Saxo turbo help please

19th May 2012, 22:55

Fitted the turbo engine into my Saxo, got the print out when it was in the other car which reads 196bhp.. It's running sweet as a nut and everything seems to be working fine as I've been using it for a few weeks but it doesn't seem to be at it's full power, you can feel it boosting but not like it should, there is a dent in one of the boost pipes underneath from hitting the floor on a large speed bump but I'm not sure if that would be holding it back. Does anyone know what it could be? Cheers

19th May 2012, 23:00

no where near enough info..no info at all tbh!!!!

tell us:

what turbo
what boost
what engine
what compression
what management
what injector size and fuel pump
what type of kit

then we can.. guess

if you can give more it will help..

19th May 2012, 23:10

You know all about this engine anyway tho blackie! T2 turbo , blacktop vtr, not sure about injectors but got 5th and 6th, piggy back ecu, storm ecu for extra injectors, standard fuel pump

19th May 2012, 23:28

not being funny mate..but i read thread after thread of turbo conversions on here..same as most... 90% without pics or known specs..and they get to a point if any then stop...very few see it out till the end

i clicked onto yours today as seen an update..read the last 3 posts and clicked off..

im not a memory bank unfortunatley

and its not just so i can help..alot of the more knowledgeable ppl on here dont read progress threads..but they may be able to help you

not with that first post though

19th May 2012, 23:40

There isn't anyone else id prefer to ask tbh mate, I tried to mail you privately but didn't know how to do it.. I was askin in hope that you yourself would reply as you are the man for the job!

20th May 2012, 09:11

I think what blackie is saying is that it could be anything from the turbo through to a hole in your piston through to a blocked fuel filter a kinked and leaking boost pipe anything!!!!!!!!

Try looking through the air side of things first check all'!!!!!! Boost hoses are tight and not split then check fuel check the filter maybe change it

Then come back with some results

20th May 2012, 13:38

If I had o guess I'd say fueling, but as there's so little info in here or your progress thread then there's no possible way of telling

20th May 2012, 15:05

Dent in boost pipe won't change anything
unless its got a small leak

2nd and I'm gonna just add this in here 196hp on a dyno readout means nothing!!!!!
unless every single day of your driving life replicates exactly what was happening on the dyno.

another point, get rid of the 5th n 6th injector setup in my opinion they are bandaids for badly tuned motors running injectors that are TOO small for the job

i agree with blackie most likely fuelling

but.... if its a used motor that someone else has built id also do a compression test.

look for black smoke on boost ( sign of rings going )

heavy fuel smell when driving

check tail pipe for heavy carbon build up black

if there was any boost leak you'd have an up down idle and you'd know on boost cos you'd hear it

what are you using for boost control?

theres lots to look at

but one answer you gave was " its running sweet as a nut " and the butt dyno is always wrong

20th May 2012, 16:13

Thanks for the replys and answers, i don't really want to spend any more money on it as the thing is burning a massive whole in my pocket from using it daily.. I think I'm guna take it to a garage around here and let them have a look at it, set it up proply and give it a full service and put an uprated fuel pump on it.. Cheers guys

20th May 2012, 23:51

Found out what it was, took boost controller off and swapped with a pipe when putting the engine in and it was kincked on actuator.. Put the boost controller back on and wound it out a bit and it goes like a rocket now. Think I'm guna change fuel filter an put uprated fuel pump so looks like I'm guna keep it for a while

22nd May 2012, 16:43

do you have a boost gauge to show what boost you are now running?

11th July 2012, 12:22

Hi people sorry to re-open this thread but didn't want to start a new one.what injectors should I be running on my turbo jp4 engine I don't want huge power but it is forged so can handle it. Suggestions please

11th July 2012, 12:30

Depends what power you will be running mate, I run clio sport injectors which are good for about 200bhp at 3bar at the fly, but you can also run megane 225 injectors which are good for about 260 Bhp at 3 bar

17th July 2012, 13:06

put it on a dyno?

get the fueling checked, boost checked etc. if all checks out ok and its down on power, do an engine health check, compression, cylinder leakage etc. if you can access the ecu, see if its reading sensible values fromt he sensors, and the sensors cale correctly from min to max, particularly MAP or TPS sensors.

bad earths, air leaks and faulty sensors are culprit for most common problems on ALL cars.

colin.

17th July 2012, 20:38

Just read the 14 pages of your build thread and still a little confused as to what the actual spec is of your car CHEZNUT. Like blackie_2k5 said it would be good if you could tell us a hole lot more. Hover one thing that comes to mind was if there was any sort of boost controller / bleed screw used in the original setup its possible your running considerably less boost with out realizing. Another thing is how reputable was the person and you got it from and who was the rr from? You can easily make a rolling road show anything you like.

18th July 2012, 00:45

The engine isn't in the car yet but it's a forged jp4 engine gt25 turbo and run will be ran on omex. Been told Astra vxr injectors to look for bhp at 250+ bhp. yea I don't update my forum very much as don't use laptop very much

18th July 2012, 12:43

Quote:

Originally Posted by Rhysupply

The engine isn't in the car yet but it's a forged jp4 engine gt25 turbo and run will be ran on omex. Been told Astra vxr injectors to look for bhp at 250+ bhp. yea I don't update my forum very much as don't use laptop very much

There's a simple formula to work out your injector size which is this:

Injector Size = (Power (max Theoretical power you want to achieve) x BSFC)/(No. of Injectors x SDC)

Where:

Power: in HP
BSFC: Brake specific fuel consumption typically 0.6 for turbo's
SDC: Safe duty cycle around 0.8-0.85

As you said your running a GT25 which produces about 275hp max i think so your injector sizes you'll need will be:

51.56ib/hr or 541cc/min

Go on to Bosch or any injector manufacture and look up the flow rates at 3bar once you ago above 4bar you'll find the flow rate drops off tar dar there's your answer

Then all you gotta do next is work out the total fuel pressure you need to size your fuel pump which uses this simple formula:

Base fuel pressure + Total Boost + Pumping losses

I really don't get why people struggle to do this and instead buy crappy 5th and 6th injectors to compensate its not rocket science?

18th July 2012, 13:12

i think cheznut sold it i saw it on gumtree about a month ago for £1500