HAI - what's the best temp?

[Project84]

I finally fabbed my heat shield for my HAI yesterday and was at 154*F at 60mph on a 4 hour trip on the interstate.

In the city, I watched as IAT climbed to 178 and even 181*F for a breif moment, but it seems city it's going to average high 170's. Is this best? Is it too much? Should I be shooting for 180*F?

This is in my Saturn SL2 auto.

I blocked off the old IAT tube, cut a hole in the airbox and route ONLY hot air in off the manifold, relocated the IAT sensor to the top of the airbox lid so that it reads very accurately. Using SG to view temps.

PS: I do not mind the reduced power, and yes... you notice it at 170*F for sure.

Sorry if this thread and others like it have already been addressed... I'm really looking for "lovemysan" and/or "cheapybob" to chime in here, or other Saturn owners w/ HAI experience.

Oh yeah... check my gas log for my trip results!!

[GasSavers_BEEF]

WOW!!! your gas mileage went up tremendously.

IMO I would think that as long as your engine doesn't overheat then you are good on the temps. I don't have a saturn but just keep an eye on your coolant temps too. (the scangauge does this well too).

I don't know if you have looked into a grill block but that could help you even more. I think you have made a huge difference in your FE just from the WAI and the scangauge. I remember you saying at one time that your goal was 30MPG. time to raise the bar a little.

[Project84]

Well, to be honest, that was my first ALL HIGHWAY mileage recorded in about a year and a half. I rarely take my car on trips as my g/f loves her Grand Prix w/ all it's add-on's and comforts.

I was expecting 35-36 mpg... like I said somewhere else (Gas saver's w/ record tanks thread) I recalculated the mileage like 5 times and nearly fainted when I was looking at 43 mpg... added the HAI heat shield Sunday morning and SG reported 47.2mpg on the trip home, but I'm going to add some city to it before filling up.

Thanks for the kind words!

I got grill block material from my Dad when I was home over the weekend, it's about 1/8" thick rubber matting. I figured it would hold up to the elements nicely, but I'm not sure it will stretch and hold it's shape and not deform under the pressures of 60mph.

Might be taking the car on a 640mile trip (one way... roughly 1,300 miles total) next week to SC. So my average is going to be way up if I keep reporting 40+.

I must say, I didn't think it was possible... now I'm thinking ANYTHING is possible.

[dieselbenz]

General city driving again. Ambient temps averaging 75*F, changed oil/filter on 7/1/08 31.54

Drive to Cleveland. Air in tires at 50psi, HAI reading 130*F all way there, LOTS of drafting semi's, no cruise control, one passanger, no A/C usage, cracked windows not open all the way. VERY shocked at this mileage... I didn't think it was possible! After recording this mileage, I fabbed HAI heat shield, hoping to get IAT to 150*F+ on highway and 170*F to 180*F in city... results will follow. I just got home, scangauge is showing 46.2 mpg, IAT was 154*F most of the trip home, in city IAT shows 178*F as highest.43.66

Considering the way you drove to Cleveland vs city driving, your mileage is not surprising in the least. I think attributing any of your fuel economy gain from your previous tank to the HAI is unrealistic.

[Project84]

I'm not sure I follow you... before the HAI and SG I couldn't get past 28mpg w/ city driving, now I keep getting 31.xx.

I always have tires at sidewall or a bit higher, but for the trip I aired to 50psi cold, which means, probably 55 psi after warming up. I never use A/C in city, and although I cannot draft much (or at least, it's not very helpful) I coast often, and use neutral when coming to a light. GPH in gear is about 0.48, in neutral it's 0.34.

[dieselbenz]

Originally Posted by Project84

I'm not sure I follow you... before the HAI and SG I couldn't get past 28mpg w/ city driving, now I keep getting 31.xx.

I always have tires at sidewall or a bit higher, but for the trip I aired to 50psi cold, which means, probably 55 psi after warming up. I never use A/C in city, and although I cannot draft much (or at least, it's not very helpful) I coast often, and use neutral when coming to a light. GPH in gear is about 0.48, in neutral it's 0.34.

I'm not saying you're doing anything wrong with your city or highway driving. But i don't see anything in the numbers to suggest that the HAI has improved your fuel economy. Your driving style is pushing both numbers way above epa which is great but the difference between those 2 tanks can't be attributed to the HAI. Your highway mileage with the HAI is 38% higher than your city mileage before the HAI. The EPA highway mileage for your car is 43% higher than city. If anything the HAI has hurt your mileage despite your best efforts.

[Project84]

I'm following you, but it a chasing-my-own-tail kind of way... hehe

I believe I couldn't have done it w/o the HAI... and the fact that it was 43.xx on the way there, then I added the heat shield and got 46.xx on the way back, even though ambient temp was about 14*F higher, it points to one possibility in my eyes... the HAI.

[dieselbenz]

You had a passenger on the way to the airport and I assume you dropped them off and drove back alone. 1 passenger plus luggage can easily account for the 7% difference.

[Project84]

No airport involved in this thread...

I drove there w/ girlfriend and luggage.

Drove back w/ girlfriend and same luggage, plus extra items we purchased and some items my parent's have been complaining I needed to get out of their way since I moved out 3 years ago and left it all there. Probably about 60 lbs extra on the return trip.


So really, more weight on the return trip, higher ambient temps, and average speed of 60mph vs. 57mph on the trip there.

I think that is pretty revealing of the HAI heat shield.

[thornburg]

I thought that warmer ambient temps generally equal better fuel economy?
(aside from running AC or rolling the windows down)