Is your Maurauder really that quick in the 1/4 mile?

[stumpy]

Well if you're running on a set of 18" rims I bet not! To make things worse on yourselves, you've gone with higher rears gears, which multiple torque and cause even more uncontrollable spin.

Here's the deal. None of the serious weekend warriors, in Cobras, Vettes, Camaros, you name it are running big rims. They all know it's a losing battle. I'm sure there is a fancy theory out there about inertia and a spinning wheel to support this, but I know what I see and I see everyone going small. I met a guy today with an 11 second Z06 vette, he says his friend gets it into the 10s, that came stock with 18" rims. What does he run, 16"s with ET steets.

I started talking to the Mustang and Cobra guys, all running 16" rims with slicks (Ford makes one hell of a rear end). I asked, what is the bolt pattern and how big is that rim. It turns out that although Ford switched to metric sizes on some cars, the late model (2003) Mustang/Cobra rims are still SAE. I did some checking, very un-scientific mind you, and it appears that the Marauder rims are the same as Mustang rims, 5 x 4.5".

What does this means and where am I headed? It means that you aren't limited to 7" wide rims or modified 18" rims to get a bigger patch. After market Mustang rims are plentiful and easily acquired in sized from 15 x 8 to 17 x 11.

What to do next, first off verify that your bolt pattern really is SAE and is 5 x 4.5". Second, figure out what is the widest rim you can mount based upon back spacing. Better yet, if you know some Mustang ppl then meet them at the track and talk them into letting you test fit them on your car. If they do fit then see if they'll let you make at least one pass with them on. Heat them up real good and launch full tilt and see what happens.

The bottom line is this, good traction not only makes you quciker, it makes you so very much more consistent. If you're not consistent you're most likely going home early so give this a try. I'm looking forward to hearing the good results.

[Directedby]

Ummmmmm......

[RCSignals]

Are you suggesting people have been less than truthful about the times they've posted?

If not, man these Marauders must be scary with 16" rims :)

[DetGeno]

Obviously stumpy have never stop by one of our many local, regional or national events. Or else he would of never asked this question! We welcome any and all SS owners to our exciting functions or if you are ever in the Metro Detroit area give us a heads up for an interesting advanture!

[SergntMac]

Hey Stump, I appreciate your effort to bypass the art of science we tend to cherish, but I think it's got less to do with the calculations, and more to do with availability. ET streets are not available in 18". Moreover, my 28X11.50X17 ET Streets are 28" tall, thus matching my 28" tall rear tires, so, I'm not really gaining or loosing anything, circumfrence-wise. Keep in mind too, that driving on ETs with radial front tires, requires a touch of skill at the 1/8th mile marker. Can you imagine driving on jello?

[JET]

Originally posted by DetGeno
Obviously stumpy have never stop by one of our many local, regional or national events. Or else he would of never asked this question!

Stumpy was at 2 events that I was at including Atco & Englishtowne. He knows track talk. He first ask me this question after he saw my car spin out of controntol several times. My answer was :confused:. So I asked him to ask the question on our forum. "Thank you Stumpy".



1-Know again if we run a smaller wheel with a taller tire that is the same combined height as our OEM why wouldn't it work?

2-Why is our offset so different than the norm?

[Smokie]

stumpy The title of your post can read two ways, one you may be suggesting that the existing times for our cars are not truthful; the other is that we could be doing much better by going to smaller diameter rims and perhaps you are also suggesting that taller gears are counter productive.
I believe after careful reading, that the latter is where you are coming from. So here is my opinion as the owner of an MM. with a reflashed PCM (improved soft shifting) and otherwise all stock car.
My new car has seen the track twice after rolling the odo about 7k. This car for most of us is a daily driver and we love the way it looks the way we bought it. going to 16" rims may produce better E/T's but unless the owner wants to turn his/her car into a race car, void the warranty and no longer have a car that looks like the MM. it makes no sense. We have owners already that are committed to speed and the only thing at this point that is keeping these cars from 11 sec. is having a set of rears that will hook-up, the power is already there. Most owners on this forum don't want a race car, they want the beautiful car that they own to have a better response from a dead start and this issue has already been addressed with very modest modifications, my car runs the 1/4 mid 14's with lost of traction, has the potential for for low 14's "as is" and is everything I wanted and more, It does very well for 4200 lbs and it looks the way I bought it; that is how I like it.:)

This is my opinion, and I do not wish to imply I speak for the rest of this club.

