grille block/ HAI
 

What kind of gains are people experiencing from these mods? and how much difference do they make in summer vs. winter?

I attribute quite a bit of gain from my grill block and WAI (HAI, whatever). I want to say that I gained 3 MPG from the grill block and another 3 MPG from the WAI. I would have to look back in my gas log.

another thought though is that is also the time when I was learning how to drive more efficiently. there are gains there but I couldn't tell you how much to expect. the summer/winter thing, I couldn't tell you because I have just recently done those things I think in april or may. there again, would have to check my log data.

feel free to check out my garage/gas log to see my progress. my numbers aren't as high as some but I still feel pretty good about them.

I lost MPG from a grill block but that doesn't happen to most on here. With a grill block my mechanical fan clutch almost never gets loose when the engine is warmed up. You can hear that sucker trying sooooo hard to pull air and it can't get enough to cool the radiator to a point that cooler air lets the clutch go. On top of that, because it's trying to pull hard it's loud and sucks a crapton of power building a vacuum.

As for HAI, my car can breathe better up top with the more open intake but I haven't seen it increase fuel economy. This one is driver specific though. I'm not easy on my car, ever. The car spends a lot of time under heavy acceleration and because of that it's in fuel enrichment mode quite a bit(12.5:1AFR) and you can see that with the soot in my exhaust pipe. Having it breathe easier means my top-end power is better but I'm about to build a custom CAI for it because I don't like my loss of torque with the hotter air.

i did a full grill block on my sc1, i was hoping for a more significant result as there was a quite large 'inlet area' on the front of the car, and the radiator only gets air by what the airdam kicks up, but it was minimal, 1-2% better at the most. however, im comparing 55mph commutes, might have a greater impact if someone was runnin 70+ mph down the interstate all the time. as i imagine any good aero mod would act. i would say it definitely hasn't had a negative impact though.

just got my hot air intake in... probably about 150miles on it now, and from what the scangauge is telling me, the hai could boost me around 5%, jury is still out on exactly how much... i've heard the saturns love the hot air more than most, so this may not transfer to other vehicles.

couldnt say winter vs. summer, but i'd guess the impact would be maginally better in the winter.

now that it's winter here in the big city I figured I'd bring this up again. I just installed a makeshift WAI made out of a large aluminum turkey roasting pan and a dryer vent hose. So because I'm impatient, who's seeing much better fuel economy in the winter with a WAI compared to when they didn't have one in past winters?

I didn't keep up with it last summer but the best I could do during the spring was 30 mpg (before I joined the site) and that was about as good as the car got.

here lately, things have been going down hill but I am managing to keep 34 or so mpg even though I pre-heat my car while I am scraping ice on the windshield. I don't attribute all of that to the grill block or the WAI but it does make a difference.

also, I used roof flashing from lowes for mine. it is easier to shape. I am getting ready to redo mine because the temps aren't where I want them. I may have a summer one and a winter one. we will see how it goes

good luck on your project

I only have a grill block. I've done much data recording with and without it.

It's worth about 3.5 mpg or 5% in my car and driving situation. Worth more in the winter, less in the summer.

yeah I drove it from my gf's house to mine this morning expecting to see the temps rise quicker than usual, but it was almost exactly the same. the needle started going up at the same light it usually does. Could it be my setup or does the WAI not actually help it warm up any faster? The way I have it setup is with the turkey roasting pan completely covering my exhaust manifold on the left side of my engine (an inline 4 cyl), then I ran dryer hose over the top of the engine (to avoid exposure to the cold air flowing under the car) and into a foil enclosure surrounding my air filter. Does it need something on the opposite side of the exhaust manifold to keep the air really hot?

From my modified OEM intake, that sucks hot air, I got about 3 mpg better on my '95 VX. I didn't see any gain with the grill block, but the car did warm up to normal operating temp. much faster than normal (about half the time).

In the summer I switched the intake back to normal as it did feel like the car was being "choked" in 90+ degree traffic. With a grill block in the summer you will hear your electric fan turn on a lot more, so I removed it when it got warm to keep the fan from dragging down the alternator all the time.

I have both an almost full grill block (8 square inch opening) and an insulated hot air intake made from hvac ducting and dryer vent all wrapped up in pipe insulation and sealed with aluminum tape. While I didn't really track my mileage to the same degree in previous years I do know that my best summer tank before I did any mods and really started trying was about 44mpg.

I don't really run into any overheating problems, due mostly to the fact that I do very little in town driving, it's almost all highway.

I've made far too many changes over a short period of time to really be able to say how much effect each had, though altogether I'm up about 20% best old to best new.

My last fill, thursday, while disheartening given my summer numbers, was still over 46mpg and it's been cold and windy here (-7c right now). I definitely see the car warming up a lot faster, but the temperature effects and air density changes are costing me 5-6mpg right now.

I perish to think about what my snow tires will do.