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Wedge Gas Milage on Fuel Injected TR-7

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Sunset7

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Hey guys! Just got the new 80 model cal spec fuel injected 7 running last week, and I have a question:

What kind of highway gas milage should I expect from a fuel injected 7? My 79 carbed car I had about 10 years ago got 27 on the highway, and honest to God it jumped to 34 mpg highway when I installed the Pertronix chip under the distributer cap.

This injected car is barely getting 20 mpg on the highway cruising at 70 -75 mph for almost an hour at a time (daily commute to work)

Any idea on what might be holding it back?
Does this injected model have electronic ignition? Would it benefit from a Pertronix upgrade? (I still have the complete distributer from my other carbed 7 - couldn't I just drop that into this one?)

Lots of questions I know, but I really need to get better mpg than 20 highway since I use this 7 to commute 140 miles round trip to work each day (seriously!)

Let me know!

Thanks!
 
I have a 1980 Cal Spider, and I average 25mpg around town. I've never taken her on a long highway trip so don't know what my mileage would be like there, but I'd have to guess high 20s to around 30.

You most likely have the Delco ignition system. You can tell by the coil...if it's a square coil mounted on the left inside wheelwell (right next to the brake proportioning valve) it's Delco. The distributor has no points, so I guess that means it's electronic. However, that doesn't mean an aftermarket solution wouldn't help it.

Silly question, but have you done a major tuneup on it, including cap, rotor, plugs and wires? Don't forget the air filter (although the EFI ones are rather pricey and hard to come by). You could also check the airflow meter for proper operation.
 
Yes - I have done all the major tune up stuff, just getting it ready to run. I have even replaced the 02 sensor.

How would I go about checking the airflow meter for "proper operation?"

(My car does NOT have the square coil, btw, but that doesn't mean that it hasn't been replaced down the road somewhere - the previous owner and/or his "mechanic" cut alot of wires under the dash in an attempt to fix a bad turn signal switch rather than simply replacing the switch assembly, so anything is possible.

Let me know!

Thanks!!
 
i got 38 mpg on long trips with my '81 dhc when it had the 2 liter fi engine in it. dropped to around 30 mpg around town.
 
oh, and i used a k&n air filter i found along with a foam shim i fabricated to wedge the filter in the air box nice and tight. that helped also.
 
[ QUOTE ]
oh, and i used a k&n air filter i found along with a foam shim i fabricated to wedge the filter in the air box nice and tight. that helped also.

[/ QUOTE ]

You don't have any details (K&N Number) or pictures do you?
 
sorry rich i can't remember the stock number, it went along with all my fi parts to a guy near san diego. i took the original filter to the parts shop and found one the same length the long dimension and narrower the short dimension. carved some foam for a shim and sealed the shim in duct tape.
 
I ordered K&N KNE33-2744 @ $ 38.97 a year ago. It was a tight but perfect fit for my '81 PI

I get 25-29 around town and about 32 on the highway.
 
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