BTW I agree with you that better traction makes better E/T's and is also safer (I almost hit the damm wall this weekend)

[TripleTransAm]

The 16 inch issue is an easy one. Besides the very valid point regarding availability, it's also a sidewall issue.

Think of all the folks running stupid-low pressures in the rear to get a better contact patch during that crucial moment of launch. The reason certainly isn't to cushion the launch lest we spill something stored in the trunk organizers... it's to allow the sidewall to flex and s-t-r-e-t-c-h the contact patch to as long as possible. This is sometimes a futile exercise on modern stiff-sidewall radials, by the way, but sometimes every little bit helps.

So by using a 16 inch rim with equivalent ride height, you've got more of that height in sidewall and not in unbendable rim. Add to this the designed-for-launching sidewalls on drag radials and / or slicks, and you get the sidewall wrinkle necessary for ideal longer contact patches during a hard launch.

I gotta admit, along with everyone else I also was taken back by the subject line on this thread upon initial sighting. I pretty much thought this was an attack on the veracity of our 1/4 mile claims. Given that the last time I checked (this morning) I was satisfied with the size of my pecker, I don't believe I'd need to artificially inflate my car's performance for the sake of compensating for some male inadequacy. So, yeah, I reached into my desk drawer and was busy assembling my shiny new flamethrower as I read through the thread... luckily, the point of this thread came through quick enough.

Perhaps a better way to initiate this kind of thread would have been to say "is your Marauder as fast as it could be..."...

[Smokie]

Perhaps a better way to initiate this kind of thread would have been to say "is your Marauder as fast as it could be..."... TRUE

[Constable]

Given that the last time I checked (this morning) I was satisfied with the size of my pecker, I don't believe I'd need to artificially inflate my car's performance for the sake of compensating for some male inadequacy.

HAHAHA ROFL


Stumpy, I know exactly what you mean. Everyone else: stop over-analyzing... he's right about the smaller wheels and he obviously meant no disrespect to you.

To add to TripleTransAm's post about smaller wheels and bigger sidewalls, I'd throw in a few key terms like "rotational mass" and "unsprung weight". I'm no genius in these departments (as it will show) but I would figure that a smaller wheel equals less weight & size - mass - that would have to be pushed around... wasting time and a tad bit o' power.

So the question is still this: will a 16" mustang rim bolt right up??? Cause I'd love to throw a set of sticky's on and head to the track.

I know Dennis had that set of Cobra R's on the blue MM...

[stumpy]

/coughs into fist and clears throat

Sorry, I was drunk and it was late!

/hangs head, kicks the dirt and walks away

:lol:

First, let me restate the title "Make your Marauder quicker"

Second, I only had good intentions and my sole purpose was to get the community thinking about a more suitable drag racing setup for getting traction out of the hole. Therefore, I'm really addressing the Drag Racing crowd here, the ones that intend to run more than a few weekends a year.

I think TripleTransAm made my point in a much more articulate manner, thank you sir. Hopefully someone will take this and work on an optimal setup for this HUGE aspect of drag racing. In my brief experience with drag racing, nothing registers more in the SOTP dyno than lowering my 60' time. Likewise, I'm seeing more than .20 reduction in ET for each .10 reduction in 60' times.

Lastly, if I ever pick up a Marauder I don't want to have to do all this research myself. Instead I want to be able to pick the ultimate package like I did with my Impala due to the fact that others spent 7 years sorting out what works and what doesn't. :D

HTH

[CRUZTAKER]

:up:

[stumpy]

One more thing, you get a better patch by putting a larger tire on a small rim so don't get crazy on the width, the point is to get a wider tire not the widest rim. I run 275 x 50 x 15" on an 8" rim and I'm getting consistent 1.70 60' times. Atco pic (http://davemilcarek.com/112203/pages/11-22%20R-3%20006.htm)

Also, these are not my daily driver tires, I bolt em on at the track.

