I have been looking and not finding much on the 73htz. I am trying to find out what everyone else is full spool at. Been getting the car street tuned after doing a bunch of stuff and I am not getting full spool until about 4500rpm

Built and pocket ported head by headgames motorworks, Ferrea 6000 series valves, Ferrea valve seals, Map behive valve springs and titanium retainers, kelford 272 cams, kiggly hla, ARP Head Studs, FP cast manifold, FP Green 73HTZ 84mm Surge port, TiAL MV-S 14.5 psi spring, grimmspeed ebc, Stm fp downpipe with open dump tube, Megan resonated test pipe, M2 catback, ETS short route intercooler piping with ETS 3.5in intercooler, Tial Q bov, FIC 1100cc High-Z Fuel Injectors, walbro 255, Spoolin Up COP, Omni 4 bar map sensor, Ets 3in sd intake, Extreme PSI Heat Barrier Intake Manifold Gasket

 

SS housing or MHI housing?

 

By full spool do you mean peak boost? What's yours set at?

 

Ss housing
Building boost like this
3500rpm 5lbs
4000rpn 12.5lbs
4500rpm 27lbs

 

That seems a bit slow but it is the SS housing so I know that it gives up some spool for better top end. On my 73HTA in an MHI housing, I see ~28psi at 4k rpms and this is on a stock block limiting the spool to keep the stock rods happy.

I just finished building the bottom end so I'll find out what it is really capable of in the coming weeks.

 

What gear?

 

3rd

 

Seems to be about right for the SS housing. They're kind of lazy, especially on a 2.0L.

 

Is it really that bad? That sucks.

 

Probably 3rd

 

Its crazy to me to think that they moved to the SS housings. I know that the supply of good MHI hotsides was the limiting factor but an SS green is basically a TS red at this point.

 

Twin scroll is your friend.

It seems that the SS housings bump the turbo a color up.

SS Green will spool like an MHI Red. SS Red will spool like an MHI Black. Etc.

 

I figured, I just didn't expect it to be THAT bad. That housing hurts.

 

I have the OG JB Black and I'm full stupid by that RPM. I was actually debating about moving down to a Green but if I can't get a twin scroll it'll be pointless.

 

If it is normal then I am fine. I did want a little faster spool but if it makes power I am fine. Will need to see how if feels getting off and back on the gas in the turns. Going to double check and makes sure there are no exhaust leaks and do another boost test.

This is what the graph looks like now. Still needs some more time tuning