller bore.

I'm sure the 7.6mm pipe won't be an issue.

[Adrian@]

Cars with air conditioning (I presume later than a 4.3) were fitted with 7.6mm (this addresses the small fittings on the fuel cooler)...just a thought. A@

[voso1]

Thanks to all for replying so quickly. You all made good and worthwhile comments. I can now sleep soundly!!