Sagarin says take the under, using his various methods none cross 18 points:
15.49 15.21 16.80 17.50
http://sagarin.com/sports/cfsend.htm
Sagarin ranks Tulsa about where all the other models do. 80 - 122 range, but ~100 is where most have Tulsa.
He is a little higher on Houston than most, with Houston at #45, the range is 23 - 79, but it looks like most have Houston around #50.
https://www.masseyratings.com/cf/compare.htm
The Cougs are #1 in the nation for total offense, with most of that coming through the air. My impression is that Tulsa does not have a solid pass defense, but the stats indicate our run and pass defense is about equal (#51 overall, 356 yards per game) - and that we usually hold opponents below their average:
Houston: 608 yards per game
Temple: 357 (300 against Tulsa)
Arkansas State: 471 (402)
Texas: 396 (478)
Central Arkansas: 388 (247)
https://static.tulsahurricane.com/custompages/stats/football/2018/teamstat.htm
While Houston's offensive probably is good and their opponent defenses do suffer a hit to their average, we may be the toughest defense they have played. Opponents defensive rank:
Rice: #115 (opponents have 484 yards per game average)
Arizona: #98 (418)
Texas Tech: #107 (447)
Texas Southern: FCS #110 (492)
Tulsa: #51, 356 yards per game before Houston
http://stats.ncaa.org/rankings/change_sport_year_div
Then again, if they put up 600+ yards, our defensive average will tumble to that 400+ average and rank near 100+ also. If we remove the Houston game, those opponents don't look too dissimilar to Tulsa.
Other factors:
We had a week off. They had a week off. Game in Houston. We have not played the same team to compare. And don't forget the "weird stuff happens when Tulsa plays Houston" factor.
I think Houston will get yards. If we hold on to the ball I think our running game has a chance to control the tempo and limit the points on the board. However, if we give up the ball or become one dimensional and Houston can stack the box, it could become a massacre. 40% chance of rain - which would help us.
The ball hasn't bounced our way for a couple of years. Houston by 21.