Been turbo for a couple years now and....
Been turbo for a couple years now and.... I kind of hate the power delivery. I miss the gruntiness of H/C N/A. I need some advice from people with more experience and knowledge than I have.
Im debating at either going back to N/A which will kind of be a nightmare...orrrrrr im willing to change my setup a bit
My current setup is Huron Speed V3 kit with a turbonetics 78mm turbo, Tick stage 2 turbo cam and PRC 2.5 heads. I also have a Dana 60 with 4.11s. I have nothing but awesome things to say about the Huron kit...the kit itself is great and the company/Jonathan is spectacular, I just dont enjoy the car as much as I used to. I dont race it 1/4 or road course, just spirited driving on nice country roads. When i first did the turbo i just wanted more power as I was tired of my N/A setup. Now the car is kinda dead below 3800. Im not sure if its my cam choice, the current tune (done by a local shop) or just the size of the turbo itself.
Would a different cam and new tune make my power delivery that much different? Smaller turbo maybe? I dont know what to do. Its hard to get sideways now as the power comes on so high in the RPM range and so abruptly its kind of annoying.
Any advice? Im not super opposed to going back to N/A...I just want to enjoy the car more than I do now.
Also I am most likely going to go with a 6.0 whether I keep the turbo or not so that might help. Right now its just an LS1
Im debating at either going back to N/A which will kind of be a nightmare...orrrrrr im willing to change my setup a bit
My current setup is Huron Speed V3 kit with a turbonetics 78mm turbo, Tick stage 2 turbo cam and PRC 2.5 heads. I also have a Dana 60 with 4.11s. I have nothing but awesome things to say about the Huron kit...the kit itself is great and the company/Jonathan is spectacular, I just dont enjoy the car as much as I used to. I dont race it 1/4 or road course, just spirited driving on nice country roads. When i first did the turbo i just wanted more power as I was tired of my N/A setup. Now the car is kinda dead below 3800. Im not sure if its my cam choice, the current tune (done by a local shop) or just the size of the turbo itself.
Would a different cam and new tune make my power delivery that much different? Smaller turbo maybe? I dont know what to do. Its hard to get sideways now as the power comes on so high in the RPM range and so abruptly its kind of annoying.
Any advice? Im not super opposed to going back to N/A...I just want to enjoy the car more than I do now.
Also I am most likely going to go with a 6.0 whether I keep the turbo or not so that might help. Right now its just an LS1
You can have just as much grunt and more… Few things I’m noticing.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
Joined: Apr 2006
Posts: 3,909
Likes: 1,158
From: Grand Rapids, Michigan
What A/R is your turbo? We have similar combos ( mine is being built at the moment ). I went with a VS Racing 78/75 billet that has a .96A/R just because I know it will be more fun on the street. Yeah, it's going to choke early and limit maximum power, but I'm not going to worry about having soggy low RPM power. I'm also using a BTR Stage 2 turbo cam. In addition, I'm building my engine to be around 10.5:1 compression which will also be more responsive, but I'll have to run on E85. If you do have a larger A/R, you can get an exhaust housing with a smaller A/R for relatively cheap. The outlet is likely to be smaller, however, so you might have to adapt your downpipe or install a new one. I think that would be the easiest way to add more low end grunt. If you already do have a small A/R, then you might want to look into a smaller cam with an earlier IVC to build torque.
On The Tree
Joined: Feb 2022
Posts: 196
Likes: 72
From: Grand Rapids, MI
I have kinda noticed this as well with my setup since going turbo very recently. It used to be an insanely responsive NA combo that just brutalized tires, and now it seems like it takes 100hp to spin the turbo, but once it lights she GOES.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
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You can have just as much grunt and more… Few things I’m noticing.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
Yes sir
What A/R is your turbo? We have similar combos ( mine is being built at the moment ). I went with a VS Racing 78/75 billet that has a .96A/R just because I know it will be more fun on the street. Yeah, it's going to choke early and limit maximum power, but I'm not going to worry about having soggy low RPM power. I'm also using a BTR Stage 2 turbo cam. In addition, I'm building my engine to be around 10.5:1 compression which will also be more responsive, but I'll have to run on E85. If you do have a larger A/R, you can get an exhaust housing with a smaller A/R for relatively cheap. The outlet is likely to be smaller, however, so you might have to adapt your downpipe or install a new one. I think that would be the easiest way to add more low end grunt. If you already do have a small A/R, then you might want to look into a smaller cam with an earlier IVC to build torque.
