MPGs run, Aspire SE

[TominMO]

There's an apples-and-oranges aspect to this too. Matt's customer reporting 7 MPG increase was driving a carby Festy; so different cam and different fuel system. Plus I regard his results as more anecdotal than mine, simply because I don't know anything about his methodology. Also, the carby system has less ability to adapt than an EFI system, which may have helped in some way; i.e., the full increase came immediately.

I would consider my tests to be Matt's practical testbed for the Aspire MPG roller cam. I don't consider the 1.4 MPG improvement to be inconclusive, just minimal; plus, it may improve with less timing, and the computer "learning" the new fuel parameters. He said I just need to drive it around for awhile, then look for results.

[mikeyjd]

There's an apples-and-oranges aspect to this too. Matt's customer reporting 7 MPG increase was driving a carby Festy; so different cam and different fuel system. Plus I regard his results as more anecdotal than mine, simply because I don't know anything about his methodology. Also, the carby system has less ability to adapt than an EFI system, which may have helped in some way; i.e., the full increase came immediately.

I would consider my tests to be Matt's practical testbed for the Aspire MPG roller cam. I don't consider the 1.4 MPG improvement to be inconclusive, just minimal; plus, it may improve with less timing, and the computer "learning" the new fuel parameters. He said I just need to drive it around for awhile, then look for results.

Good thoughts.

[TominMO]

Here is a summary of all my Aspire MPG tests, so you don't have to go flipping back to find them:
Aspire SE mileage testing synopsis
(All tests done at 60 MPH except the first one)
....MPG.......Description
A. 45.0.......stock; 185/70x13 tires; 55 MPH; approx 250 miles
B. 55.0.......small front air dam, same tires; 100 miles
C. 52.7.......larger air dam, side/rear wheel skirting, 165/80x15 front tires on steelies; 155/80x13 snows on rear; 100 miles
D. 59.7.......larger air dam, side/rear wheel skirting, 185/70x13s on front, 155/80x13 snows on rear; 100 miles
E. 51.3.......larger air dam, side/rear wheel skirting, 155/80x13 snows all around; 100 miles
F. 54.0.......as above but with new 155/80x13 Kumhos @44PSI, removed wipers and mirrors; 243 miles
G. 53.3.......Kumho tires, reinstalled wipers/mirrors, removed all side skirting and added kammback; 176 miles
H. 51.2.......kammback removed, back to front airdam only, cleaned and balanced injectors; 220 miles
I. 52.4.......as above + Dickmeyer Aspire MPG cam; 241 miles

You're right mikeyjd, a 1.2 MPG difference between H and I.

Tests B through E should not be taken as seriously since they were only 100 miles; more of a chance of skewed data due to fill errors. However, except for D, all results @60 MPH fall between 51.2 and 55.0 MPG.

It just occurred to me that all these tests have been done with summer gas! Maybe just switching to the winter blend will give me 10%, which I have seen in the past.

Hopefully I will get Matt's FPR and header installed before Madness; and for the trip, I am thinking of going all-out with rear wheel skirts, kammback, wiper/mirror delete.

[TominMO]

It just occurred to me that all these tests have been done with summer gas! Maybe just switching to the winter blend will give me 10%, which I have seen in the past.

Oh wait, I have that backwards don't I?

[TominMO]

Oh wait, I have that backwards don't I?

That's right, schmuck. Get with it.

[TominMO]

That's right, schmuck. Get with it.

Hey! Language!

[FestYboy]

you so Ca-razy!!!

[getnpsi]

I personally think you should go up to 150 miles on computations, however the more data you get the less important if the trends follow the mods, traffic speed and weather conditions

[mikeyjd]

Oh wait, I have that backwards don't I?

Si

[TominMO]

Was curious about the unexpectedly low MPG number of my last run, so I went outside and looked at the cam timing again. Yup, off a tooth. It was retarded one tooth, therefore about 7 degrees. This was masked by having the ignition timing advanced 3 degrees; and with the cam profile being different, maybe it tolerated the discrepancy more than a stock cam would have. But I don't know. Anyway, I corrected the timing and will do a run this week, possibly as early as tmw. I set the timing at 10 degrees BTDC.

[TominMO]

Just took it for a run to see what's what. At 10 degrees timing with the cam sprocket lined up properly, it seems to have about as much power as with the stock cam. If I can pull some good MPG numbers too, it will def be the "best of both worlds" cam, because I know I can add more timing for more power, with only a slight loss of MPG, if any. I will go back to increasing the timing after this next run, to try to find an optimal timing for MPG.

[Pu241]

When do you suppose you slipped a tooth on your timing?
Do you suppose any of the previous runs were afffected?

[TominMO]

When do you suppose you slipped a tooth on your timing?
Do you suppose any of the previous runs were afffected?

No, this happened when I put the new cam on, so it only affected the one test. But it's interesting that I got as good a mileage as I did (52.4) with the cam off a tooth!

[1chrisapple]

That's right, schmuck. Get with it.

u said it hahaha

[mikeyjd]

Well this is good news. I look forward to seeing if correcting the cam timing makes a difference.