[TripleTransAm]

No worries, Glen... by the time I was 3/4 through your post I pretty much figured what you were trying to get at.

Constable, good points about the wheel mass and how it's distributed. The overall mass, I can see being a benefit if the rear wheels are smaller overall, reason being that I'm not sure what's heavier... the wheel or the rubber on it. Whichever is heaviest will colour the argument from then on. (ie. lots more weight around the edge of the wheel, or concentrated in the center, etc...)

One thing is for sure, the moment of inertia of a 'disk' (pretty much our wheel/tire combo) changes with the way the weight is distributed across that disk. The further out the weight, the greater the moment of inertia. Those of you with desk jobs and swivel chairs have surely tried to spin yourselves around while seated on the chair, and noted the difference in rotational speed as you extended your arms and legs and subsequently retracted them. (pretty cool trick, but don't try this after lunch).

If we're talking shorted overall wheel/tire combos, then there's another benefit that someone mentioned in another thread... the change in effective gear reduction. As far as how much torque gets to the wheels, all the driveshaft cares about is how many turns it has to accomplish to get one rotation of the wheel. If you go with a shorter wheel/tire, you'll need more rotations of the driveshaft to get the same vehicle speed. This is an increase in gear reduction, and subsequently an increase in torque multiplication at the contact patch. Sort of like the equivalent of going with a 3.73 rear gear instead of 3.55, all by changing the height of the tires (using the example from the other thread).

[TripleTransAm]

Just a side note to all regarding your tire size selection post...

One cannot blindly say a certain size tire will properly fit on a certain size rim. While there are ideal rim / tire combos as far as width goes, how much you can deviate depends on the tire construction.

With a too-large tire, the sidewalls will tend to bow inwards to the rim edge, and depending on the sidewall construction this *may* end up lifting the edges of the sides of the tires at the tread, and you end up losing some contact patch.

With too narrow a tire, the sidewalls will bow outwards, and again depending on the sidewall stiffness this may cause the center of the tread area to lift, because the sidewalls pushing outwards will cause the tread to twist upwards.

I would imagine a drag tire with soft sidewalls would be less sensitive to this kind of size variation.

Glen, I'm sure the setup you've got works just fine, I'm just bringing up a general comment in case someone ever wants to play with sizes on street tires.

[Smokie]

stumpy I don't know much of anything about drag racing, but I'm good at observing data and comparing. Your 60' times are better than anyone on this forum and only Disney's hot rod Lincoln is a 60' equal to your car even though it reports a much higher rwhp than you. Since you are as far I am concerned King of the Hill to 60' I bow:bows: to your wisdom in matters of hooking-up and getting out of the box. I have a question: is it possible that the SS unquestioned superiority in the 1/8 mile is due to how the LT1 engine makes torque compare to the DOHC 4.6 32v? What do you believe is the greater factor, the tire/rim combo or the different ways the engine's produce torque?

[RCSignals]

Those of you with desk jobs and swivel chairs have surely tried to spin yourselves around while seated on the chair, and noted the difference in rotational speed as you extended your arms and legs and subsequently retracted them.

any pictures of this phenomenon?

Not everyone works at Government Office :lol:

[stumpy]

Hey Smokie, it's been fun getting there man. In fact it was more fun when I ran without a helmet. The helmet seems to diminish the head rush I used to get when I was only getting 2.00 60' times. You can run without a helmet above 13.99 at most tracks, except in NJ.

The reason the Impalas have great torque is that the stock LT1, a push rod engine, came with a very torquei cam. In fact, the general consensus among Impala experts is that the best cam for low end torque is the stock cam. It's very hard to beat for shreadding tires. That's probably the biggest factor in your comparison between motors. As I understand it, most OHV engines are slow to spin up compared to push rod engines, all that mass to move compared to a single cam and rocker.