I have kinda noticed this as well with my setup since going turbo very recently. It used to be an insanely responsive NA combo that just brutalized tires, and now it seems like it takes 100hp to spin the turbo, but once it lights she GOES.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
Thank you all for the replies. Im probably going to look at a 6.0 tomorrow local to me and i have some research to do.
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Verdad Gallardo On The Tree
Joined: Feb 2022
Posts: 196
Likes: 72
From: Grand Rapids, MI
Your cam is pretty big to be looking for response down low, especially with a 5.7L.
Do you have any exhaust leaks? Full bumper exit exhaust? Restrictive air filter? What size is the hotside piping just before the turbo? Is your wastegate cracking too early?
All of those will effect spool.
Now that I think about it I may just not be as aggressive on the go pedal because I am not used to the additional power(scared), where with the NA setup I would just stab the pedal right to the floor, double downshift and boogie.
With the turbo setup I am kind of rolling into it and waiting on the turbo for my power, as opposed to downshifting while NA. It is also cold so I am very traction limited below 50mph, hence the roll in. I think I just need to man up and jam on the go pedal.
Do you have any exhaust leaks? Full bumper exit exhaust? Restrictive air filter? What size is the hotside piping just before the turbo? Is your wastegate cracking too early?
All of those will effect spool.
Now that I think about it I may just not be as aggressive on the go pedal because I am not used to the additional power(scared), where with the NA setup I would just stab the pedal right to the floor, double downshift and boogie.
With the turbo setup I am kind of rolling into it and waiting on the turbo for my power, as opposed to downshifting while NA. It is also cold so I am very traction limited below 50mph, hence the roll in. I think I just need to man up and jam on the go pedal.
Teching In
Joined: Apr 2020
Posts: 24
Likes: 7
I'm running a stick shift LS1, 224/232 @114.5 LSA, BW S369 turbo rear mounted, pump 98 fuel, 4.11 gears (so similar set up to yours) and make 550rwhp/590ft/lbs on 9psi. Even with the rear mounted turbo with 275 wide tires, I have no traction when on boost in 2nd or 3rd gear. It makes the full 9psi before 3500rpm. I don't think you need to do anything else but go a smaller turbo.....
That is the one thing I have always found irritating about some of the turbo threads. People talk about how their combo has no problem spooling X size turbo, so newbies think that is what they need. On a truly street driven vehicle, having a 1000hp capable turbo just means you wasted a lot of engine bay space and sucked all the fun out of driving from one stoplight to the next. The OP would likely be very happy with a much smaller turbo. Of course the same thing happens with cam threads, so you combine the two and have a miserable driving experience.
Your cam is pretty big to be looking for response down low, especially with a 5.7L.
Do you have any exhaust leaks? Full bumper exit exhaust? Restrictive air filter? What size is the hotside piping just before the turbo? Is your wastegate cracking too early?
All of those will effect spool.
Now that I think about it I may just not be as aggressive on the go pedal because I am not used to the additional power(scared), where with the NA setup I would just stab the pedal right to the floor, double downshift and boogie.
With the turbo setup I am kind of rolling into it and waiting on the turbo for my power, as opposed to downshifting while NA. It is also cold so I am very traction limited below 50mph, hence the roll in. I think I just need to man up and jam on the go pedal.
Do you have any exhaust leaks? Full bumper exit exhaust? Restrictive air filter? What size is the hotside piping just before the turbo? Is your wastegate cracking too early?
All of those will effect spool.
Now that I think about it I may just not be as aggressive on the go pedal because I am not used to the additional power(scared), where with the NA setup I would just stab the pedal right to the floor, double downshift and boogie.
With the turbo setup I am kind of rolling into it and waiting on the turbo for my power, as opposed to downshifting while NA. It is also cold so I am very traction limited below 50mph, hence the roll in. I think I just need to man up and jam on the go pedal.
Yeah man you need to smash the pedal lol....these cars are pretty predictable while losing traction even in boost.
