221LikesTeam CRC Xti 1/12th Scale!!
03-02-2021, 05:42 PM - Wikipost
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01-21-2014, 01:53 PM
#1306
The Xti lower pod plate is 46mm from center of football to center of rear axle. The alter ego lower plate is 50mm from center of football to center of rear axle. Alter ego main chassis is shorter than the xti chassis, not sure by how much though. I do know that by pairing the Alter ego chassis with the Xti rear pod setup it makes the suspension geometry nearly identical to what the XL was.
02-05-2014, 11:15 PM
#1307
Blind chicane
I have a tuning conundrum related to a specific layout that seems to crop up once a year at my home track. And I have a feeling it will be at the Nats.
We have a chicane at the far left side of the track. I usually stand on the far right of the drivers stand. Problem is, I typically run a relatively free and aggressive setup that requires constant corrections to the line.
With a chicane at the angle it is run, you can't really see the corner that well. It is almost blind, especially from where I stand. If my setup pushed a little, it would be relatively easy.
But as it is, I just can't consistently get through the section at a good clip because if the rear starts to come around too much - you can't really see it until you are into the boards.
What is the best way of calming a car in quick short directional changes without developing a push in the rest of the track?
We have a chicane at the far left side of the track. I usually stand on the far right of the drivers stand. Problem is, I typically run a relatively free and aggressive setup that requires constant corrections to the line.
With a chicane at the angle it is run, you can't really see the corner that well. It is almost blind, especially from where I stand. If my setup pushed a little, it would be relatively easy.
But as it is, I just can't consistently get through the section at a good clip because if the rear starts to come around too much - you can't really see it until you are into the boards.
What is the best way of calming a car in quick short directional changes without developing a push in the rest of the track?
02-06-2014, 05:53 AM
#1309
Last night I ran the XTI Transverse. Started with Chrome/Yellow. 55 front springs. Car was great at the start everywhere BUT the chicane. By the end, was too loose.
I went to Magenta fronts and it was much better at the end but still too quick in the chicanes. It wouldn't be a problem if I could see them better.
I wish I had thrown down my Xi for a run. It always feels more planted in these situations. Maybe I need to go Altered Ego on this setup!
My XI is DIALED on Magenta/Blue . But I feel that the XTI will be faster when the traction comes way up at the Nats.
So short of going to an Altered Ego setup, what is the best way of "calming" an XTI for lower traction carpet club racing?
Right now I'm 55 front springs with brace, laydown servo, 5 degree block with 2 shims forward, 1/2 degree camber, battery forward, blue side springs, 20k on front kingpin, 5k side lube, 0 toe, Magenta with 1/8 compound, Yellow rear with full compound and rounded sidewalls, transverse kit. Audi A8c .
Am I missing anything?
02-06-2014, 06:55 AM
#1311
Always seems like my HOT club setups are trash at bigger races!
02-06-2014, 08:52 AM
#1313
This weekend is our closest thing to a Nats warmup race. Will I see any of you here?
I'm hoping we get a big enough turnout to build some traction so I can learn a little bit more.
02-15-2014, 09:09 AM
#1314
Tech Master
iTrader: (40)
I had a little fun with 17.5 powered inline Xti this weekend at the Timezone GP. I put it P2 on the grid and was fortunate enough to grab the W. Randy was exceptional with his kit Xti at IIC, so I was easily inspired for this project. I wanted to make sure that I was using the latest springs (except fronts). This was a straight forward build with nothing funky done. The idea was to get a little more weight forward to reduce front tire slip in effort to see if I can reduce post run fade.... more so at club tracks then big events. I reversed the esc and battery location which makes the wires much shorter and efficient. I did have to use a piece of double back tape under the battery plate to keep it from sliding into the servo. On my car, I did have to sand the football a little to snuggle the esc a little closer. I wanted the shorter wheel base, so I chose the Altered Ego chassis which builds up at 197. I did use the Xti rear plate. I want to say the stock Xti chassis builds at 203. This car drove really well! I built it a week ago. I haven't raced stock since last spring but to my surprise I nailed the set up. Didn't lay a wrench to it all weekend! Now that's lazy racing. 
