Wai
 

My old '88 Escort has the old heat riser system on it where has the duct from the exhaust manifold to the breather to help with warm up time, so a few weeks ago I decided to set it up where the trap door would stay open all the time, allowing heat from the exhaust to enter the breather constantly. The only problem with doing this is that on warm days in town the temperature of the engine rises a lot faster than it did before. Since doing that I've had fill-ups at 46.748 mpg, 41.976 mpg and 44.199 mpg. On the tank that got 46.748 mpg we also had really nice temperatures several days in the 70 and lows in the upper 30's and 40's. The next tank the temperatures were pretty cold, we also had some snow that hurt FE and on the last tank most of the morning temperatures were in the lower to upper 20's with high's in the 40's and 50's. I've been very happy with the results that it has yielded. The two higher mpg tanks are at or near what I usually get during the summer. I'm hoping to be able to run this way during the summer without any overheating problems. If I can there's a good chance I can break the 50 mpg barrier.

Sounds promising... Maybe I should try forcing the trap door open on my Buick as well...

-Jay

It's worth a try. You'll never know if you don't experiment. I was expecting some benefit, but the results have been better that I was expecting.

So this is kind of like a WAI straight from the factory? I'd love to see pics of how they set it up.

What I would do is bypass the thermostat for the flapper, and connect it straight to engine manifold vacuum, so if the engine is running, the trap door is always closed. Now I just gotta get my lazy butt to take the air cleaner assembly apart to do it.

-Jay

Here's a good page to look at to understand how it works...

https://www.autozone.com/az/cds/en_us...rInfoPages.htm

hmmm... I noticed that this is on a carb engine. Are there any factory WAI systems on FI engines?

Some of the early fuel injection systems also had a similar system. Almost all carbed engines had a system like this.

hmm thats odd, when my chevettes stuck open all the time i got crappy milleage, like went from mid 30's to low 20's... i should probably get a new one but thier $12 last time i checked. I gotta remember to get one off a junkyard car next time....I just disconnected it for now and back up in the mid 30's

Is your vette computer controlled, or non-computer?

non, full blown normal carb. the 83+ vettes did tho (crude one but it worked kinda)

The reason I ask is that my 81 Regal has that POS computer controlled carb in it.

Can it be worse than the Quadrajet in my '80? I'm pretty sure it's not computer controlled...and in fact I'd say it's not controlled at all.

Yeah, my Regal has a computer controlled DualJet. I had a standard QuadraJet in my 1980 Bonneville Safari, and that went over 200,000 miles without overhauling the carb, and didn't have any problems either.

-Jay

My Escort is throttle body injected.

The Bonnie's carb has a much better record than my Buick's neglected carb. I would be surprised if it doesn't need a rebuild and all its problems are actually from vacuum lines and such.

I'm quite sure my Bonneville and your LeSabre have the exact same carb in them. Does your car have the BIG orange terminal block mounted to the inside of the fender for connecting to a crude early computer diagnostic machine? If so its equipped with the same carb & controls that my Bonneville had.

I was wondering what that thing was. At least, I assume I was, because I already have a photo of it in my online album:
https://lh6.ggpht.com/_oNsRR_T1Qx0/SB...0/IMG_0649.JPG

My carb is awful. It's ridiculously difficult to start the engine cold; you have to crank it for 45 seconds or more while rapidly pumping the gas pedal through its whole range, from foot off all the way to the floor. It idles way too fast, except on the rare occasion that it idles properly or stalls...and other complaints that I can't remember.

It's just old and rotted. I need to rebuild it. The last (and first) time I rebuilt a carburetor was over a decade ago in high school shop class, and I think I rebuilt a chainsaw carb and a carb from a 5hp Kawasaki. Who knows, maybe I could do the job...

Yeah, that's it. You can rebuild that one, or a rebuilt one shouldn't cost too much if you offer your current one as a core. The last time I had to do something to the Buick's carb my mechanic recommended a rebuilt Rochester DualJet rebuilt by Holley. It wasn't cheap, but he said that at least you know that people who know carbs did the work. He said that Trak Auto and Pep Boys carbs are hit or miss.

-Jay

Well after bragging about how well my Escort was doing since I rigged up a warm air intake. We got about a 5 inch show and temperatures in the 10's for lows and 30's and 40's for highs. I can tell by the gas gauge I'll be lucky to break 40 mpg this tank. I can't wait for summer.

At least I still broke 40 mpg on this fill even with the snow and very cold weather it came in at 40.211. At least very cold for the Carolina's.

Well, I'm excited. Today when driving I noticed my IAT was 110F. Hasn't been that high in a while. I was so excited I've started shutting the truck off at red lights again (Plus, I don't need the heat like I did lately).

I hit 206f today and man did I have no power but the milage was great....

Yeah, I've heard that over 190F was "bad", but nobody has ever gone into detail as to why. Maybe its because the power drops off too much after that point? I should experiment in The Beast, as that has pleanty of power to spare.

-Jay

I'm going to leave it as is till this tank is burned up or I throw a code then I'll add some cooler air to the mix

I recently started running a WAI type system in the Durango and I can say I've found yet another car in which it doesn't work. I made a trip to El Paso 1/17/09 and got 16.03 mpg there and 14.65 back. Since the elevation in Albuquerque is a good 2000ft above El Paso getting better there and worse back makes sense to me.

