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UGH! 48 MPG - What is holding Sippy back?
Topic Started: Sep 27 2009, 09:04 AM (1,820 Views)
starscream5000
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Got 70 MPG?

Mr Murf 59
Sep 29 2009, 06:49 PM
One of the problems for me with the last of the break in for the Rocket is not punching it. I am enjoying not having a worn out engine. I know this will wear off. After a while it will start to go the other way. To sloppy, but that is a long ways down the road. It will get better.
That's how I was brought up to break in a motor:

New oil and oil filter (non synthetic), drive the car gently until fully warmed up, the WOT to about 80% of maximum revs (4th gear in this situation), let off the throttle, do NOT coast in neutral, let the piston rings drag against the cylinder walls as the revs fall, down shift to keep the revs up, once you get in second gear, rinse and repeat a few times.

Do this about 4-5 times, make sure your motor is still staying cool. Give the car a rest, then repeat the process again. Make sure this is done in the first 20 miles of a new rebuild. The whole point is to seat the piston rings properly and it will never get done by babying the car. If it's not done at the very beginning, then it's too late.

Once you've done this around 10-15 times, take her home and change the oil and filter with new (dino) oil. Then baby the car for another 1,500 miles, then switch you oil and filter out again and replace with full synthetic oil.

DO NOT break in a motor on synthetic, you'll not seat the piston rings properly as the oil is too slick. You DO want friction when doing this.
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mwebb
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FOG

rmcelwee
Sep 29 2009, 03:39 PM
mwebb
Sep 29 2009, 12:35 PM
...."about 18+ degrees of crank timing"......


that is probably advanced to0 far ,
what type of fuel are You using ?
87 Octane. Everyone said to advance it until I heard ping. I haven't heard it yet but I didn't go any further than that.
"the advance it until it pings then back it off a little" theory
does not work on my car either .

i have the 3tech cam and the +10 cam wheel as well .
started at 27 degrees btdc base ignition timing and backed off 5 degrees each tank of fuel hoping to see a (yet unseen) improvement .
i am about 10% below what i was before.

using shell 93 octane 10% ethanol NYS blend

right now i am at 14 degrees btdc base ignition timing as per starscream's specification
with speedTracer software i am able to pin the software at the upper limit of 60mpg at steady cruise between 45 and 50mph .

but
that is not relevant
the mileage per tank will show whether or not i have an improvement or i can get back to where it was before i replaced the cam using 87 octane at 8 degrees base ignition timing
...............................
i have requested that the upper mpg limit be raised in SpeedTracer .
the powers that be at AutoEnginuity have promised to increase the mpg max to 75 mpg from 60 mpg in the next release of SpeedTracer , current version is 4.1
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99metro
putt-putt

Suggestions:

45 mph MAX. 40 mph max if you can get a way with it.

Coast A LOT. Make it a goal to coast down to <25 mph before applying brakes at the stop signs.

Shift at the greens for 1st, 2nd and 3rd gears. Moderate acceleration and shift at 3k rpm, or when the pretty green arrow shows up. At 40-45 mph in 4th, shift up to 5th and keep the speed there.

Don't downshift to slow down.

DWL. Drive With Load. Keep a steady throttle regardless of hills. But back off when you exceed 45 mph downhill, or neutral coast down them.

Stay off the brakes if at all possible.
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starscream5000
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Got 70 MPG?

Coast with the motor off while going down hills, this will help as well if you know you can get away with it.
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Murf 59
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Coast with the motor off while going down hills, this will help as well if you know you can get away with it.
Just be mindfull that coasting with the engine off, You will now have to press the brakes harder to slow, or stop. With is not running you have no vacuum to help apply the brakes. And yes I spend a lot of time coasting. Hell if you asked my teachers they would say I coasted my hole life. LOL
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starscream5000
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Got 70 MPG?

Mr Murf 59
Oct 3 2009, 12:26 AM
Just be mindfull that coasting with the engine off, You will now have to press the brakes harder to slow, or stop. With is not running you have no vacuum to help apply the brakes. And yes I spend a lot of time coasting. Hell if you asked my teachers they would say I coasted my hole life. LOL
Actually, you have 2 full brake pumps of vacuum left to use, THEN you run out.

For the distance I coast with the engine off, I do not loose my vacuum assisted braking power.

Try it yourself, get up to speed and shut it down and coast. Apply the brakes, release, reapply, release, then the third time it should be noticeably HARDER to press the pedal down.

If you do not have at least 2 full brake pumps of vacuum left after you shut down the car, then you've got brake/vacuum issues that need to be addressed.
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