Power Mods Inquiry

Bronzehill · December 25, 2022

2015 Sierra 6.2 2WD 8 Speed.

I am split between Supercharger and Cam to do first.

Looking a semi driven vehicle with a power range of 500-600 WHP

Supercharger:

I am split between the 2650 Magnuson or the 2.9 Whipple Supercharger.

With the supercharger I read it would be best to upgrade to the LT4 Injectors and an HPFP.

- I see a varying of prices on LT4s also different fuel %. Are they all the same product just marketed at different? Also what would justify a higher fuel percentage?

Running E85 would also be a consideration to add to the update. I have it available all around.

CAM:

I am looking at a Stage 2 SC Cam. But this is where I am still trying to get my education in Lobe/Lift/Duration.

Also during this process would be doing a DOD/AFM Delete.

I have been reading several posts around regarding others builds and questions. I have gotten some direction.

I will be keeping stock headers or upgrading to something with Cats. I am looking for a mildly loud exhaust. MBRP is currently on it.

Thank you all in advance.

CajunFries · December 27, 2022

TVS 2650 > whipple. The TVS is more efficient and will make less heat. The Edelbrock’s kit will also come with a bigger heat exchanger. Can even turn it into a dual pass if you can find some local shop to do it.

Cam: email GPI and tell them your setup and they will spec you a cam that’ll fit your need. It’s an extra $25 to whatever cam kit you’ll get. I suggest staying with a low lift cam. You won’t be missing much power but your valvetrain will last a lot longer. Get the whole dual spring, CHE trunnion, Johnson lifters (NOT LS7 lifters!), 3/8 pushrods and etc. Do them right the first time and don’t worry about it again.

engine: Katech thermostat, NGK 6510 gapped them to 0.025”. OEM wires and coils are plenty but if you wanna get new wires, granatelli have some bad ass 0 ohms wires. Make sure they have heat sleeve on them or you can get some from Amazon. Cheap Chinese one will do.

exhaust: 1 7/8 of any brand you want. Don’t go with any smaller primaries. 3.5-4” for the rest of the exhaust. Vibrant GESI have high flow cats if whatever Longtube company doesn’t have any high flow cat Y/X pipe available. Straight thru mufflers no baffles styles. The more free flowing exhaust, the more easy power you’ll make.

Fuel: I suggest upgrading the in-tank pump to a TI automotive 535 (not 525 aka “hellcat” pump). It’s almost a direct replacement to the factory hanger/bucket. The OEM LT4 injectors and HPFP will do for 550-600hp with full E85. No need for oversize LT4 injectors or big bore HPFP.

Trans: Do the trans thermostat mod or get a lower temp Tstat. Adding a TruCool 40k wouldn’t hurt either.

Other supporting mod: Get yourself some traction bars. Either VAS or Caltrac. With more TQ, you don’t you want any axle wrap. Instead, use that force to give you traction. If you have an aluminum driveshaft , upgrading it to something stronger. PerformanceDriveline have a great piece and great customer service.

Bronzehill · December 29, 2022

Thank you for the indepth post. I have been researching alot of what you had written. More so looking at the low lift cams.

I did take your advise and moved away from the Whipple and looking to the TVS 2650. It has been back in forth with the SC in the Camaro and corvette forums, but more so of how much power they could obtain. I am more concerned with just achieving my goal with reliable nice sounding SC who can put consistent power down.

From what I read low lift cams tend to move the power higher up the RPMs. Not to big of an issue because I would imagine the SC would compensate power down low just fine. As well as with it being paired with a SC create unrealized HP. I would imagine not so much given I would not be running more than 8 PSI, but its still something I am reading into.

Plugs, Wires, Trunnion are all on the list. As well as my transmission service is due for a refresh and will be taking the to do what is needed then.

CajunFries · December 30, 2022

14 hours ago, Bronzehill said:

Thank you for the indepth post. I have been researching alot of what you had written. More so looking at the low lift cams.

I did take your advise and moved away from the Whipple and looking to the TVS 2650. It has been back in forth with the SC in the Camaro and corvette forums, but more so of how much power they could obtain. I am more concerned with just achieving my goal with reliable nice sounding SC who can put consistent power down.

From what I read low lift cams tend to move the power higher up the RPMs. Not to big of an issue because I would imagine the SC would compensate power down low just fine. As well as with it being paired with a SC create unrealized HP. I would imagine not so much given I would not be running more than 8 PSI, but its still something I am reading into.

Plugs, Wires, Trunnion are all on the list. As well as my transmission service is due for a refresh and will be taking the to do what is needed then.

Low lift cam doesn’t mean only power up top. It all depends on the spec. You can have low lift cam with all TQ if you want to. I’m not an expert or anything close to that but if you get with companies like GPI or cam motion and talk them, I’m sure they can get more in-depth about it and what they can do for you.

With a 2650 you can almost call it an overkill. That thing will make over 1000 without breaking a sweat. So no worry about if it’s going to be able to give you the power that you want/need. I ran a 2300 and it was a blast. 12psi on SBE, took my 6000lbs 2wd to the 1/8 in 7.8seconds. If it wasn’t 90+ degrees and will actually hook in the 60’, it’ll probably be able to do 7.5-7.6.

CamGTP · December 30, 2022

A TVS 1900 or TVS 2300 would do this man just fine too. Both will add tons of horsepower.

The 2650 is way overkill like he said.

Bronzehill · January 1, 2023

Not against the 2300 at all. I am open to the input yall have to offer.

What would be there difference between running the 2650 at a lower psi? To put equatable power down to the 2300?

-what would take 8lbs for 2300 take 5lbs for the 2650 (random numbers for psi)

this is genuine curiosity for an understanding perspective.

still waiting to hear back from Texas Speed and GPI to see what they would recommend but would like to be as informed as I can to know and explain what I am seeking. So again appreciate y’all’s time and replies.

AZ_SS · March 17, 2023

I went with the 3.0l whipple and couldn't be happier. With a custom intake and tune it made 474 rwhp. It did run out of injectors up top so is going back to Cordes for LT1 injectors at the end of the month. Its my daily so it probably won't be getting any other mods, so they said those will be plenty

CajunFries · March 18, 2023

8 hours ago, AZ_SS said:

I went with the 3.0l whipple and couldn't be happier. With a custom intake and tune it made 474 rwhp. It did run out of injectors up top so is going back to Cordes for LT1 injectors at the end of the month. Its my daily so it probably won't be getting any other mods, so they said those will be plenty

If you are already going up upgrade the injectors mind as well do LT4 injectors and HPFP. You’ll also need an intank pump. 535 from TI automotive/walbro is a good choice to go with. Easy drop in to the factory hanger. It is slightly longer than stock. Just need couple of self tap screws to hold the bucket in place and you’re set! That 3.0 can easily handle 4 digits. So let it eat!!!!!!

CajunFries · March 18, 2023

On 1/1/2023 at 2:22 PM, Bronzehill said:

Not against the 2300 at all. I am open to the input yall have to offer.

What would be there difference between running the 2650 at a lower psi? To put equatable power down to the 2300?

-what would take 8lbs for 2300 take 5lbs for the 2650 (random numbers for psi)

this is genuine curiosity for an understanding perspective.

still waiting to hear back from Texas Speed and GPI to see what they would recommend but would like to be as informed as I can to know and explain what I am seeking. So again appreciate y’all’s time and replies.

sorry I thought I replied to this way back…

Idk what the psi different it would be to make the same power. Boost is just a measurement of restriction so it might even be the same but you’ll need to spin the 2300 faster to make the same number.

Did you ever got around to boosting the truck?