At what speed should the speed limiter be set at?

 

because of those bigger tires, your speedometer is "OFF"!! Please be careful around cops or when driving over 50 as you're really going faster than that. A great defense but the cop usually doesn't buy it I think the speed limiter kicks in around 95-100mph so instead of the 80 you think you're doing, you're actually closer to 100mph. Check with your service dept to see if they can reset your speedometer. And do look into the superchip, it will get rid of the top speed limiter and give you a whole lot more hp too.

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2000 F250 Crew Cab 4x2 6 speed Diesel XLT Super Duty, Woodland Green
Power Mirrors, 3.73 LS, Captains Chairs, ARE tonneau top, mud flaps
Trailer tow Pkg, Class IV hitch, sliding rear window, running boards
rear privacy glass, 265/75/16 AS OWL tires, am/fm/cassette/cd
Clarion APA 5240 amp, Memphis speakers:Components front, 5x7 rear, 10"sub
SuperChip, Stepshields, Ventshields on windows, rubber bed mat
rugged liner bedliner on tailgate

 

Some have claimed there speed limiter (actually isn't it really the rev. limiter? Anyone?)was kicking in at 81 or so MPH but like Tina and I said you are going faster than you think! I was under the impression it was tied more to the engine RPM than the Actual vehicle speed so it would kick in different speeds for different trucks depending on the effective gear ratio.

 

My understanding of this (and it aint much) is that there is both a speed limiter and a rev limiter. I believe the superchip takes out the speed limiter and ups the limits on the rev limiter. This is difinately a question for Mike though!!

 

The speed limiter is different from the rev limiter. My parents have a 95 f350 that is off by about 5-7mph @ 70. They have 35inch tires. Just so you know about the difference in speed you get.

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2000 F-150, XLT, 4X2, Ext. Cab, S/B, 4.6L, 3.55 L/S, Tow Package, Premium Sound CD Player.

Future Mods: NONE, I'm broke.

 

I have a 98 F150 with a 4.6L engine. The tires are have on are 1 inch bigger than standard equipment. Recently I was on the highway and using the MILE MARKERS noticed that I would do about 1 mile and 1 to 2 tenths for every mile marker.
When I picked up speed somewhere around 80mph, the truck would jerk and not let me go any faster.
Could the tires be causing this jerking action?? Is it something else??

 

No it's not the tires, its the computers top speed limiter kicking in. Because of your larger tires your speedo is off and you are going slightly faster than you think. If you want to remove that speed limiter investigate the use of a Superchip. Go to dealers forum and ask Mike Troyer about it.

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97 F-150 SC Lariat, Styleside, White over Gold, 4.6L (Windsor), Automatic, 3.55 rear end, electronic 4X4, w/ every option of Lariat and ORP packages except the 17" wheels (I even got the OR decals now!) MOD's so far: K&N air box mod, Gibson Super Truck, clear Bugflector II, Leer TSC 600 hard cover, Bridgestone Dueler OWL ATP 265/75 R-16's, TrailMaster Invader N7 shocks, Smittybilt step bars, Ford moulded mud guards, "White-white" head lamps, Cloud Rider Design's SS Grill and bumper opening, Bosch Platinum + 4's, Hayden 30K+ Tranny Cooler,Class III Reece load distributing hitch system, full wiring including trailer battery charging system, Escort Sensor II Brake controller, Superchip

 

First, YES ABSOLUTELY 100% YES tires CAN AND DO effect PREFORMANCE!!!! They have one of the biggest effects on vehicle performance!

(performance means: handling, traction, gearing, etc..)

Secondly, I have NEVER heard of a 80 MPH limiter???? I have a 98 Expedition and I think it cuts out at 100!

More than likely, you have some other sort of unrelated problem. Maybe the limiter is kicking in at the wrong time! A tire ONLY 1 inch larger does NOT make that much of a difference. With larger tires the limiter would still cut off when the speedo reads 100 (or the stock cut-off setting), however, you would in reality be traveling faster than 100 MPH because of the size difference...

I'd have it checked out!



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Rand

 

Here's a formula for you...

New tire diam/Old tire dia * indecated speed = real speed.

so... 31/30 * 80 = 82.6. Also 31/30 * 55 = 56.8.

Not much of a difference. Hopefully you won't get a ticket for 1.8 over. You're top speed limiter is going to be working on that "real speed", so it will cut off sooner than normal by the speed indicated on the speedo. There was a thread that turned into a flame fest about the top speed limiter cutting in too soon. The problem was solved by resetting the computer(disconnect battery, turn on light to draw any residual current out, reconnect after 10-15 minutes) which had somehow got confused. Couldn't hurt to try.

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1997 F150 XLT Flareside
4.6, Auto, 3.55, custom catback
Pioneer DEH-305, Alpine 3547, 12" Kicker Comp.

 

The speedometer reflects the speed the computer thinks your vehicle is moving.
It has no way of knowing the difference between actual spped and speedometer speed becase computer speed and speedometer speed are both dirived from the driveshaft.

 

I read through several threads and found that Jim814 had the same problem I had. He called it an "82mph CHUG". I was experiencing the same thing, disconnected the battery, resetting the computer, but the problem came back.
Well I called Mike Troyer at Superchip and described my(our) problem. He told me that my tire diameter was one inch larger that the standard equipment. When I was doing 80mph I was actually doing 87, etc. MORE IMPORTANTLY the larger tire was screwing with the VSS or Variable Speed Sensor. He suggested that I either go back to original equipment(my thought already) or he could configure a chip to straighten out the speedo misread or some similar techno solution.
So Jim814 if you are out there. The tires may be causing your problem. Once the VSS chip is no longer being confused you should return to normal. The speed limiter, according to Mike, is between 98 and 108, but usually closer to 98. ALSO the speed limiter is ABRUPT and shuts off fuel NOW. Mike says it is quite a rude and possibly an unsafe way to activate a speed limiter.