I'm running a stick shift LS1, 224/232 @114.5 LSA, BW S369 turbo rear mounted, pump 98 fuel, 4.11 gears (so similar set up to yours) and make 550rwhp/590ft/lbs on 9psi. Even with the rear mounted turbo with 275 wide tires, I have no traction when on boost in 2nd or 3rd gear. It makes the full 9psi before 3500rpm. I don't think you need to do anything else but go a smaller turbo.....
That is the one thing I have always found irritating about some of the turbo threads. People talk about how their combo has no problem spooling X size turbo, so newbies think that is what they need. On a truly street driven vehicle, having a 1000hp capable turbo just means you wasted a lot of engine bay space and sucked all the fun out of driving from one stoplight to the next. The OP would likely be very happy with a much smaller turbo. Of course the same thing happens with cam threads, so you combine the two and have a miserable driving experience.
Thank you guys again for the responses
TECH Regular
Joined: Feb 2002
Posts: 426
Likes: 45
From: ohio
Along with a 4.11 gear, and a manual transmission, 4 strikes. Smaller turbo, stock gears, smaller cam will make it much better. None of that combo you have works well at the power level you are making. The gear doesn’t work at all with a turbo and manual transmission on the street.
Smaller turbo and possibly a gear change. If it has a cam and a decent valve spring don't be obsessed with power under 3500rpm, spin it to 7000+ Low RPM torque is an easy way to hurt a motor.
You can have just as much grunt and more… Few things I’m noticing.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
First off is 560hp with a 78mm at 9lbs? Is that the power level you want? If so, you don’t need/want a 78/75 turbo. Put an S366 on there and it will light off MUCH quicker. Other wise turn the turbo up a ton. A 78/75 isn’t likely in its “happy zone” at 9lbs. You should be running closer to 20. If you don’t want more power, and you just want it sooner… again… wrong turbo.
The wrong converter totally destroys a turbo setup. What do you run? What does the converter flash to if you just stomp the gas from a stop.
Also turbos are load dependent. So a 4.11 won’t load the motor much down low.
Step one, put a smaller turbo on if you re happy with your power level. Step 2 get a good converter, step 3 run a 3.73…
lastly the tune can have A LOT to do with spool characters. You can have a turbo setup that feels like it’s a healthy 13:1 BBC if you set it up right.
TECH Addict
Joined: Dec 2004
Posts: 2,178
Likes: 627
From: Florida
i have too much of a good thing then. 2.73 gear, 5.3 twin 6061s and when it had a manual trans it was super lazy til the turbos woke up.
OP, post your tune if possible just to see where its at, as an example mine has pretty aggressive timing out of boost to get the turbo going.
My LS1/TH400 S484 combo is a bit lazy down low but starts building boost around 3,500rpm and builds it stupid fast when brake boosting so it may be a combination of tune, parts and driving technique in your case.
TECH Enthusiast
Joined: Mar 2013
Posts: 503
Likes: 39
Hey,I resent that! Besides, I think my problem was with you talking about loading the turbo and not the engine. BTW, aren't engines load dependent also?
Last edited by gsteele; Mar 1, 2024 at 04:49 PM.
All wrong combo for the build. The right turbo, the right cam, the right gear, the right tune will make the car night and day. Who tuned it? I'd be willing to be a gear change and a good tune would wake the car up significantly before changing turbos or cams out. That said, you dont need a 78mm turbo for 550whp. What do you shift at?
On The Tree
Joined: Feb 2022
Posts: 196
Likes: 72
From: Grand Rapids, MI
I have kinda noticed this as well with my setup since going turbo very recently. It used to be an insanely responsive NA combo that just brutalized tires, and now it seems like it takes 100hp to spin the turbo, but once it lights she GOES.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
10.8:1CR 6.0L, 216/220 114LSA cam, 4l80, 3.27 gear, 3000 stall. 7875 1.25AR. I feel like a need a touch more converter and my shift tables need to be adjusted because I can make boost at 30% throttle and it will downshift mid pull as I am increasing the throttle. My timing is very soft because ive only got 93 octane, more timing and e85 will come with bigger injectors. I was expecting lots of boost by 3000 but cant seem to get any before 3700 or so.
I have changed some of the lockup settings in my tune so the converter clutch will stay locked under more throttle(like a manual trans) and I am "spooling" (positive manifold pressure) about 1000 rpm sooner. Seems like TheBallSS is right with the load spooling turbos. My stall was creating artificial rpm with not much load, but once I locked up and opened the throttle more it is spooling sooner.