RB Concept Engine Thread
#258
if you want more bottom end use the RB 2604 pipe with a long header that should help
#259
yes it does come with ceramic bearings and best pipe is once again RB 2604 pipe with either medium or short header depending on what you want more top speed go with short best all around go with medium
#260
Hey guys I need some help ................I have a C6BB7T ...broken in .........finally tuned up and running well .
I have a issue though that I can't figure out . It "hangs" a idle at the end of a straight away .
I have lowered the idle
I have gone richer and leaner on the HSN and the LSN ...........
If I go richer on topend it goes away somewhat but the all around performance is horrible . Going leaner makes it worse of course .
Going leaner on the bottom end makes it WAY worse so I go as rich as I can on the bottom without hurting all around performance .
As I go even richer in the bottom end it "hangs" a idle for LESS time but it drowns the motor right out and won't even take off after 5 seconds .
Is this just a characteristic of these motors ? Is it because it's a turbo head ? I have heard that standard plug motors do less of this . Is my pressure line to short or too long ? I have checked for leaks and covered all the bases I think . Any help would be appreciated . Thanks Dave ........
I have a issue though that I can't figure out . It "hangs" a idle at the end of a straight away .
I have lowered the idle
I have gone richer and leaner on the HSN and the LSN ...........
If I go richer on topend it goes away somewhat but the all around performance is horrible . Going leaner makes it worse of course .
Going leaner on the bottom end makes it WAY worse so I go as rich as I can on the bottom without hurting all around performance .
As I go even richer in the bottom end it "hangs" a idle for LESS time but it drowns the motor right out and won't even take off after 5 seconds .
Is this just a characteristic of these motors ? Is it because it's a turbo head ? I have heard that standard plug motors do less of this . Is my pressure line to short or too long ? I have checked for leaks and covered all the bases I think . Any help would be appreciated . Thanks Dave ........
#261
It sounds like the balance between the LSN and the idle screw is out of whack. This problem is often caused by a too high idle setting being disguised by a too rich LSN. Takes a little tinkering to get it fixed but it's not hard once you have experienced it a time or two and figured out what to do.
Normally just richening the LSN will cure the problem but if it doesn't you may need to try something else. So here is what you do, run it and get it up to temp. Get the HSN set right and get it nice and hot. Come in and let it sit at idle. If the idle stays high for a long time just back off on the idle screw until the idle comes down and you should be set, or at least really close. If the idle is really fast for just a few seconds and then goes right down to a reasonable level then try leaning the LSN.
BUT HERE IS THE TRICK.
Leaning it sounds backward since it is going to make the problem worse but that is the idea. Lean the LSN a bit, go run a good hard lap and come in again. Keep doing this until the idle stays really high for a while (maybe 10 seconds or more) and then reduce the idle screw until you get a low, steady idle.
Normally just richening the LSN will cure the problem but if it doesn't you may need to try something else. So here is what you do, run it and get it up to temp. Get the HSN set right and get it nice and hot. Come in and let it sit at idle. If the idle stays high for a long time just back off on the idle screw until the idle comes down and you should be set, or at least really close. If the idle is really fast for just a few seconds and then goes right down to a reasonable level then try leaning the LSN.
BUT HERE IS THE TRICK.
Leaning it sounds backward since it is going to make the problem worse but that is the idea. Lean the LSN a bit, go run a good hard lap and come in again. Keep doing this until the idle stays really high for a while (maybe 10 seconds or more) and then reduce the idle screw until you get a low, steady idle.
#264
#267
Tech Addict
iTrader: (7)
Joined: Sep 2007
Posts: 536
From: Canberra, where the best clay is
hey alll
just a cupple of questions about the Xenon ALPHA.
i have just done 2 tanks on a runin bench but after reading some of the earlya posts iam thinking to just stick it in the car from now, but i have a bit off ecperiance with the bench having run in a fair few RB C6 s on it.
also after the run in proses will i have to pre heat up to temp befor each run or will it be fine.
and just tune it the dsame way as i do with my C6 off road or will i need to have it sounding richer or so.
thanks heaps for your help
anything else i need to know just tell me lol
just a cupple of questions about the Xenon ALPHA.
i have just done 2 tanks on a runin bench but after reading some of the earlya posts iam thinking to just stick it in the car from now, but i have a bit off ecperiance with the bench having run in a fair few RB C6 s on it.
also after the run in proses will i have to pre heat up to temp befor each run or will it be fine.
and just tune it the dsame way as i do with my C6 off road or will i need to have it sounding richer or so.
thanks heaps for your help
anything else i need to know just tell me lol
#268
hey alll
just a cupple of questions about the Xenon ALPHA.
i have just done 2 tanks on a runin bench but after reading some of the earlya posts iam thinking to just stick it in the car from now, but i have a bit off ecperiance with the bench having run in a fair few RB C6 s on it.
also after the run in proses will i have to pre heat up to temp befor each run or will it be fine.
and just tune it the dsame way as i do with my C6 off road or will i need to have it sounding richer or so.
thanks heaps for your help
anything else i need to know just tell me lol
just a cupple of questions about the Xenon ALPHA.
i have just done 2 tanks on a runin bench but after reading some of the earlya posts iam thinking to just stick it in the car from now, but i have a bit off ecperiance with the bench having run in a fair few RB C6 s on it.
also after the run in proses will i have to pre heat up to temp befor each run or will it be fine.
and just tune it the dsame way as i do with my C6 off road or will i need to have it sounding richer or so.
thanks heaps for your help
anything else i need to know just tell me lol
.This week has been my first experience with the Xenon Alpha and it has taken a little getting used to. I would pre-heat it for the first several tanks. Maybe even the first half gallon or so. Tuning is a bit different as well. The new carb is great and holds a tune well but the motor seems to like a rich setting at first. I found that the motor needed to be rich enough to not even shift for the first few laps. It will clear up after a minute or so of running. Keep the low end nice and rich or it might get sluggish during the heat. Get it right and it's a missile.
For 30% (and maybe even 25%) add a .1mm head shim. I had a bit of a detonation problem but adding another shim did the trick and runs great.
2013 pipe is the ticket.
Did I mention I love the carb?
#269
Tech Addict
iTrader: (7)
Joined: Sep 2007
Posts: 536
From: Canberra, where the best clay is
thanks hepas for the reply
i love the carb to it looks great.
only had 2 tanks through it now on the runin bench but cant wait to get it in the car.yer got the 2013 pipe for it. iam runny 25% mecca off road wich is apparently a re labled RB concept blend so i think its 11% oil or so.
i love the carb to it looks great.
only had 2 tanks through it now on the runin bench but cant wait to get it in the car.yer got the 2013 pipe for it. iam runny 25% mecca off road wich is apparently a re labled RB concept blend so i think its 11% oil or so.



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