Here's how I put it together:
Front:
.50 front springs (old black)
Kingpin .402" with 50k that I heavily neglected
5* caster block with 2.0 riser
1* camber
1f/2b caster
3.25mm r/h
Middle:
Red center spring (new)
25wt shock oil
Tall ball stud on the upper plate
20k tubes
.50 sides springs, touching
3.5mm r/h
Rear:
-1.5 droop
3.5mm r/h
17.5 KS @ 57* time, 57/72
Tires:
CRC Black fronts; 40.8, CA full sidewall, full dope w/ SXT
CRC Yellow rears; 41.5, no glue, full dope w/ SXT
Body:
Black Art R8C
Brian
Here's how I put it together:
Front:
.50 front springs (old black)
Kingpin .402" with 50k that I heavily neglected
5* caster block with 2.0 riser
1* camber
1f/2b caster
3.25mm r/h
Middle:
Red center spring (new)
25wt shock oil
Tall ball stud on the upper plate
20k tubes
.50 sides springs, touching
3.5mm r/h
Rear:
-1.5 droop
3.5mm r/h
17.5 KS @ 57* time, 57/72
Tires:
CRC Black fronts; 40.8, CA full sidewall, full dope w/ SXT
CRC Yellow rears; 41.5, no glue, full dope w/ SXT
Body:
Black Art R8C
Brian
Very nicely done, Brian. Now a question. I notice you used an extended height ball stud on the upper plate to mount your shock. Would you have done just as well to use .45 front springs and left the shock mount in stock configuration?
02-15-2014, 12:21 PM
#1316
Tech Master
iTrader: (40)
Thanks for your reply, Brian. But I get back to one of my original questions. Focusing on the result and not the solution, wouldn't to car have done just as well using .45 front springs and left the shock mount in stock configuration? I look at that elevated ball and think that it would be overloading the front under certain conditions. That is why the .050 front spring. The lower shock angle would be less sensitive to small change and allow more opportunities for fine level tuning. I don't really know without trying it and want your thoughts when presented that choice.
02-15-2014, 10:48 PM
#1317
Going from 50 springs to 45's is going to have a bigger effect then a normal or tall ball stud on the shock. Going to a 45 spring is going to push more on corner entry. Lowing the back of the shock is going to make the shock feel softer too. Add both of those together and you will get less initial steering. So if that is the effect you are after, that should do it. Bottom line: try it! Don't take anyone's word on what something should do. Prove it to yourself.
02-16-2014, 07:58 AM
#1318
Tech Master
iTrader: (40)
Going from 50 springs to 45's is going to have a bigger effect then a normal or tall ball stud on the shock. Going to a 45 spring is going to push more on corner entry. Lowing the back of the shock is going to make the shock feel softer too. Add both of those together and you will get less initial steering. So if that is the effect you are after, that should do it. Bottom line: try it! Don't take anyone's word on what something should do. Prove it to yourself.
Thank for clarifying that, Brian. You said initially that you were looking for a setup that would be solid on "green" tracks. Green is my interpretation of your description. I have the same interest as I have been running almost identical setup to the kit instructions. I know that isn't going to work if I encounter a very strong groove of traction, so that is the interest. Now, you mentioned that the carpet was like fly paper on your shoes. My track never gets to that.
Right now with the .45 front springs and stock shock positioning, I experience acceptable turning on the first half of the corner and it is now steering better on corner exit. My track is bumpy enough that I need the softer center shock feel or my rear tires go off at 6 minutes.
Please don't take this as grilling or a challenge to what you are doing. I just am interested in how you think about coming to the solutions you did.
Last edited by davidl; 02-16-2014 at 08:00 AM. Reason: additions
02-16-2014, 09:46 AM
#1319
Yes, 45's will have less turn initiation with more mid and exit steering then say 55's. 55's will cut harder and carry more speed into a corner but then mid and exit should be less steering.
One pronounced difference with the inline car vs the transverse is side springs and dampening. The inline car likes softer sides and tube lube, such as .50's or blues and 10-15k. The transverse likes stiffer; .55 or whites and 20-30k. That is due the fact there is very little weight dispersed wide. The inline car shifts very little weight side to side.
Sometimes the inline car can be aggressive on turn entry and the best way I found to calm that down is to use the camber riser plates.
I do not think rears give up late in the run, its more of a fronts get too tacky. Although rears do give up if you see fuzz wrapped on them, but that is typically only pinks that do that. One trick that I have found that helps with tires holding on late in the run is more front sauce-less camber. But look at your fronts first. If the un-sauced part of tire is glazing up, try this: CA the front side wall nearly 100%, reduce to -1/2 camber, and sauce 90% of the front. I have a track here at home that is on a concrete slab that is roughly 60* and bumpy. I have to use this technique to get the car to last 8 minutes. Also, I use camber as a barometer for longevity. Use as much as you can to get steering but back off if oversteer shows late in the run.
Another notable about the inline vs transverse: the inline likes mid to open layouts and the transverse likes tight point-n-shoot to mid layouts. You can get them to both work well on all types, but if you want to split hairs....
One pronounced difference with the inline car vs the transverse is side springs and dampening. The inline car likes softer sides and tube lube, such as .50's or blues and 10-15k. The transverse likes stiffer; .55 or whites and 20-30k. That is due the fact there is very little weight dispersed wide. The inline car shifts very little weight side to side.