In addition to having good low end torque, I make the most of it with a high stall TC. The dyno showed that I was making peak torque (314lbs) at 3,250 rpm, therefore I chose a 3200 RPM stall and it seems to be working better than expected.

To help plant the rear I have a HUGE rear sway bar, 1.5" solid bar that was designed for the 70's GTO. I also have 12 way adjustable racing shocks and I firm up the rear for racing. I also removed the front sway bar, actually disconnected it, and set the front shocks to '0'. This allows the front to spring up and helps transfer the weight to the rear to plant the tires. I always leave at full throttle and hook almost every time if the track prep is half descent.

[Smokie]

stumpy Thanks for info. :coolman:

[Logan]

Oie.... You guys are giving me a headache... :D

[FriendlySS]

Torque IS e.t. and HP is trap speed. For example. This weekend I ran a 13.47@100mph backed by a 13.49@100mph. I have seen the timeslips of the MM's and your trap speeds are approach 100mph at the 14.0 second barrier. In drag racing 60' is everything unless you uncork a bunch of HP after the 1/8 mile. In the SS and MM's corner is a huge weight issue which in turn leaves only one answer - you need torque! << if you you want a fast track car at least. I haven't been able to race Stumpy - yet! But there is a strong possibility it may happen this weekend IF the weather doesn't turn for the worst (which it appears). My SS dynoed 338 RWTQ before a full header and cat back exhaust. My best 60' to date is a 1.78. Yesterday I netted a 1.81, a couple 1.82's and a bunch of 1.83xx's with 275/40 17 BFG drag radials. I prefer to keep the tire diameter shorter than stock to boost the gear ratio. I was running 17PSI in the drag radials all day. I am sure a lighter rim with more sidewall would help. All the guys in our bolt on class that are in the top three run lighter wheels and 15" tires.
28" tall tires WILL slow you down if you compare them to a smaller (effecient) drag radial. This is only if you are concerned about drag racing.
I am sure the MM guys are pulling seats or bumper supports off yet to make their cars faSSTer like us crazy SS guys.

Are there any MM guys in the Raleigh area that want to take their cars to the track...............still waiting!

[stumpy]

Hey Eric, I cut a 1.699 this weekend. I was consistently in 1.71 territory. Now that I hear you're running 17" DRs I can vision running you down before the 1/8 mile. My car looks stock from the rear, but you'll know it's me anyway. :shot:

[RCSignals]

Originally posted by stumpy
My car looks stock from the rear, but you'll know it's me anyway. :shot:

:lol: subtle

[FriendlySS]

It's all at the tree my friend! Hopefully the weather holds out.

Just wait till these Southern SS's get a breath of that cold Yankee air!

[RCSignals]

FreindlySS

What mods have you done to get 250RWHP ?
Other results I've seen for stock '96 SS dynoed on a Dynojet were only 218.2 HP.

[b4z]

I guess we can take a step further and find out what the weight of the 18" stock rims with tires is and what the weight of the 15-16" wheels are with the ET tires.

[FriendlySS]

Originally posted by RCSignals
FreindlySS

What mods have you done to get 250RWHP ?
Other results I've seen for stock '96 SS dynoed on a Dynojet were only 218.2 HP.

The mods are in the sig, but when I dynoed the car. It had stock exhaust manifolds, cats, and exhaust pipes.

Hopefully I will have the car dynoed again soon. I just added new valve springs with CompCam 1:6 roller rockers.

[RCSignals]

So basically the extra HP is from the EEC tuning alone?

[FriendlySS]

That and making a free flowing air intake. K&N filter with a stock airbox with 1" holes drilled in it.

I am interested to see how much the headers, high flow cats, and cat back gained the car. I dropped about .4 tenths first time out with the new exahaust setup.

This past weekend with the new valvespring and roller rocker setup. I optimistically dropped almost a full .2 tenths.

I would estimate between 280-290 RWHP now, but also interested to see what happend to my torque numbers.