basically, say the 4 runners average 2 minutes in an 800m race, how much slower would a 4 x 8 relay be? Also, if anyone wants to comment on other events where there are time differences like that, that would be cool too.
Like,
100m v. 110h
400m v. 400h
4 x 400 v. the 4 people's cumulative 400 times
3,000 v. Steeplechase
2 Mile v. Steeplechase
its not smart to assume that the relay would be slower. you have to consider factors during the race where they averaged 2:00 and see how they carry over to the relay. example-what was the competition like? things like taht could make the relay splits be faster
A common mistake is to add up the PRs of the four relay members and assume that is what the relay team will be able to run. It's rare that all four runners will run in one particular race as well as each has at any other point in their careers. Like the other poster said, how far off is difficult to speculate about because the answer is different for each runner and each race situation.
For the 4x4 take off 1/2 sec per runner, that should be a good estimate. For 4x8 1.5 sec. Usually the runner's 2 mile time is close estimate to the steeple time depending upon hurdling ability.