Slow 6152 spool up


Well-Known Member
I have a 6152 turbo that spools up really slow. I had some leaks in the driver side header, and the crossover pipe, but they are now repaired. I'm also running a PTC non lu converter, which made a little bit of difference from my old converter, bit not too much. It has a Precision exhaust housing on it. Would it make a big difference if I switched to a Garrett housing?
What size PTC? What are the numbers on it? Most 10" and 9.5 properly spec converters would spool that 6152 no problem.
9.5". Stock heads on a TTA with stock headers. 3" down pipe and exhaust. Stock maf with no screens. Intake is ported, and 62mm throttle body. Car was running lean during spool up like 15.0 on the WB, so I turned up the fuel pressure a couple psi. The spool up, and af ratio did get better, but it still spools pretty slow. The Turbo I used to have was a ta49 with a Garrett housing. That turbo spooled super fast.
Stuck puck,puck not covering hole,too rich, or you could still have exhaust leaks. Did you port the wasregate hole?
Wastgate hole is ported. I have the oversize puck from Rjc. It has about an 1/8" seal all the way around, and the puck moves easily. I use a Greddy bspecII boost controller. I did turn it all the way up, and didn't get boost over 23 psi though. As soon as I get my rear end back together I'm going to see if it will boost higher with a manual boost controller.
I thought when I originally found my header leaks that I found the problem, but after I fixed them the spool up wasn't any better.
6152 is the wrong turbo for a stock headed engine unless you plan on running boost in the high 20's all the time. Its kind of a mismatch of wheels too. The gt35 compressor will run out way before rye t350 turbine.The ramp in tune is hurting it. A stage 3 turbine with a Garrett .63 ex housing is nice. It covers up a lot of ramp in issues because it needs much less ex energy to spool.
So can I change the turbine on this turbo, or should I be looking for a different turbo altogether? Sorry I don't know enough about turbos to fully understand your explanation. I do plan on running in the high 20's for boost. I'm slowly tuning my way up there. At 23 pounds it's looking pretty clean so far. I'm running 100 octane, and it's my first season with alky
I'd be looking for a different turbo unless you are planning on running faster than 122mph in the quarter. It's not cost effective to switch turbines
I'm looking for as fast as possible. I have a friend here that's helping me as I'm learning to tune. I hit almost 119 in the quarter last year, but it was with c16, and it wasn't a clean run. It was also with a Precision single disc lu. Turned it down, and I'm working my way back up slowly. People keep suggesting a 6262, but I don't want to get another turbo that spools slow.
Then you need to change turbos and or converter and get the ramp in fuel right. The 6262 is great but I wouldn't run one unless is was looking to get at least 123mph out of it. If not you will need a lot of wastegate unless you have a restrictive exhaust. The 5862 would probably suit you better. I've got a 5857 with Garrett .63 in the parts for sale. It will make more power than a te44 and will spool just about as fast.
I think the converter I have should be good. It stalls well over 3000. I'm definitely looking to trap over 123. I need to find out why I can't get it to boost higher. I'm currently waiting on parts for my rear end, and I'll be able to drive it again. By a lot of wastegate do you mean keep the spring tension high? Thanks