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rx1 with new front mount acts like on the rev limiter at 7-8k

T
Jan 25, 2012
10
0
1
43
Iam pulling my hair out trying to get this thing to run right . This was a new build from scratch no matter what i do it will not rev past 7-8k at that point it sputters and pops out the exhaust like it is on the rev limiter .afr @ 12.2
What is on it .
Prologger with boost control
excel exhaust
garret gt-2864
Stacked head gaskets
new plugs gapped at 0.018"
billet Ts and Caps
Ts tied to u shape pilot tube
back side of carbs tied to dedicated 1/2" fittings with equal length lines
as Iam sitting here typing this iam thinking i still have 03 coils could these be arcing out when pressure rises ?
I guess i will go after coils if anyone else has any ideas they would be appreciated.
 
M
Jan 14, 2004
3,078
1,390
113
Are you confident that you have the boost sensor plumbing for the carbs done correctly? 7k is right where it comes onto the boost so it sounds to me like the carb may not be getting pressurized correctly. Is your fuel pressure set at 4-5lbs static at idle?


M5
 
T
Jan 25, 2012
10
0
1
43
fuel pressure at idle is set at 4.5 lbs on the malpassi reg .
I agree with what your saying it seems that the second the turbo spools and the boost spikes everything goes to hell.
Iam pretty confident that all of the plumbing is right but this is what I have..
The malpassi is plumbed to the bottom of the I/C
The back side of the carbs are plumbed with 1/2" lines that are equal length into two fittings in the top of the I/C centered between carbs 1/2 and 3/4
The billet Ts are plumbed from the pilot tube to a T with equal lenght lines to the billet Ts
........................
The pilot tube is not restricted right now . I think I read somewhere about restricting this signal with a 400 main jet . I have a couple of manual boost controllers around I guess i could try to restrict it a little
 
T
Jan 25, 2012
10
0
1
43
what do the o rings under the caps do ? What symptoms would someone that was missing ohh i don't know three of them have ? Decided to recheck the basics and found that . We installed the caps the night we had a Irish funeral for my buddies sled , guess we should have done that prior to whiskey lol . please tell me this might be the problem ................i am ordering a set tomorrow .
 
B

BigFish BC

Well-known member
Jan 27, 2005
3,348
1,139
113
kitimat b.c
o rings keep the carbs sealed when under boost,when carbs pressurise.you were more than likely were losing boost pressure out the caps causing the prob you had.
 
T
Oct 2, 2010
3
0
1
Finland
Did you sove the problem? I have a similar problem and I have not find a reason for this.
I have o rings in place (old ones)

Ps. I know that this is an old thread :)
 
T
Oct 2, 2010
3
0
1
Finland
I made billet t:s and i had litle leak (on a first field test and it worked somehow)
i added o-rigs so it will not leak anymore. I think that the problem started after that..
it worked somehow before so i am confused.
I have tried to pleed this line also. Fail. It will not work.


https://www.instagram.com/p/Bfoix8jFVcJ/

Here is a link before problem started. So it worked somehow before

Tomi
 
Last edited:

Givemeaboost

Well-known member
Lifetime Membership
Nov 26, 2007
991
157
43
Great Falls, MT
I don't know about other people but a guy with only two posts and no info of who he is and where he's from wants us to click on his link. It aint gonna happen.


Ken...........
 
T
Oct 2, 2010
3
0
1
Finland
I understand your concern?
I solve the rpm problem. It was a ignition problem , i use my lathe to modify my spark plugs so they will be tight to ignition coil.

But now it runs too rich afr is under 10 under boost and if i put the smaller main jet it goes richer .. i do not understand

Tomi
 
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