Help! Turbo sizing for 5.3 - Specs inside
* 2003 5.3 stock rod/pistons/crank, ~8.75:1
* Milled 317 heads
* Comp Cam 233/239 .59x/.605 114 LSA, dual valve springs
* 80lb injectors
* ls6 intake
* 4l80 w/3xxx stall
The car is a daily driver (drive everywhere, rain, snow, etc) for now, but may eventually transfer to being a toy. I'm not afraid of a little lag, but I want it to be decent out of the hole. The car will see some track action, but not it's primary purpose. As far as HP goals, it's hard to say, of course I want lots

I will probably transfer a 6.0 or larger in eventually, so going a bit too big for a 5.3 is ok. I'm also split between going with a t4 or t6, pros and cons to both. I was thinking of a s480 b/w, Precision 7675 and even possibly going with an oil-less 80mm. I'm leaning towards an 80mm, but haven't seen a lot of people posting about them on the 5.3's.
What would you all suggest?
This is a bone stock bottom and 317 heads, car is a little lazy but boost comes in HARD @ around 3500rpm's....
I made a couple of passes and the best 60ft i could get was a 2.0 leaving with no boost (6lbs and pumpgas).....
I see no issue with running a 80mm on a 5.3, goodluck!
This is a bone stock bottom and 317 heads, car is a little lazy but boost comes in HARD @ around 3500rpm's....
I made a couple of passes and the best 60ft i could get was a 2.0 leaving with no boost (6lbs and pumpgas).....
I see no issue with running a 80mm on a 5.3, goodluck!
I got a best of 7.44 @ 105 and 11.0 @ 135 with car nosing over about 100ft or so before the traps, i guess i didnt put enough gas in the car and it started to run out lol!
* 2003 5.3 stock rod/pistons/crank, ~8.75:1
* Milled 317 heads
* Comp Cam 233/239 .59x/.605 114 LSA, dual valve springs
* 80lb injectors
* ls6 intake
* 4l80 w/3xxx stall
The car is a daily driver (drive everywhere, rain, snow, etc) for now, but may eventually transfer to being a toy. I'm not afraid of a little lag, but I want it to be decent out of the hole. The car will see some track action, but not it's primary purpose. As far as HP goals, it's hard to say, of course I want lots

I will probably transfer a 6.0 or larger in eventually, so going a bit too big for a 5.3 is ok. I'm also split between going with a t4 or t6, pros and cons to both. I was thinking of a s480 b/w, Precision 7675 and even possibly going with an oil-less 80mm. I'm leaning towards an 80mm, but haven't seen a lot of people posting about them on the 5.3's.
What would you all suggest?
If you plan to upgrade the motor later down to the road to 6.0 and larger....then no reason not to go 80mm to start with.
Trending Topics
The Best V8 Stories One Small Block at Time







