Author Topic: Tyre Pressure for HPE  (Read 8633 times)

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Offline Fulvia 3

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Tyre Pressure for HPE
« on: November 20, 2015, 12:19:41 PM »

Happy owner of a 1978 HPE 1600 since last month.
According to my Instruction Book, inflation pressure should be 24 psi !!
[27 psi when full loaded and 28 full loaded and constant high speed.]
According to a 1976 North American specs Instruction Book, inflation pressure is 28 psi (sounds logical).
For the first month I tried 27 psi and she drives nice. I cannot persuade myself to try 24 ....
What is your experience on the subject?

Thank you,
M

Offline HFStuart

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Re: Tyre Pressure for HPE
« Reply #1 on: November 20, 2015, 01:01:28 PM »
Maybe 24 on the back when empty but seems too low.

What tyre size?

I run 185/65 14 with 29psi all round (in a spider) and it works well.

Offline smithymc

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Re: Tyre Pressure for HPE
« Reply #2 on: November 20, 2015, 01:24:02 PM »
My handbook says the same for the coupe - I now run 26 all round one or two up on standard tyres.

Mark

Offline Fulvia 3

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Re: Tyre Pressure for HPE
« Reply #3 on: November 20, 2015, 02:24:30 PM »

Offline HFStuart

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Re: Tyre Pressure for HPE
« Reply #4 on: November 20, 2015, 07:17:35 PM »
Reckon 27 all round would be about right then.

Offline Neil-yaj396

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Re: Tyre Pressure for HPE
« Reply #5 on: November 21, 2015, 08:05:50 AM »
The pressures in the handbooks always seem to be on the low side by up to date standards.

Offline lbcoupe76

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Re: Tyre Pressure for HPE
« Reply #6 on: November 21, 2015, 09:14:29 AM »
You have to take into consideration that every tyre manufacturer will have different sidewall construction and therefore different pressures. Tyres have changed a lot since those tyre placards where written. Look up the rule of four for tyre pressure, this works well. if you can't find it i will type it out for you.
1976 Beta coupe 1800 "Kermette"
1975 Beta coupe 1800 x 2
1974 Beta Berlina 1800
1989 Thema i.e turbo
1988 Thema i.e turbo
Fiat 1500



Smoke me a Kipper i'll be back for breakfast

Offline peteracs

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Re: Tyre Pressure for HPE
« Reply #7 on: November 21, 2015, 11:07:20 AM »
You have to take into consideration that every tyre manufacturer will have different sidewall construction and therefore different pressures. Tyres have changed a lot since those tyre placards where written. Look up the rule of four for tyre pressure, this works well. if you can't find it i will type it out for you.

Good call, I had forgotten about that. Here is what appears to be a good write up

http://cdn2.hubspot.net/hub/210453/file-20229690-pdf/docs/importance_of_optimum_tyre_pressure_and_temperature.pdf

Peter
Beta Spyder S2 pre F/L 1600
Beta HPE S2 pre F/L 1600