After the removal of the snorkel intake air temps runs about 100 degrees above ambient(as opposed to the only 20-40 with the cool air snorkel) and this weekend I went there and back yielding only 15.71 and 14.22. That's a .3mpg drop there and a .4 drop back. Same speeds both time, same ac usage, same speed as verified by PCMScan, and I used the same pumps. The first trip had more city mileage mixed in with the freeway time. It wasn't much warmer outside either, maybe 15 degrees difference between the trips, this last one being the hotter of the two.

The cold air snorkel went back on today. This is my second vehicle to loose mileage with the introduction of warm air intake. The Tracker had a mass-flow EFI system and this one is speed-density. What are you guys doing differently to make your vehicles get better mileage with warm air?

A couple things that could be happening that come to mind are that maybe your detonating with the higher IAT's and your knock sensor is retarding the timing .Or possibly if you don't have a separate baro sensor the fuel mixture is slightly off going to different altitudes. A few things could be happening with the change in altitude actually. maybe its not the best test environment to prove the mod as not working. Another thing that comes to mind is your egr. I don't think egr knows the exact combustion temps or EGT, but it might somehow be opening more. I'm just throwing out ideas here. I don't know exactly how your computer system works.

Knocking is possible. The first time I'd ever heard that thing knock it did after the WAI was in use going up a mountain.

My 360 isn't equipped with EGR.

so it did knock with the wai. if its knocking at all it would probably be a good idea to take it off. or try a higher octane fuel. It would be interesting to see the mileage with higher octane. In theory a higher octane burns slower though, which would throw of the optimal timing programed into the computer from the factory. Pretty sure there's no way for a computer to know what octane your using.

My last fill came in at 46.708 mpg although it was only a 5.879 gallon fill I know it's accurate because the tank was filled to cap at the beginning of the tank and refilled to the cap. I'm really curious to see what this is going to do for engine temperatures during the summer, I'm wondering if it's going to cause the engine to run too hot. If it doesn't effect engine temperature too much it should yield some good numbers this summer in 90-100* weather and summer blend gas. The worst fill I've had since using the WAI is 40.211 and we had about a 4" snow and temperatures in the teen's and twenties during that tank, but I've had 2 tanks at over 46.7 mpg. Right now the current tank is looking really good, but the forecast is for about 4 days of rain so I'm pretty sure that will have a negative impact.

that was a concern of mine too so I've been paying attention to my water temp . I have good news it appears IAT has no affect on Coolant temp.

Refilled again yesterday after 300.5 miles and took 6.275 gallons of gas to refill. 47.888 mpg with about 100-150 miles of that driving being done in the rain. Seems that if I can use this set up during the summer months I should be able to break 50 mpg in local driving.

I'm loving this WAI. Since I started using it mileage is usually running 44-47 MPG on the '88 Escort, and Monday I was going on a venture that was going to be very little stop and go, so I filled up and checked my highway mileage. No error, because I filled the tank to the cap both times. The car got it's best mileage ever of 52.446 MPG. The distance driven was 132.9 miles (by the odometer) with a fill of 2.534 gallons of gas. I also had my GPS in the car and it showed 137.7 miles on 2.534 gallons which comes out to 54.340 MPG which is problably correct, but I've been going by the odometer ever since I started my gas log so I guess I'll just keep posting it that way, since sometimes I forget to turn on the GPS and wouldn't always have an accurate mileage. I think it would have been better had it all been interstate driving, but about 50 miles was 2 lane roads with a couple small towns with traffic lights, but I was able to time out most of the lights getting stopped by only about 4-5 lights. I was driving 50-55 MPH on the two lane roads in the rural areas and 55-60 on the interstate stretch. The best I had ever got before was 50 MPG on about a 700 mile trip several years ago driving 55 MPH and all interstate.

That's great to hear...

I've noticed the same thing the only time it seems to warm up faster than before is in stop and go traffic, then I notce the temperature gauge seems to rise a little bit faster.

Jay, I think I've read some of your post stating that you have some older cars. Do any of them have the heat riser system? If so you should try wedging the door closed so that all you get is warm air from the exhaust manifold and see what the results are in your case.

Yeah, The Buick and Rusty both have the thermac WAI on them. Unfortunately the Buick rarely gets driven long enough to really warm up, so I don't think it would make much of a difference. I think my greatest gain would be getting the torque converter to lock again.

-Jay

this was "tried" (not to my knowlege) on my 1980 chevette. wow did it not liek it... the temp "sensor" thought it was freezing all the time so it kept the flap wide open to the exhaust shroud and blocked most of the ambient air intake part.

i only noticed when my gas mileage bit the dust hard. at that time i was getting 28-31mpg when that thing decided to keep it open the next few tanks were barely 25-26mpg...was reading a general car maintince book and listed a table of things that could decrease mpg. that was one of them.

i dunno if it was because it was a major air restriction or not (at 55-60 mph its runnin 3k rpm so its suckin alot of air) so i took the temp sensor out and put duct tape over the 2 small holes it had. Been like that for 2 years now. starts fine in the winter, idles fine, but under a load it runs funny and you have to baby it when its still cold. once it warms up a bit its fine.

I had also wondered before I tried it whether it would act as a choke on my Escort and hurt mileage. If your Chevette is not FI, I bet with it sensing the engine was cold it was also closing the choke causing the poor mileage. My Escort is TBI, so it doesn't have a choke.

Yeah, that's another thing to consider... WAI / HAI doesn't work on non computer controlled or primative computer controlled cars because they aren't smart enough to lean the car out when the IAT gets really high...