Losing Some Power Help?

[unix]

Hey, i had a shop source a low km's rb26 a few months ago put new turbos on everything else.. thing is we have it tuned with the power fc dejetro low boost at 1.2bar and hi boost at 1.38bar, it was making 400hp at the rear's on 1.38 when i first got the car back iv done 2,5000km's in it i took it bak to the shop was going to wind the boost up a little more to make 420hp and on the powerrun it only made 375hp the mechanic said my mufflers blocked caus it is stuffed all the craps being shot out on boost and stuff and it makes a bit of a noise but i took the muffler off and it isnt blocked at all.. so that isnt the problem, i recently only changed coilpacks to spitfire d1's i doubt that was the problem but so i just put the nissan ones back in.. you cant really feel the power loss but its there and i think its gonna get lower if anything and i wanted to get 420hp, does this sound like i could be losing compression?. Thanks to anyone that has any ideas and can help.

[R31Nismoid]

^ agreed.

very hard to tell with such very very limited information

[The Dan]

You will know if you do a compression test.

Have you checked your catalytic converter?

There are many many many things that could be draining your power. It's foolish to make a guess without coming forward with all the details of what has been tested and other possible symptoms

[unix]

Yeh mate, the cats been gutted so no problem there either, i just thought considering nothings been changed or replaced since it was run lasttime?

[tridentt150v]

could be fuel pump/filter/injectors/quality

could be a dirty air filter

could be a sensor

could be your ecu

after 2,5000km who knows and 375 to 400 isn't that big a difference, could be winter vs summer dyno, tyres, clutch, timing valve clearances and the list goes on

[unix]

It would be good if it was the air temp i couldnt remember if it was walm or not when it was dynoed the first time. its got a new intank bosch044 fuelpump new injectors new ecu no afm's...hehe i thought about everything i dont see what it could be i know it isnt much hp but i dont wanna have to add more boost to get it back to what it was making you know.. i want to get to 420hp

[The Dan]

It would be good if it was the air temp i couldnt remember if it was walm or not when it was dynoed the first time. its got a new intank bosch044 fuelpump new injectors new ecu no afm's...hehe i thought about everything i dont see what it could be i know it isnt much hp but i dont wanna have to add more boost to get it back to what it was making you know.. i want to get to 420hp

That fuel pump isn't in tank. And if you have the intank model then it is likely to be an 040 which won't see you all the way to 420hp anyway.

Also check for small boost leaks using an isolation pressure charge system

[unix]

Hey mate, Its an intank 044 i know for a fact.. there an external and internal model 044.. Ok ill have a look at all the lines for leaks have actually had a problem with a leak before seemed to make the car run like shit but seems to run fine i get knock pretty hi but its ment to have been tuned for around 20 on the fc controller on knock but it goes up to 30-35 so i thought thats slowly killing my engine and the pistons are starting to get f*ked and shagging the engine??.

I spent 25grand on this engine i know 30hp isnt much it just shouldnt be happening and i wanna find out whats doing it..

[The Dan]

Hey mate, Its an intank 044 i know for a fact.. there an external and internal model 044.. Ok ill have a look at all the lines for leaks have actually had a problem with a leak before seemed to make the car run like shit but seems to run fine i get knock pretty hi but its ment to have been tuned for around 20 on the fc controller on knock but it goes up to 30-35 so i thought thats slowly killing my engine and the pistons are starting to get f*ked and shagging the engine??.

I spent 25grand on this engine i know 30hp isnt much it just shouldnt be happening and i wanna find out whats doing it..

There is no in tank 044. There is an 040 which is an in tank pump but it flows much less. You can use the 044 and mount it in tank but it is not an in tank pump as such.

Knock of 35 is not bad. I would start to be concerned after 40 or so but anything around 35 will be fine.

25k on an engine? What the hell did they put in there? I can build a whole car with a 800hp engine including suspension and brakes for ~ $25k. That figure can't be right

[R31Nismoid]

25k... is that including the turbos, and every single part?

cause my forged build cost me 7k (excluding turbos etc etc), if you take all that into account, its 15k

[MBS206]

ZOMG! I lost 25HP between dyno runs!!!

Shit... Never seen that before... Oh wait... Yes I have... It's just the dyno not correcting it out perfectly. You haven't lost power, move on with it. Chasing dyno numbers is pointless. If you want your magical missing power back, when you do the run, make the air temp sensor on the dyno read higher then it really is...

[Strik3r]

25k... is that including the turbos, and every single part?

cause my forged build cost me 7k (excluding turbos etc etc), if you take all that into account, its 15k

"800hp engine including suspension and brakes"

I dont think your building an 800hp engine for 15k :>

[Strik3r]

on topic, what about your spark plugs ? Checked them out ? 25hp is a fairly small loss of power.. its possible the dyno is due for a calibration.. or like someone said, the air temp was ~5+ degrees higher.. aging/fouled plugs could also lose some hp.. lots of little things..

[Strik3r]

also to confirm it isn't your exhaust, do what ash normally sugests - drop the exhaust off at the end of the dump pipe.. will make sure its not a restriction in your cat/muffler.

[unix]

Wow got a few quick replys then lol, well all up after bein in and out the shop a year it was 24grand it was for everything turbos computer injectors rail reg power pc cams - gears springs, twinplate clutch, gearbox engine mounts just about everything except crackin the engine open,i will do that when i get enough money and want the car off the road again, If 35knock isnt that bad then i guess thats sweet pretty happy i thought that was bad.. im not after a jagic number on the dyno either if i wanted that i would of got a t78 or something i want atleast 400 caus my mech wont up the boost till i get that problem sorted out he thinks its my muffler and it isnt.. i thought it might be the coil packs thats why i was saying i changed them just after i got told it was 30hp less on the spitfire manual they show a dyno graph of gaining 30hp on a rb26 over the standard nissan ones.. the sparkplugs were changed when the engine was put it..fuel filter ect, i was told the 044 pump in it is in tank and i can hear it at the very bak of the car under the tank?, cheers

[R31Nismoid]

"800hp engine including suspension and brakes"

I dont think your building an 800hp engine for 15k :>

Who said i was?

I didnt, was the post above me actually, so maybe get your quoting right?

[Strik3r]

oh you were referring to OP not dan.. I thought you were claiming dan's figure of $25k was too high for an 800hp car...

spitfires are a slight improvement over standard coils.. if your standard coils are old and breaking down under load, then splitfires will make a big difference.. but in any circumstance, they shouldnt lose you HP..

In the end, like we've suggested, its likely to be something else (dyno calibration, air temp) rather than your actual car... If your tuner is convinced its the cat, drop the exhaust off on the dyno and see if that makes a massive difference.

[R31Nismoid]

nah i was talking about 25k for that dude to make his setup... seems a bit high as he also said he had to source a low km RB26 (which brings other questions)

25k... with a low km RB26... was that a stocker or a build 26 with low kms?

[unix]

The 25k was including the motor i think i payed about 6grand for that its just got standard internals i was told it should last a while enough for me to be saving to do a rebuild but i dont see that happening for a while the engines holding up fine so far no noises or anything i just wanted to up the boost a tad more then leave it..