Low spool with Greddy..
 

Hi,

Is this spool @ 4k rpm right for td04h-15g or am I missing something ? I don't have the psi chart but it settles up to 0.6 bar soon after peaking to 0.8 bar. Actually I hate that low spooling and help would be nice :(


bone stock 1.6l -93
TD04H and Greddy manifold
Custom 2.5" dp
Custom 3" dp->back with magnaflow muffler , no cat
18x12x3" bar&plate china ic and custom 2" piping
305cc injectors
Fuelab afpr running 60psi base pressure (vac line disconnected)
Mspnp, no maf
turbosmart bleed valve, basic ball&spring -type

Here's my .msq and dyno chart. Running 0.6 bar (8.7psi)

(I have some problems with greddy manifold bolts to loosen up but it wouldn't mess this much, would it ?)

if it was leaking, yes, it would.

otherwise tighten the wastegate rod.

Do you have the stock studs in there? I'm running a combination of 3/8" studs, nord locks, and stover bolts, everything is good'n tight.

Wastegate is as tight as it could be...

But does that spool seems to be incorrect or normal for greddy ?

I'm running grade 8.8 studs with spring washers but I'm going to change them. Which ones are better:

Spoke bolts or grade 10.3 studs with nordlocks...

That seems good for a stock greddy, but you don't have a stock greddy anymore. It should be much better.

Safety wire is better than any locking washer or nut.

I though so. Any ideas what would help the spool and what's wrong with that setup. Other than wg and loose studs...

the spool looks typical for stock exhaust components.... something's not letting that turbine spin.


that's also damn good power for 9psi.....202rwhp.......

I didn't answer as fully in the last post as I wanted to since I was rushed to get out the door.

Alot of people go with the hardest grade of studs they can find. That's caused shearing issues for me in the past, I think it's because it doesn't have as much tolerance for expanding and contracting with the heat especially when tightened down too much. They also become a pain in the ass to remove if they shear because of the hardness. I prefer a larger diameter stud with a softer grade of metal.

Here's a test of nordlocks vs some other tightening methods.
YouTube - Nord-Lock Demonstration Video

"Stage 8" (brand name) header bolts are said to be really good and haven't heard anything bad about them. I haven't gone that direction because I know I'd lose the retaining clips frequently.

If you are know how to use safety wire you know it's a pain in the ass, but McMaster-Carr carries several sizes of predrilled bolts in american sizes. Often you can get predrilled bolts in metric sizes from motorcycle racing supply houses. If you want to cheat Aircraft spruce carries saftey wire washers that fit under the bolt head and has tabs that fold up to grab the nut, one of the tabs has a hole you can run the safety wire through.



Sorry, I don't have megatune loaded on this machine, what's your timing map look like?

Naturally, I figure I can set down and throw this together in minutes and an hour later, here I am. Anyways, I transposed my dyno at almost exactly the same PSI onto yours. Mine spikes to 11 psi and settles at 9, which is identical to your spike to .8 bar (11.6 psi) and settle to .6 bar (9 psi). The red #'s are conversions to hp and ft-lbs.
As you can see, though you seem to spool only a bit slower than me, your spool is not that lacking. Really, your graph looks like slower spool than it is because of the scale of the rpms. P.S. Nice dyno man.
-Ryan
http://i175.photobucket.com/albums/w...otranspose.jpg

look at the comparison to Rappadan's old GReddy setup....

http://boostedmiata.com/dyno_day_pic...s/rappadan.jpg


http://boostedmiata.com/dynos/greddy_compare.jpg


nothing special about his...3" turbo back, MS, around 12psi dropping to 10 or so.

Thanks for answering :)

I try Grade 10.9 studs and nord-lock washers and if they don't work, i'll move to the pain-in-the-ass safety wire system :makeout:

Grr, I don't like this low spooling even if this normal, like it look like it is :vash:

Maybe I should consider T2554 next ?

look at the timing rows where you start to spool, you're retarding heavily, even at 1-2psi....that will impede spool.


as apposed to a map like this:

http://boostedmiata.com/timing/alstiming.jpg

Hmm, interesting. I'll try a bit sooner ignition then... Damn I need to learn more ms related stuff

nicenicenice, manifold-turbo -connection leaked badly

we did new threads to the manifold and tightened 10.9 stud bolts, nord-locks and nuts.

The car pulls much better and wake up just after 3000rpm without raspy sound :) I'm happy!

I'll bring this topic up if the connection doesn't hold

I very well may have the same poor connection as you did. So you changed to studs instead of bolts? I've never heard of nord-locks, looked them up and they look like they should do the trick - my normal lock washers don't seem to be working well enough.
-Ryan

There should be factory fitted studs :vash: It's so much easier to fit the turbo.

I think that dp (at least mine) and maybe not-so-stiff motor mounts puts even more stress to manifold-turbo connection... who knows.

what length did you go with for the studs? I'm going to get grade 10.9 studs and nord-locks, but want to get the right length or else I won't be able to fit the nut onto the stud once the turbo is on.
-Ryan

for the record advancing timing doesnt always improve spoolup, sometimes slightly retarded timing will aid in spool on different engines.

Do you have a flexpipe on the DP? I would suggest one if not.

Chris