Turbo's for my 5.3L impala
11-14-2013, 07:57 AM
#1
Teching In
Thread Starter
iTrader: (4)
Join Date: Jul 2012
Location: LaPorte, IN
Posts: 23
Likes: 0
Received 0 Likes
on
0 Posts
Turbo's for my 5.3L impala Ran across these https://ls1tech.com/forums/parts-cla...l#post17822838 in the classifieds section. Wanted to get some opinions on how they would perform on a 5.3L. I'm a little concerned about the .83 a/r housings for a twin 5.3L. This setup is going in my 64 impala and I'm looking to make about 600hp ttw. Thanks in advance for any opinions!
11-14-2013, 11:17 AM
#3
Those are my turbos! If you want super fast spool you might contact Denmah about the little turbos he had on his 6.0 that spooled so fast. Sarg on here too has a pretty big BW single that makes 15psi by 3700, thats excellent from what Ive seen, you might copy his setup.
11-14-2013, 11:30 AM
#4
Teching In
Thread Starter
iTrader: (4)
Join Date: Jul 2012
Location: LaPorte, IN
Posts: 23
Likes: 0
Received 0 Likes
on
0 Posts
Those are my turbos! If you want super fast spool you might contact Denmah about the little turbos he had on his 6.0 that spooled so fast. Sarg on here too has a pretty big BW single that makes 15psi by 3700, thats excellent from what Ive seen, you might copy his setup.
However, Hexen thinks they are a good size turbo(s) for setup and goals. I was/am concerned about the spool time with .83 a/r housings. A lot of what I'm reading people are using housings with a/r of around .68 for twin setups.
With that said, I don't participate in any form of racing. I mostly am doing this project for something to keep me busy during the winter. What are some of the pro's and con's I would experience if I were to use these in my setup.
11-14-2013, 11:47 AM
#5
People are using .68 A/R in twin setups on bigger turbos. Like I said before, A/R is a ratio, no an actual size. A turbo with a 1.15 A/R could have a smaller turbine than a bigger turbo with a .96 A/R. These are relatively small turbos. Even at .83, the turbines aren't very big.
Slower spool often means better street manners on a V8. Unless you need the fast spool to pull you off of the line at the track, then a slightly slower spool isn't an issue. Your car will behave like an NA car far more often. Less part throttle boost, better gas mileage around town. Put the foot down and have your power.
However, I don't think you're going to have an issue with these turbos. The guy selling them is doing so because he went with even bigger twins after all, not smaller ones.
Slower spool often means better street manners on a V8. Unless you need the fast spool to pull you off of the line at the track, then a slightly slower spool isn't an issue. Your car will behave like an NA car far more often. Less part throttle boost, better gas mileage around town. Put the foot down and have your power.
However, I don't think you're going to have an issue with these turbos. The guy selling them is doing so because he went with even bigger twins after all, not smaller ones.
11-14-2013, 11:49 AM
#6
Like I said in the other thread, Ive had a PT7675 on a 6.0 and Ive had these on a 6.0, both with manual transmissions. They'd both make right about 5psi at 3000rpm with a manual trans. Most people consider a PT7675 to be quick spooling on a 5.3. I dont really consider 5psi at 3000rpm that quick spooling though, but I think Im spooling retarded with every setup Ive done. 
11-14-2013, 12:59 PM
#7
Teching In
Thread Starter
iTrader: (4)
Join Date: Jul 2012
Location: LaPorte, IN
Posts: 23
Likes: 0
Received 0 Likes
on
0 Posts
People are using .68 A/R in twin setups on bigger turbos. Like I said before, A/R is a ratio, no an actual size. A turbo with a 1.15 A/R could have a smaller turbine than a bigger turbo with a .96 A/R. These are relatively small turbos. Even at .83, the turbines aren't very big.
Slower spool often means better street manners on a V8. Unless you need the fast spool to pull you off of the line at the track, then a slightly slower spool isn't an issue. Your car will behave like an NA car far more often. Less part throttle boost, better gas mileage around town. Put the foot down and have your power.
However, I don't think you're going to have an issue with these turbos. The guy selling them is doing so because he went with even bigger twins after all, not smaller ones.
Slower spool often means better street manners on a V8. Unless you need the fast spool to pull you off of the line at the track, then a slightly slower spool isn't an issue. Your car will behave like an NA car far more often. Less part throttle boost, better gas mileage around town. Put the foot down and have your power.
However, I don't think you're going to have an issue with these turbos. The guy selling them is doing so because he went with even bigger twins after all, not smaller ones.
Trending Topics
11-14-2013, 02:04 PM
#8
9 Second Club
And you also need to factor in camshaft, and transmission/gearing.
The 256's are the base turbo on the AGP twin kit for the new Camaro's and they spool fast on them apparently.
The 256's are the base turbo on the AGP twin kit for the new Camaro's and they spool fast on them apparently.
11-14-2013, 02:51 PM
#11
Thanks for the better explanation! So to expound on what you're saying, A/R is simply a ratio, which I understand, but you also need to take into consideration the size of the turbine (exhaust?) wheel as well. It indirectly affects the R in the equation. I understand R to be a function of the housing not the turbine wheel. however, a smaller turbine wheel would have a smaller housing and therefore a smaller Radius factor. Am I understanding what you're saying? It is difficult when people start throwing "turbo size" as bigger or smaller around its not always clear to me if they are referring to compressor size, turbine size, housing type, etc.
Wheel size will effect radius. Larger wheels will have more radius. Area is most often changed with a wider housing. Since the radius is effected by wheel size and the housing size can't be increased this way, the housing is often made wider. This decreases the velocity into the turbine (for spool) but increases the overall flow rate (for power).
This is why a larger turbo with a smaller A/R can still easily outflow a smaller turbo with a larger A/R. Its not that the housing is smaller, but the much larger housing radius can drive down the ratio even if the flow area is greater as well.