HX35 to big for my WBX 1.9L?

[streetvwnorth]

Hi!

I'm posting this topic because i need help to figure why i don't make more then 0,9bar on my 1.9L WBX engine regardless rpm. I know there are some guys out here running turbo charge WBX engines and maybe you can bring new light to this problem.

Engine facts:
Stock WBX 1.9L DG (fully restored with weighed pistons, etc)
Stock intake
Stock typ1 camshaft and hydraulic lifters
Holset Hx35 twin scroll turbo housings with internal Wastergate
685cc fuel injectors, Runs on E85
Megasquirt with Edis
Homemade 38mm exhaust with twin scroll
64mm down pipe (exhaust back pressure before turbo housing follows the boost pressure)



The engine starts to load app. somewhere between 2500-2800 rpm and the boost increases with the rpm in a linear way. And when i get to 5500-6000 rpm i have 0,9 bar of boost. I have pressure tested my intake and sealed every leak. I try to disconcerted wastergate but no difference in boost pressure.

I´m planing to rebuild the engine this winter and do some modification such as install bushings so i can use typ-1 lifters, bolt on a 1.25 rockers and put on a intercooler.

/M

[fastback]

how's your timing?

[DORIGTT]

Waiting to see the outcome of this setup.

[streetvwnorth]

Here is my timing.



/M

[fastback]

If asume your timing is "dialed in" , so 24 degrees is actualy 24 degrees?
if so , you could add a lot more timing here
at 100kpa you could easy have 33-35 degrees with retard down to 26'ish at 200kpa
you should also have lowest timing where the max torque is.
above 4500-5000 you can add a few degrees
not oppsite as you have it

and at lighter load and cruise (below 100kpa) you can add more timing from the base 33-35

[streetvwnorth]

This is what i tested.



My opinion is that the Turbo kick disappeared. It usually kicks in around 3400-4000rpm, but not now. With this timing the acceleration was more like a normally aspirated engine. But i got 1,1 bar boost at 6000 rpm. This was with the wastergate disconnected.

/M

[fastback]

do you log?
maybe post your logfile.

[streetvwnorth]

And here are two loggfiles.

Just pure acceleration all gears.
http://streetvw.se/filer/acc.xls


And cruise with acceleration.
http://streetvw.se/filer/cruise.xls


/M

[riseabove]

Now i know where i recognized you M.... portingguides for VW heads and homemade flowbenches and so on

NICE that you finally jumped the wagon on the beautiful WBX design !

Vi är fler svenskar o nordbor på det här forumet. riktigt bra ställe för övrigt.... alltid kan man få några bra svar.

[streetvwnorth]

Well, it was some years ago now. But that project, along with my homemade dyno, gave me very good basis for tuning engines. Of the record, at one time i even slept with an cylinderhead beside my bed. Just in case i had to check something during the night. Så vad har du för funderingar kring mitt problem med laddtrycket. Några tankar?

/M

[streetvwnorth]

The engine i going apart now for a upgrade. I´ll come back next summer with an update! You can follow the progress on my homepage www.streetvw.se

/M

[streetvwnorth]

For my upgrade of the motor i´m planing to put bigger exhaust valves on my WBX heads. Does any one know where i can find bigger valves, lets say 37mm, with the right length (122,7mm) or some other ideas how i can do this.

/M

[riseabove]

i think most engine repairshops should be able to get you manley stainless valves in the correct lenghts and size

ellemann-jakobsen racer trimning in partille didnt have any problems sorting me out even though they are primarily volvo tuners.

im also in the planning process of building up my turbo heads for my 2.1 dj engine, porting , and 3-angle valveseats will be enough for next season i think.

[volksbugly]

HX 35 is a huge turbo, you should look at getting an hx-30

This is an hx30 next to a hx35

[riseabove]

friends of mine have been running hx35s on 1.8 liter nissans and 2 liter toyotas very successfully, its really not to hard to get a hx35 to spool..... myself im propably going with a schwitzer turbo of a racecar.