So obviously my car doesnt need a monster tire under it, but besides some et loss, is there a disadvantage to running a big tire, specifically 16” wheel selections, 3186 MT’s Big Bubba’s etc. I built the car to run big tires, but didnt give it a whole lot in the horsepower department. Anybody running big bubbas on a door car. Details, 2760 lbs, strut front, 4 link rear, 434 sbc, 5.29 out back and a 1.80 low in the glide. Currently has run 6.01 at 112 with 3186 MT under it. I’m of the opinion that even though I may give up et, I should be able to make it work fine consistency wise with big or small tires.

I can not say how much but it will slow it down.
Just like when you put skinny front tires on the car is faster not so much because of lighter weight but because of less rolling resistance.

Bigger rear tires would have more rolling resistance. But it may hook up good. When your feet stick to the track your tires are doing same thing.

quote:

Originally posted by Curly1:
I can not say how much but it will slow it down.
Just like when you put skinny front tires on the car is faster not so much because of lighter weight but because of less rolling resistance.

Bigger rear tires would have more rolling resistance. But it may hook up good. When your feet stick to the track your tires are doing same thing.

I’m specifically asking if there is a disadvantage besides the et loss. I know it will be slower, and that doesn’t bother me a bit, I can change the dial no problem lol. My number one goal is consistency.

I think that as the track changes for instance when sun goes down that it would effect the consistency and ET more than a smaller tire because of the increased rolling resistance.


It is a good question and I can not tell you for sure just give you my thoughts on it.

Once it's tuned, it'll repeat as good as any given set of dampers you put on it, repeat.

Kinda like a valve spring manages the velocity of the lifter and push rod.

quote:

Originally posted by Mike Rietow:
Once it's tuned, it'll repeat as good as any given set of dampers you put on it, repeat.

Kinda like a valve spring manages the velocity of the lifter and push rod.

Thats the process i’m working on. Only have a couple nights on it and i’ve made several changes trying to get it like I want it. I dont suppose it matters what tire is on it if I dont get the suspension at least close.

quote:

Originally posted by Stephen Hughes:

quote:

Originally posted by Mike Rietow:
Once it's tuned, it'll repeat as good as any given set of dampers you put on it, repeat.

Kinda like a valve spring manages the velocity of the lifter and push rod.

Thats the process i’m working on. Only have a couple nights on it and i’ve made several changes trying to get it like I want it. I dont suppose it matters what tire is on it if I dont get the suspension at least close.

Big tire small power, I'd run a lot of squat long low IC and the rebound clicker fairly tight. Transfer weight out of the gate.

What car do you have Stephen?

Here's the disadvantage.. My 6.10's Vega is light enough, and with fat tires on the back, that you have to "get after the throttle" pretty quick in the burnout or the big tires will try to push the fronts..

And I wouldn't have it any other way! Cold Track, Hot Track, New Track, Old Track, it'll hook.

quote:

Originally posted by TheBlueTruck:
What car do you have Stephen?

71 Demon that we’ve had forever. I just spent the last 3-1/2 years building a new chassis under it after it had been sitting the previous 11 years. You probably didnt see it but I brought it to the HRP divisional Saturday to get a chassis certification and had it out for a few hours while we tooled around on the golf cart. I’m not snart enough to post a pic here but you can find plenty on my Fakebook Page.

Link to Pic...I think

quote:

Originally posted by Yellow Ticket:
Here's the disadvantage.. My 6.10's Vega is light enough, and with fat tires on the back, that you have to "get after the throttle" pretty quick in the burnout or the big tires will try to push the fronts..

And I wouldn't have it any other way! Cold Track, Hot Track, New Track, Old Track, it'll hook.

I agree with that it should hook any where anytime and that is a good thing.

For bracket racers I think it is better to over tire a car than under tire but this is more than normal.

This might make it easier to discuss.

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by Stephen Hughes:

quote:

Originally posted by Mike Rietow:
Once it's tuned, it'll repeat as good as any given set of dampers you put on it, repeat.

Kinda like a valve spring manages the velocity of the lifter and push rod.

Thats the process i’m working on. Only have a couple nights on it and i’ve made several changes trying to get it like I want it. I dont suppose it matters what tire is on it if I dont get the suspension at least close.

Big tire small power, I'd run a lot of squat long low IC and the rebound clicker fairly tight. Transfer weight out of the gate.

Define long and low....i’ve been playing with the IC calculator a bit and I bet i’ve moved the bars 5 times now since the last time I ran it trying to make up my mind what I want to throw at it next.

quote:

Originally posted by Stephen Hughes:

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by Stephen Hughes:

quote:

Originally posted by Mike Rietow:
Once it's tuned, it'll repeat as good as any given set of dampers you put on it, repeat.

Kinda like a valve spring manages the velocity of the lifter and push rod.

Thats the process i’m working on. Only have a couple nights on it and i’ve made several changes trying to get it like I want it. I dont suppose it matters what tire is on it if I dont get the suspension at least close.

Big tire small power, I'd run a lot of squat long low IC and the rebound clicker fairly tight. Transfer weight out of the gate.

Define long and low....i’ve been playing with the IC calculator a bit and I bet i’ve moved the bars 5 times now since the last time I ran it trying to make up my mind what I want to throw at it next.

So, here's what we're talking, if you run the IC relatively long and low, when it comes of the brake it's gonna rock back and wind the tire. You wanna run the rebound on the damper tight, so you don't get a hop when the tire uncompresses or un-winds whichever you prefer to imagine it.

How long and low depends on how it looks leaving and / or weights / center of gravity.

Ultimately like anything, I think if you have a good set of shocks on it that'll repeat, it'll repeat timeslips.

What I mean by a shock repeating is, a lot of times a a lower end shock develops slack at high speeds. Back in the day I'd hear people say shocks don't matter I have big tires, that's wrong then and even more wrong in 2021. When you have a big tire like this ya really need a good shock.

Let your driveshaft graph lead you in coming up with a workable IC. If you have data. Something like this I'd want a check mark at the most, in the driveshaft gragh at the leave.

This message has been edited. Last edited by: Mike Rietow,

Yes I have data. It has afco double adjustable out back, strange double adjustable struts. Both are out of the box, no special valving. So you are saying tightening the extension will help overcome the hook, spin, hook issues that some cars have when the tire plants then unloads?

quote:

Originally posted by Stephen Hughes:
Yes I have data. It has afco double adjustable out back, strange double adjustable struts. Both are out of the box, no special valving. So you are saying tightening the extension will help overcome the hook, spin, hook issues that some cars have when the tire plants then unloads?

Yes Sir, if it's compressing the tire, then unloading on the hop when it unwinds / un-compress.

If you can get to where you could post images of the data, that would speed things up.

I think what you have for shocks will work fine. Just gotta find what IC it wants.

You definitely want it to rock back like the center illustration here shows, work the tire. Long low IC.

I have one of those big tire cars that repeats and is consistant. I am no good at advice and its a foot brake car, no button, 6.50 105 with around 1.40 60 ft. This car will hook in a mud hole.

Good looking car Stephen.

Is that the same car youe parents ran in the middle 70's?

quote:

Originally posted by TheBlueTruck:
Good looking car Stephen.

Thanks!!