Top Speed for an AWD? How fast can it go?

[Midnightsun300c]

I've done 150 and would like to go faster but I have run out of road. I think I may be approaching the limit anyway with it stock. I will try again after my next mods are complete (performance intake, headers, and exhaust). I am hoping to gain 50+ hp and an extra 10-15 mph? I have read nothing on the AWD top speed and would feel a lot more comfortable if there were others that have pushed the limits of the AWD and lived to tell about it! Please let me know what you've done, good or bad with the AWD.

[Big Bob]

Originally Posted by Midnightsun300c

I've done 150 and would like to go faster but I have run out of road. I think I may be approaching the limit anyway with it stock. I will try again after my next mods are complete (performance intake, headers, and exhaust). I am hoping to gain 50+ hp and an extra 10-15 mph? I have read nothing on the AWD top speed and would feel a lot more comfortable if there were others that have pushed the limits of the AWD and lived to tell about it! Please let me know what you've done, good or bad with the AWD.

Hi, I have had my AWD C for about a year and have raced it numerous times at the drag strip, does great out of the hole but need Long Tube headers that are being fabricated (whats up Kooks). As far as top speed I thought the speed limiter was set at 128mph, and you would need to reset it with a comp.chip, anyway I reset mine to 180mph, lets hope I have to raise it some day.

[Midnightsun300c]

Big Bob:
Thanks for the reply. I have the Superchips flashpaq and raised my speed limiter to 180 mph (from factory 125 mph on my car) as well but I don't think I can reach that speed until I do some additional mods. My main concern at this point is how the front end (CV joints etc..) will do at speeds over 150? I wasn't sure how the front end would do over 125 mph until I tried last week. I'm glad to hear that you’ve taken your C to the track...something I have yet to do but would like to very much. How did it run and with what kind of times?

[Rambit]

What speed rating are the Yokohama Parada Spec x tires? The OEM tires are what determines the maximum speed. Hopefully you're gonna say they're at least as good as the SRT8 tires with the speeds you have in mind. I sure wouldn't want a blow out at 150+ mph!!!

Rambit

[B D HEMI]

I've done 130mph in my awd several times , ofcourse the limiters kicked in but anything over 140mph i'm not comfortable with the suspension as she floats quite a bit already and the brakes are CRAP for slowing the car down too !!!
B D HEMI

[Midnightsun300c]

Rambit:
You bring up a good point and a point of growing concern for me since buying the Spec x tire which was my very first upgrade. Before buying my C I looked very hard at the 6.1 but really wanted an AWD so I figured with some prudent mods I could bring a C close to the 6.1. My first stop was a local American Tire dealer and asked what it would take to upgrade to a Z rated tire because I wanted to push the limits of my C. I asked if they made a Z tire for my stock 18” wheels and the answer was no I needed to go to a 20” wheel to get a performance tire. He told me I sure didn’t want a Z tire because I would feel every bump in the road and it would ruin my ride. He recommended a V tire as it would handle any speed I could get with my C. He said that a Z tire was more than I needed because is rated for sustained speed at 170+ mph and I was just looking brief up to 170 mph and back down quickly on a straight road. At the time I had no idea what the top speed of an AWD C was and even if 150 mph was attainable so his explanation seemed logical…but seems less and less logical as time goes on. I was actually surprised after bumping my speed limiter up with the Superchips Flashpaq how quickly I have made it to 150 mph and in hindsight how quickly I have made a dilemma for myself. What are your thoughts on the subject? Is my local tire professional out to lunch? Is a tire’s speed rating an absolute not to exceed for any length of time or is the speed limit apply to sustained speed with cornering?

[Midnightsun300c]

B D Hemi:
Thanks for the reply. The stock suspension issues forced postponing my incremental 5 mph steps up from 100 mph at 140 mph as well. Having the Eibach Pro-Kit installed has significantly improved the handling and all but eliminated the float 140 mph. Having resolved the suspension issues the restraints to go above 150 mph seem to be hp; available safe/secluded/flat/straight road; possibly my tires, and possibly the CV joints? By the way...what does the B D stand for?

[Midnightsun300c]

Update - Installed headers, exhaust, cool air intake and throttle body spacer. Was hoping for a 10-15mph increase but got only half. Top speed went from 150mph before these latest mods to 157mph after. My only venue is a standing 2¼ mile... don't know what could be done with a few extra miles of wide open road? Don’t know if there is a dyno in this State or if dyno exists for an AWD? Seat of the pants tells me that these mods helped the mid-range the most.

In hindsight, reducing the exhaust back pressure and increasing/cooling the intake are two parts of a four part balancing act to optimum performance. The remaining two components are fuel mixture and air flow through the head…tuning and porting/cam/valves/injectors. A bolt on head package with an accompanying computer chip/flash can’t come out fast enough!

My tires are probably too wide, heavy and have the wrong tread for optimum speed...but for everything else but top speed I really like the way they drive. They will probably be retired when the heads are upgraded as they have already been pushed beyond their specs.

The AWD handles very well at top speed with no apparent problems with the current mods. There has been no shimmy, hop, pull, shake or wear problems detected. The mandatory hard braking after top speed has been smooth. After each run a complete visual inspection has been made of the tires, rims, brakes, cv joints, exhaust and engine compartment with nothing to report.

So far it seems that making the room for the drive to the front wheels resulted in shifting things in the engine compartment just enough to make it a completely different car than the 2WD and therefore every modification including the cold air intake made for the 2WD will not work for the AWD without additional fitting and fiddling…beware!

It would be so appreciated if other AWDrs out there that would share their performance mod experiences. I look forward to hearing from you…

[B D HEMI]

Midnightsun 300 , B (bernie) D (dorothy) HEMI - B D HEMI
Thanks for the update on the different mods and the fact that everything is different on these AWD cars vs the rear wheel ones . bernie

[sdiver68]

Originally Posted by Midnightsun300c

Rambit:
You bring up a good point and a point of growing concern for me since buying the Spec x tire which was my very first upgrade. Before buying my C I looked very hard at the 6.1 but really wanted an AWD so I figured with some prudent mods I could bring a C close to the 6.1. My first stop was a local American Tire dealer and asked what it would take to upgrade to a Z rated tire because I wanted to push the limits of my C. I asked if they made a Z tire for my stock 18” wheels and the answer was no I needed to go to a 20” wheel to get a performance tire. He told me I sure didn’t want a Z tire because I would feel every bump in the road and it would ruin my ride. He recommended a V tire as it would handle any speed I could get with my C. He said that a Z tire was more than I needed because is rated for sustained speed at 170+ mph and I was just looking brief up to 170 mph and back down quickly on a straight road. At the time I had no idea what the top speed of an AWD C was and even if 150 mph was attainable so his explanation seemed logical…but seems less and less logical as time goes on. I was actually surprised after bumping my speed limiter up with the Superchips Flashpaq how quickly I have made it to 150 mph and in hindsight how quickly I have made a dilemma for myself. What are your thoughts on the subject? Is my local tire professional out to lunch? Is a tire’s speed rating an absolute not to exceed for any length of time or is the speed limit apply to sustained speed with cornering?

Your dealer is full of SH** for many reasons.

I would not hesitate to push my car to its (I estimate 160) top speed for a few moments on V rated tires.