Sometimes the inline car can be aggressive on turn entry and the best way I found to calm that down is to use the camber riser plates.
I do not think rears give up late in the run, its more of a fronts get too tacky. Although rears do give up if you see fuzz wrapped on them, but that is typically only pinks that do that. One trick that I have found that helps with tires holding on late in the run is more front sauce-less camber. But look at your fronts first. If the un-sauced part of tire is glazing up, try this: CA the front side wall nearly 100%, reduce to -1/2 camber, and sauce 90% of the front. I have a track here at home that is on a concrete slab that is roughly 60* and bumpy. I have to use this technique to get the car to last 8 minutes. Also, I use camber as a barometer for longevity. Use as much as you can to get steering but back off if oversteer shows late in the run.
Another notable about the inline vs transverse: the inline likes mid to open layouts and the transverse likes tight point-n-shoot to mid layouts. You can get them to both work well on all types, but if you want to split hairs....
02-16-2014, 02:28 PM
#1320
Tech Master
iTrader: (40)
Yes, 45's will have less turn initiation with more mid and exit steering then say 55's. 55's will cut harder and carry more speed into a corner but then mid and exit should be less steering.
One pronounced difference with the inline car vs the transverse is side springs and dampening. The inline car likes softer sides and tube lube, such as .50's or blues and 10-15k. The transverse likes stiffer; .55 or whites and 20-30k. That is due the fact there is very little weight dispersed wide. The inline car shifts very little weight side to side.
Sometimes the inline car can be aggressive on turn entry and the best way I found to calm that down is to use the camber riser plates.
I do not think rears give up late in the run, its more of a fronts get too tacky. Although rears do give up if you see fuzz wrapped on them, but that is typically only pinks that do that. One trick that I have found that helps with tires holding on late in the run is more front sauce-less camber. But look at your fronts first. If the un-sauced part of tire is glazing up, try this: CA the front side wall nearly 100%, reduce to -1/2 camber, and sauce 90% of the front. I have a track here at home that is on a concrete slab that is roughly 60* and bumpy. I have to use this technique to get the car to last 8 minutes. Also, I use camber as a barometer for longevity. Use as much as you can to get steering but back off if oversteer shows late in the run.
Another notable about the inline vs transverse: the inline likes mid to open layouts and the transverse likes tight point-n-shoot to mid layouts. You can get them to both work well on all types, but if you want to split hairs....
One pronounced difference with the inline car vs the transverse is side springs and dampening. The inline car likes softer sides and tube lube, such as .50's or blues and 10-15k. The transverse likes stiffer; .55 or whites and 20-30k. That is due the fact there is very little weight dispersed wide. The inline car shifts very little weight side to side.
Sometimes the inline car can be aggressive on turn entry and the best way I found to calm that down is to use the camber riser plates.
I do not think rears give up late in the run, its more of a fronts get too tacky. Although rears do give up if you see fuzz wrapped on them, but that is typically only pinks that do that. One trick that I have found that helps with tires holding on late in the run is more front sauce-less camber. But look at your fronts first. If the un-sauced part of tire is glazing up, try this: CA the front side wall nearly 100%, reduce to -1/2 camber, and sauce 90% of the front. I have a track here at home that is on a concrete slab that is roughly 60* and bumpy. I have to use this technique to get the car to last 8 minutes. Also, I use camber as a barometer for longevity. Use as much as you can to get steering but back off if oversteer shows late in the run.
Another notable about the inline vs transverse: the inline likes mid to open layouts and the transverse likes tight point-n-shoot to mid layouts. You can get them to both work well on all types, but if you want to split hairs....
Thanks for your insight here, Brian. All of the things you have mentioned are things that I have experienced with these two versions of the cars. I just need to try elevating the rear of the shock for more steering into the corner. I like what I have but might like that more.
I will say that since I run the black or grey front tire, I have never experienced the front getting more aggressive. Just the rear giving up and it didn't have carpet fuzz on it. I like the black, grey and white/yellow, blue and green tires because they dont' pick up the fuzz.
I did spend some time using Magenta front and did experience problems with fuzz, increasing aggressiveness and glazing. The pink or magenta rear would have trouble with fuzz.
Most of these problems I mentioned come from running on carpet that has been sprayed prior to running. Spraying creates an unrealistic traction and inconsitant track conditions. Also, many times they run oval the day before we run on-road and the oval groove causes major problems with tires. The oval guys like to use purple based compounds that leave a lot of debrise on the running surface and the sprays have stuff in them that makes the purple compounds grease (bad word here) up the carpet. That is why shoes stick to the carpet. What happened to the "cotton ball test"?
