Boost control issues

I'd remove the 66 and put on something with a smaller turbine and compressor. It will spool faster and be easier to control because the mass ow potential is closer to your goals. A 66 compressor will support at least 650-700hp ( or more on some engines)depending on how it is built. It's not happy trying to support 380hp.
 
Okay guys I got the boost down to 19 to round 20 pounds um I'm thinking this is going to be okay but the wastegate is all the way out is the any way to improve the lag I have art car 9inch non lock

Posted from the TurboBuick.Com mobile app
 
Ported out to 1.25

Posted from the TurboBuick.Com mobile app
 

Attachments

  • 1391918877013.jpg
    1391918877013.jpg
    71.1 KB · Views: 160
Engine build is gn1 heads, roller rocker 1.65, 220/224 cam, 9 inch art Carr non lock, 4 inch maf, alky injection, precision stretch intercooler. If I tighten up the wastegate rod a little will I get less lag. Rod is all the way out.

Posted from the TurboBuick.Com mobile app
 
Did you contour or radius (smooth ) the sharp inside edges of the waste gate opening?
This would be the most important thing to do! Hope you didn't open up the hole too much………..it looks a little "oval", really should be round.
Better check how it seals before you bolt the turbo back on the car.
With the exhaust housing still separated from the rest of your turbo, It would be best to bolt on the down pipe to your exhaust housing now that you've opened up the waste gate hole & mark the puck with lipstick, grease, white out….whatever & open and close the puck several times so that you will see a witness mark as to it's relation to the opening. It should have at least 1/8" sealing area over the hole in order for the puck to seal properly.
 
I did smooth the inside of the wastegate out. If it didn't seal correctly or was to big, it would still over boost correct? Boost stays around 19# when I tested it yesterday with it put back together. Someone else told me it would be oval and not fully round due to the exhaust turbine wheel.

Posted from the TurboBuick.Com mobile app
 
In the picture, I went to the inner edge of the marker of the line I marked to ensure I wouldn't make the hole to big.

Posted from the TurboBuick.Com mobile app
 
I did smooth the inside of the wastegate out. If it didn't seal correctly or was to big, it would still over boost correct? Boost stays around 19# when I tested it yesterday with it put back together. Someone else told me it would be oval and not fully round due to the exhaust turbine wheel.

Posted from the TurboBuick.Com mobile app


"Someone else told me it would be oval and not fully round due to the exhaust turbine wheel".


Dunno about that. I had mine opened up on a bridgeport milling machine to ensure the opened up hole was round & to make sure it was centred in the pucks footprint. Then carefully radiused the inside edges of the opening.

If you make the hole too large, your puck won't be sealing fully & then you will have the opposite problem…i.e. will have problems building boost. That's why many have been cautioning you not to open up the hole too much.
 
Oh ok, well I was at 20 lbs yesterday with rod all the way out and not tight at all. I'm going to tighten up the rod a little today to see if I can get rid of some bottom end lag

Posted from the TurboBuick.Com mobile app
 
I had a turbo like this. You need to port it more if you want to lower the boost. You could sell your THDP and go with an RJC unit with the larger puck. THDP's sell quick.
 
Well I went and tighten up the rod a little and I'm maintaining #21 lbs of boost. I think I'm pretty comfortable with this for now. This will be my street tune and probably will stay there to be safe. This new setup of mine is really hard to learn and figure out. Going from a Te-44 turbo to a T66 turbo is night and day. I do love how it keeps pulling on the top end , but I really miss the quick response the te-44 gave me. Maybe I need a ball bearing turbo but may have till next Christmas for this. Thank you for everyone's help and input !!

Posted from the TurboBuick.Com mobile app
 
On unopened engines, when my buddy had a T44 and I had a T64e (T66), he'd pulled on me with 15 PSI vs my 18 PSI. Once I dialed it over 20 PSI, the 66 started to shine. Try it over 25 PSI. It's addictive. I made over 500 rwhp on stock heads and stock cam with this turbo.
 
On a WOT run how does your boost vary from 2nd, 3rd, and 4th gear? I'm asking because I'm having a boost issue where boost if much different in each gear.
 
Top