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Posted by: mzapisek Apr 10 2019, 08:00 AM

I'm running 245/50/16 on the back and 225/55/16 fronts with GT steel flares. Tires look good and perform well. I do get rubbing on the inner fender well at full lock. I am using a 1/2" spacer in the front.

I have a spare set of 16" front wheels. If I go with 205/55/16 to reduce the section width the tire diameter reduces by almost one inch to 24.9". My current set up has almost identical tire diameters at 25.7".

Is there a problem with running smaller diameter tires in the front? Handling? Alignment? Would this create to much rake?

Appreciate some input. I searched but couldn't find a definitive answer.

Thanks.

Posted by: dr914@autoatlanta.com Apr 10 2019, 08:03 AM

I would go with the narrower diameter, makes turn in better and actually makes the handling better as a result (also the steering is lighter)

QUOTE(mzapisek @ Apr 10 2019, 07:00 AM)

Posted by: roblav1 Apr 10 2019, 07:30 PM

Personally, I'd go with narrower fronts, as George said. Lowering of the front by 0.8" will slightly increase rake, decrease caster, and generally contribute to more oversteer. You don't say what your current spring rates are or front and rear ride heights (or ARBs). If you're happy with the way the car currently handles, lower the rear slightly (if adjustable spring perches) or raise the front at the torsion bars.

IMHO, 205 front and 225 rear aspect ratio is right for flared 914. And 15" wheels are better than 16" wheels because of the lower rotating mass. Wider tires don't necessarily equate to better grip. Other factors play in the mix, particularly tire compound. The 914 is so lightweight anyway... they don't need the bigger tire sizes.

If you eventually swap out tires / rims, here's a general methodology for car setup:

- Set tire pressures
- Set ride height / rake
- Set corner weights
- Set caster and camber (I prefer more front caster in 914 / early 911)
- Re-check corner weights
- Set toe
- Re-attach adjustable ARB links

Posted by: mzapisek Apr 11 2019, 08:32 AM

George/Rob I appreciate the input. I have ordered the new tires and look forward to trying them out. Thanks.

Posted by: larryM Apr 16 2019, 10:46 PM

you don't tell us what ET or backspace your wheels are - or what brand

- nobody can give you a credible tire recommend without that info

check fitments yourself here
http://www.rimsntires.com/specspro.jsp

Posted by: Dougal Cawley Apr 18 2019, 08:34 AM

Hi

i think you are making a mistake with 16" wheels. it will drive better on a ,more suitable tyre off here. https://www.longstonetyres.co.uk/classic-car-tyres/porsche/914.html

However if you really want 16" wheels these will be the best

https://www.longstonetyres.co.uk/pirelli-collezione/cinturato-p7/205-55yr16-pirelli-cinturato-p7-n4.html

https://www.longstonetyres.co.uk/pirelli-collezione/cinturato-p7/225-50yr16-pirelli-cinturato-p7-n4.html

https://www.longstonetyres.co.uk/pirelli-collezione/cinturato-p7/245-45yr16-pirelli-cinturato-p7-n4.html



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Posted by: mzapisek Apr 18 2019, 08:39 AM

Wheels are Fuchs standard 911 offset. Went with the 205's up front. Much lighter steering feel and eliminated the rubbing. Very happy. Thanks for the input.

Posted by: Rleog Apr 19 2019, 07:50 AM

Hmmmmm
Nice tread pattern. Pirelli’s?

Posted by: Dougal Cawley Apr 23 2019, 06:09 AM

QUOTE(Rleog @ Apr 19 2019, 02:50 PM)

Posted by: burton73 Apr 23 2019, 04:52 PM

Your tire size is fine for the front. You just add a part from Elephant called “Tire Rub Prevention Kit”

https://www.elephantracing.com/suspension/911-steering-related/911-tire-rub-prevention/tire-rub-prevention-kit/

This will stop the wheel from turning too much when you turn the wheel all the way. Really you only go that way when you are parking or moving it

I have one on number 41


Bob B