2000 Sonata modding project

[menaus2]

Hi all! I've been lurking around for long enough, so I'm finally putting up a thread to document my car's modding projects. I inherited a 2000 Sonata V6 GLS from my grandpa as a graduation gift, so I'm gonna try to see what kind of mpgs I can squeeze out of it.

What I've done so far:
* Tires filled to max sidewall psi
* Removed spare tire, put in can of fix-a-flat
*Installed Ultra-Guage and built a reflective cover to protect it from overheating. Still need to callibrate with mile-markers
* Took out all unnecessary carpet mats (except the driver's)

Planned Mods:

* New Radio receiver. In the middle of replacing the old broken 6.4 lb unit with a much lighter and useful "mechless" unit

*Coroplast undertray. Gonna pick up 2 4x8 sheets in about an hour

*Pizza tray wheel covers

*cover rear wheel wells

*Adjustable lower grill block. Thinking of using a simple lever and bike brake wire setup. Might replace with a servo down the line.

* Side-mirror delete. Replace with interior- mounted convex mirrors.

*Eventually some sort of Kamback, partial boattail or if I'm feeling really adventurous, a full boattail.


Currently getting 28 mpg, better than 2008 epa 20mpg combined, but not that great considering the original epa highway is 28 mpg. The current goal is to get this puppy up to 40 mpg... eventually

[Nevyn]

Hyundai transmissions aren't the greatest at economy. I've got an auto Hyundai myself. DO NOT. I repeat that, DO NOT! ever engine-off coast. Best you can hope for is neutral, engine-on coasting. Unless, of course, you want to guinea pig EOC in a Hyundai and find out what happens. It'll shred the clutch packs.

V6, eh? That'll be a tough beast to break. Coast a lot. Flush/fill the transmission with fresh fluid. New plugs/wires. Coast. My 4-banger Hyundai does NOT like warm-air intake; not sure about the 6's. LOTS of coasting. Upper grille block should be no problem. Check the MAP/MAF sensor (not sure which you have). Did I mention coast a lot?

Rear window aero on my car is HORRIBLE. Kammback/roof spoiler would be a HUGE help.

Best of luck to you!

[menaus2]

Originally Posted by Nevyn

Hyundai transmissions aren't the greatest at economy. I've got an auto Hyundai myself. DO NOT. I repeat that, DO NOT! ever engine-off coast. Best you can hope for is neutral, engine-on coasting. Unless, of course, you want to guinea pig EOC in a Hyundai and find out what happens. It'll shred the clutch packs.

V6, eh? That'll be a tough beast to break. Coast a lot. Flush/fill the transmission with fresh fluid. New plugs/wires. Coast. My 4-banger Hyundai does NOT like warm-air intake; not sure about the 6's. LOTS of coasting. Upper grille block should be no problem. Check the MAP/MAF sensor (not sure which you have). Did I mention coast a lot?

Rear window aero on my car is HORRIBLE. Kammback/roof spoiler would be a HUGE help.

Best of luck to you!

oh whoa thanks for the heads up Nevyn! I usually try and pulse and glide with engine on neutral on the rolling hills where I live. Aero is a huge problem though as coasting time frankly sucks. As far as engine off, would the clutch be spared if you popped it into neutral before turning it off, restarting it in neutral, then reengaging after that?

I'm still hovering around 28mpg as other family members use the car often and a lot of city driving just slays the numbers .

As far as mod updates, the new radio probably shaved a good 5 lbs off the curbweight. I'm in the middle of making the cardboard template for my underbelly and have 2 sheets of coroplast chilling in the garage . Deleted the radio and moved it inside behind the rear seats... not horribly cosmetic but works for the time being.

Still have to see how my Significant Other would handle a kamback or other more visable mods ...

[d0sitmatr]

the problem with an auto trans is that the pump only works while the engine is running, meaning your creating a lot more friction, plus, if memory serves, those trans arent the greatest in the best of times

[Nevyn]

In a manual with a true clutch, engine-off coasting is not a problem (even in a Hyundai). The 'clutch packs' of an automatic are a whole different kind of beast; on top of that, the Hyundai ones are a specialty type as well. They're some sort of non-standard rubber-fiberglass composite. Put in the wrong transmission fluid, and you've got a giant bowl of transmission pudding attached to your engine - the stuff in the fluid (the wrong fluids) can/will/has in the past on folks eaten/dissolved the rubber-ous clutch packs.

If you need tires, see if one size skinnier and one taller is okay. The door sticker on my Elantra says I can use 195/60 or 185/65. Town driving kills on auto trannies. Put car in N, shut down at stop lights. Fire back up as the opposing light turns yellow. That helps to the tune of 2-4 MPG. Even just putting it in N at a light w/engine on gives about a 20% reduction in fuel consumption on my ScanGauge.