Low boost on large turbos
- Thread starter CopGn
- Start date
Intercooler
New Member
- Joined
- May 24, 2001
I don't get any. A lot of it is tune and if your motor can't flow it you can have issues. Surge is cool!
OneLethal87GN
R.I.P. Lethal GN
- Joined
- May 26, 2001
My new turbo is in that range and I plan to only run between 18 and 20 psi. I could only run 18 with my ole TE-60 and alky set on wide open with an old K-B hot flash chip. I do plan to get a chip for my exact set-up once I get all the parameters nailed down. I don't plan on much, if any, track time once my new engine is broken in either so 18-20 is probably the max my new turbo will see. No problem running 18 with the TE-60.
I can't run under 20 lbs, but that is as much a function of the wastegate as anything.....if you use the stock type wastegate, you need a HD actuator with a big turbo and min boost is around 20....lots of surge comes with the low boost program also...it isn't fun
if I did a lot of street driving, I'd get a TE-60 or smaller....there is zero advantage to a bigger turbo on a street driven car (all the other probs come up like converter, lag, traction, etc)
so give some thought to what you really want
if I did a lot of street driving, I'd get a TE-60 or smaller....there is zero advantage to a bigger turbo on a street driven car (all the other probs come up like converter, lag, traction, etc)
so give some thought to what you really want
sixgun86gn
six offender
- Joined
- Feb 10, 2002
I get no surge at all at16# with a te63.
twin 93 svt
Member
- Joined
- Jan 23, 2002
I keep mine at 17 lbs, and most cars not beeing trailored and hard blocked can't touch it! but you need slicks!
sixgun86gn
six offender
- Joined
- Feb 10, 2002
Yeah,what he said
.^
.^I am building a very fast street car or a 11.0 to 11.5 car. I have all the supporting mods as the ported heads and 9". I want to get as big a turbo I can handle on the street so that I don't have to buy another one later or have to run high boost. I am starting to think that maybe I would have better control over a smaller 63 turbo. Everyone is saying though that the new garrett 67 wheel is ultra effiecient and will spool as quick as the 63.
The other thing to consider is that with a big, efficient turbo, good heads, and a good frontmount intercooler you will probably be able to run 20-22 psi boost on 93 octane anyway once you get it tuned up, so I don't really see the big concern - but that's just me .
.Its mostly tune. I had an ext. chip and it ran well, but surged with my TE45A, but after putting my felpro in, the surge is gone. I have a 3200 stall, spoolup is pretty good, could be better. I run boost down to 15 psi right now, with a hd actuator. I relocated the act. bracket, and with just barely any tension on the rod, I get 15 psi. I turn it up at the track.
I used to have that prob.......
I had a 70 turbo w\ a garret .82 exhaust housing that I never could get over 24#. We tried everything, we even completly covered the wastegate opening and still could not make over 24#. Then we talked to John Craig. He knew exactly what I was talking about. I sent him my turbo and he sent me another 70 (GT) w/ a precision 63 xhaust housing. WOW. I put it on, backed the wastegate way off and went out and hit it. I had 30# RITE NOW. It used to take me a long time to build 10#, but now it will build 10# in a heartbeat. It spools like my Dad's hotair car.
I had a 70 turbo w\ a garret .82 exhaust housing that I never could get over 24#. We tried everything, we even completly covered the wastegate opening and still could not make over 24#. Then we talked to John Craig. He knew exactly what I was talking about. I sent him my turbo and he sent me another 70 (GT) w/ a precision 63 xhaust housing. WOW. I put it on, backed the wastegate way off and went out and hit it. I had 30# RITE NOW. It used to take me a long time to build 10#, but now it will build 10# in a heartbeat. It spools like my Dad's hotair car.
Originally posted by CopGn
How hard is it and what is needed to run low boost on a large turbo (63 to 70)? Is this possible without the turbo surging? In street trim I want to keep the boost under 20lb. I was told with a large turbo (67) that I would get a lot of surge. Is this true?
I went 11.09 @ 120.89mph last night on 20.5psi boost with my PT67 (26* timing). That was with an external wastegate and 3" downpipe with no cat back. I'm hoping to be able to run close to this on the street, with 20* timing.
Yeah, Thanks. I plan on running alot better. My changes are top gapless rings vice the second rings I had. Took out the DFI, thats where my 60 ft went. Put in a ME-R, and taking off the flowmasters. Also getting the car down level as soon as decide on rim size and b/s and putting on my H&R boxes control arms.
Sounds like a plan. I'm sure you'll hit 10s! I've been wanting to do my control arms also. Launching harder is what I need on my car bad. As you see below, I also have a 60' problem. Most of that is in the stall. Going to a TH400 soon, hoping the beginning of next season. Just sick on the 200R4 blowning.
Good luck,
Jason
Good luck,
Jason
I think it supposed to be when the turbo is blowing more air than the engine can ingest. I know I can get it on my car if I accellerate at about 3/4 throttle and leave it there. When the high airflow starts backing up due to the throttle plates being partially open, the car starts to buck.
