PT7675 Vs. Turbonetics 7875?
PT7675 Vs. Turbonetics 7875? I ordered a precision 7675 from Huron speed a few weeks back, and it turns out its gonna be back ordered at least 3 weeks, and they offered me to change my order to a 7875 turbonetics. The 7675 is cast wheel and journal bearings, whereas the 7875 has ball bearings standard and also a cast wheel. The 7675 I ordered in .81 ar, but the 7875 is only made as small as .96ar.
Originally I planned on keeping the car M6 but now it's going to have a A4 trans, so spool time isnt going to be as vital for the car to be fun to drive now. That being said, its winter here and the car wont be driven for probably 3-4 months when the weather is better, so the wait time isnt really a concern. The goal for the car is about 700-800whp max with a SBE 5.3 with Gen4 rods/pistons.
Would the turbonetics be as good as the precision? I've heard that the precision is a much better engineered unit from some people and the turbonetics is relatively new so not terribly proven. Would one spool much faster or make much more power than the other? Is one likely to be of better quality? Price is pretty much the same either way, I just want the best between the two. If I do stick with the precision, should I go for a .96 ar instead of .81 now?
Originally I planned on keeping the car M6 but now it's going to have a A4 trans, so spool time isnt going to be as vital for the car to be fun to drive now. That being said, its winter here and the car wont be driven for probably 3-4 months when the weather is better, so the wait time isnt really a concern. The goal for the car is about 700-800whp max with a SBE 5.3 with Gen4 rods/pistons.
Would the turbonetics be as good as the precision? I've heard that the precision is a much better engineered unit from some people and the turbonetics is relatively new so not terribly proven. Would one spool much faster or make much more power than the other? Is one likely to be of better quality? Price is pretty much the same either way, I just want the best between the two. If I do stick with the precision, should I go for a .96 ar instead of .81 now?
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I have the tc7875 with a 1.15 a/r. My hot side is a single 3 inch pipe going to the turbo and with a 6 speed and stock ls1 as soon as I went WOT the motor went into positive pressure. Don't think spool time will be a issue. The turbine wheel is so small it spools with ease no matter what size a/r you get.
Either turbo will meet your goal. The .96 would be better IMO to carry the power out longer then the .81. Im stuck between an precision 7675 and the turbonetics as well. There doesnt seem to be a lot of info on the new turbonetics yet but I wouldnt let that sway me.
I would go with a .96 a/r on either turbo. Mine makes full boost around 3400 through a full exhaust and a stock ls1 cam. I had a 4l80 with a Yank stall in the car this summer with this turbo as well and it was a ton of fun. I just preferred the manual for a street car.
So from a quality standpoint is there really any difference? I'd hate for either one of those $1k+ turbos to take a **** on me. Anyone care to elaborate on the Precision turbo failures?
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I went with the turbonetics because it was cheaper by a few hundred at the time and no failures that I can even find.
There was a vendor on here and I can't remember who they were but they said turbonetics had one of the best reliability reps of all the turbo manufacturers. Their failure rate was the lowest.
As for precision....from the storys I've read on here they tell one guy his -3 oil feed line was too small and the next guy with the same issue, same turbo that his -4 was too large and he needs to switch to a -3 feed with a restrictor.
They change the setup and the exact ssme thing happens with the rebuilt turbo.
There was a vendor on here and I can't remember who they were but they said turbonetics had one of the best reliability reps of all the turbo manufacturers. Their failure rate was the lowest.
As for precision....from the storys I've read on here they tell one guy his -3 oil feed line was too small and the next guy with the same issue, same turbo that his -4 was too large and he needs to switch to a -3 feed with a restrictor.
They change the setup and the exact ssme thing happens with the rebuilt turbo.
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i ran a smaller turbonetics unit before switching a larger precision. Both are great. Any turbo will fail with poor oil quality/supply. Precision turbos have always put up good numbers from what i have seen. I think youll be happy with either to be honest.
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I recall reading a thread on here where someone sent their turbo off to anotherdumre builder after precision rebuilt it twice already only to fail and say it was starved of oil. The new re builder solved the issue and as far as I know the turbo was fine after that.
I know that swayed me enough to get another brand turbo.
Reading up on the reliability and warranty hassles I decided to do the Turbonetics 7875 instead. For me it's not really a big deal to lose a marginal amount of power in tradeoff for potential failures and huge hassles when dealing with their warranty. From what I've searched and read the pt7675's are more reliable than their others but that not something I'm going to chance. I saw Wicked69's thread with his pt6262's that failed and ended up having better luck with on3's and the run around he got in terms of service. The ball bearing's will probably make up for any difference in spool or power for me.
My Turbonetics 7875 1.15 ar ran a best ET of 9.92 @ 140 on 15 lbs. Best MPH came on 16 lbs. and was 142. Didn't get a chance to see what it would have done running it any higher the day I was at the track.
I went with the pt7675 for my car. M6 3.42 gear.
I can tell you this traction is a big issue without decent tires behind it lol. It has no lag and carrys the power threw the upper rpm's very well. I wouldn't go any less then .96 A/R housing. Car spools very fast and couldn't be more happy with it. Don't have any info to the 7875 unit . Both seem to do well
I can tell you this traction is a big issue without decent tires behind it lol. It has no lag and carrys the power threw the upper rpm's very well. I wouldn't go any less then .96 A/R housing. Car spools very fast and couldn't be more happy with it. Don't have any info to the 7875 unit . Both seem to do well
I'd love to run a bigger a/r, problem being that precision doesn't have a larger housing than a .96 for that turbo and I don't think Turbonetics does either in undivided. Then again not sure a larger a/r would help much anyways as the turbine wheel itself is still the restriction.