holley hp breaks up in boost
04-11-2015, 08:48 PM
#1
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
holley hp breaks up in boost Need a little help from Holley users. I bought my hp box a couple months ago. Got the car running- put miles on the new motor ran it without the supercharger and all was well. I put the belt on the supercharger now any time I get above 100kpa the engine breaks up so bad it shakes the car violently. It seems like the boost related issues i have seen reading the forums is at a certain boost level. My issue is a little different, if it gets any pressure at all the issue is there and only takes about 70% throttle, there is no way I can even make a WOT pass. There is something very wrong. the engine is a stock ls3 with 24x crank wheel and 1x front cam. I have ls2 coils, ngk tr6 plugs, stock plug wires, holley 160's E85 fuel. I am thinking coils need changed or I need a resistor plug. I would be glad to share logs and tune file. thanks!
04-11-2015, 11:55 PM
#6
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
afr's are 12.0 to 11.7 gas scale with 30-40% throttle. it misses so bad i cant really trust the afr at wot. it shows dead lean but cant expect that to be accurate. tried adding 20% fuel at a time until i had added 100% with no change. tried taking fuel out of it. have tried anywhere from 15 to 20 degrees of timing above 100 kpa.
not really related but on the ford motor it would run 20 degrees with the same plugs/gap on 11psi with e85
not really related but on the ford motor it would run 20 degrees with the same plugs/gap on 11psi with e85
Trending Topics
04-12-2015, 10:13 AM
#9
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
blown 06 i have not read your threads but i will. I drove the car for a couple of weeks with no supercharger belt. It runs great wot pulls to the rev limiter clean no problems.
It has always had a slight miss at an idle when it gets up to temp. I changed the wires from a set of taylors that i was given back to stock. This did not change anything. My buddy has a set of ls1 coils that I can borrow so i plan to try those tomorrow night. I know that the bigstuff ecu's will not fire anything but ls1's not sure if that is the case for the holley.
It has always had a slight miss at an idle when it gets up to temp. I changed the wires from a set of taylors that i was given back to stock. This did not change anything. My buddy has a set of ls1 coils that I can borrow so i plan to try those tomorrow night. I know that the bigstuff ecu's will not fire anything but ls1's not sure if that is the case for the holley.
04-12-2015, 01:48 PM
#10
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
just as a note. I slowed the blower down to see if a lower boost level would help. Same results it is not like it gets to 8 psi and has spark blowout. It will not make 1 psi without problem.
04-13-2015, 09:28 AM
#14
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
map sensor read fine to 160kpa i have a buddy with the exact same combo so may try swapping hardware with him.
if the reluctor runout was the culprit you would think that it would have a problem at rpm N/A as well (it does not)
we were talking a minute ago and are leaning more towards fuel problem with how violent the car shakes when this event happens. it feels like you are trying to drive through a rev limiter. In the log the engine rpm does not cut out or even look like there is a misfire. it will go to 6000 (only tried this once). the map kpa looks fine, fuel pressure rises with boost. timing is steady the injector duty cycle is less than 40% the one pid that i question is the fuel flow is over 400#/hr
if the reluctor runout was the culprit you would think that it would have a problem at rpm N/A as well (it does not)
we were talking a minute ago and are leaning more towards fuel problem with how violent the car shakes when this event happens. it feels like you are trying to drive through a rev limiter. In the log the engine rpm does not cut out or even look like there is a misfire. it will go to 6000 (only tried this once). the map kpa looks fine, fuel pressure rises with boost. timing is steady the injector duty cycle is less than 40% the one pid that i question is the fuel flow is over 400#/hr
04-15-2015, 03:47 PM
#17
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
quick update after changing coils and harnesses, map sensors, slowing the blower down, eliminating the fuel pump speed controller as a problem by running it full blast all the time, and everything else i could think i decided to take the blower belt back off and just drive it around, the tune has changed a bit (injector off times were incorrect on the old file). after all of this the engine is now doing this break up deal NA now. I am glad that it is so i dont have to worry about melting it down with boost while troubleshooting. a few people have pointed me towards my fuel map which i tuned until the holley was pulling the fuel out instead of adding with the compensation. still breaks up not as bad almost none in 1st lower rpm's in second and third yes but its real bad on the gear change (my converter drops 1k rpm on the shift.
04-15-2015, 05:39 PM
#19
Teching In
Thread Starter
Join Date: Dec 2014
Posts: 37
Likes: 0
Received 0 Likes
on
0 Posts
I did, I went from 40 base to 60 with the blower belt on the car. No change, I had to turn the pressure back down to drive home from my buddy's that was helping log/watch the wideband. Now that the issue is present while the blower belt is off i will try smaller increments. I am afraid that raising the pressure that much is going to cause some idle issues with the injectors being so over sized.