vaporstang

Here is a link to some field tests on Mobile 1 and Amsoil:

http://neptune.spacebears.com/cars/stories/mobil1.html

This link takes you to the Mobile 1 write-up and the menu on the left will take you to the Amsoil write-up plus other information. I don't know how scientific this is - they did use Blackstone for some of the tests. (It's been a while since I read this.)

mygt500

I have power all the way to 6500 RPM with the Whipple and if I had bought gears tomorrow it would still be the 4.10's. I researched many times for the past yr and talk with many from the car club and driven in one with FI and 4.10's and it was impressive to say the least. Also I would probably run a fat 20" tire on the car like the Invo's which come in 40 series so a taller tire will effectively lower the gear anyway right? (meaning it will act like say for example 3.90's). I also have the rev limiter set at 6800 RPMs so I too would not be worried about running out of gear in fourth at the track...... JMO and sorry back to the topic at hand

mygt500

So really what is the difference between the 20W or 30W and for everyday use in the warmer months of the year how would it impact the car if any? Why did Ford recommend the 20W? any info appreciated and the previous debates were dizzying

Riptide

IMO go ask the question on bobistheoilguy. That site deals specifically with motor oils.

Short answer is that they recommended it for fuel economy reasons. There are ideas floating around that the tolerances are tight enough on the engine that 20W is actually good for it. But no real proof and when you consider Saleen and Roush recommend 30W that doesn't appear to hold up to scrutiny. 30W may be better for your engine if you beat the hell out of it at a race track. A spirited DD and an occasional drag strip car isn't probably going to benefit much form 30W oil.

Lots of opinions, no scientific testing on a large enough scale to truly prove much of anything. Pick your poison. 20W and 30W are both probably going to be fine 99% of the time IMO. 20W is required for complete warranty coverage.

mygt500

Thanks Riptide!

Stkjock

no they are not too much. 3.73 are better for the highway.

It really depends where your car lives and how you drive it. If your a drag racer - DON'T FEAR THE GEAR

Don't doubt, get the 4.10s

/\ very good description IMO, Argonaut is specifically talking about road racing. With long straights were one could hit 125+, I agree 4.10s are not a good choice. One way to balance the shorter rear gear is a taller tire as Jason mentioned, it will effectively take some gear away. If your not looking to run the car at those speeds, or trap the 1/4 at 120+, 4.10s are the best bang for the buck mod you could do.

As far as 4.10s and FI - / thread.

buster

A few years ago, Consumer Reports did a test on NYC taxi cabs putting different types of oil in identical cabs. They ran them for 6,000 mi between oil changes (to accelerate wear) and what they found was that motor oil protects and engine the same from one brand to the other (excepting synthetics). Synthetics are great if you have a vehicle which runs allot of miles (ie cabs, pizza cars etc). But you must factor in the additional cost of the oil. Consumer reports concluded that the only difference in oil is price and additives. In other words, they said buy the cheapest oil you can find, it protects the same as the most expensive. This also includes bulk oil you get a Quickie-lube.

As far as weights go, do what your owners manual says.