[radz28]

Originally Posted by Z OH 6

Thanks everyone for your input. I think I have all the answers I need. We can keep the discussion going if you wish but I think in the end the result is still that it's going to be a very negligible gain at best without more boost and fuel on a 2650R. I have the standard Kong port on the OEM blower and the car is pullied making 700whp at 14-15psi of boost through 2" headers and Green high flow cats. I dont honestly think I need more power because I'm at the limit of the street tires traction now and I don't want to run a drag radial all the time to enjoy the car. I was considering the 2650R for the more consistent MATs but that's very pricey to upgrade to the 2650R for that small gain. I think the 2650R doesn't make sense until I'm ready to do a cam, if I ever make that decision.

Yeah. Since you're happy with how it is, I don't think anyone being honest would try to sell you on spending money on a 2650. I'm not certain you'd gain much, and you'll probably find a lot of people agreeing with you.

[JasonGofast]

If you're drag racing, roll racing and chasing times at the strip or on the street the LT4 will do better than the 2650 until you start pushing higher numbers like 850+. Cordes, AMP, and other shops that work on big builds have proven it many times. The LT4 will have more torque on low end and hit harder. Will it stay cool as easily? Definitely not. As I said before the 2650 will put out consistent times run after run. If you're just putting around town though you won't notice a difference in temps. My IATs still get high on my 2650 until I'm cruising at speed.

My first mod from stock was a 2650 with headers, 103 tb, 5" intake, and a low side. I made 705 right at redline. The power delivery is different from stock. I remember clearly when I first got my car back I thought it felt slower driving around town. Peak torque was higher and it definitely had grunt, but driving around at low rpms the difference was noticeable. What I also noticed was once I got past 5k rpms it felt like the hand of god started pushing the car from behind. So where you lose bottom end the top end is much greater.

The 2650 is just overkill without proper fueling. I'm now pushing 900whp+ with mine and I think it's fantastic. However, while I was at 700 it seemed like nothing more than a show piece. I do think it made for a better weekend car for cruises and backroads. If you're planning on staying at the same power level you're better off just doing cooling mods than getting a 2650.

[Z OH 6]

Originally Posted by JasonGofast

If you're drag racing, roll racing and chasing times at the strip or on the street the LT4 will do better than the 2650 until you start pushing higher numbers like 850+. Cordes, AMP, and other shops that work on big builds have proven it many times. The LT4 will have more torque on low end and hit harder. Will it stay cool as easily? Definitely not. As I said before the 2650 will put out consistent times run after run. If you're just putting around town though you won't notice a difference in temps. My IATs still get high on my 2650 until I'm cruising at speed.

My first mod from stock was a 2650 with headers, 103 tb, 5" intake, and a low side. I made 705 right at redline. The power delivery is different from stock. I remember clearly when I first got my car back I thought it felt slower driving around town. Peak torque was higher and it definitely had grunt, but driving around at low rpms the difference was noticeable. What I also noticed was once I got past 5k rpms it felt like the hand of god started pushing the car from behind. So where you lose bottom end the top end is much greater.

The 2650 is just overkill without proper fueling. I'm now pushing 900whp+ with mine and I think it's fantastic. However, while I was at 700 it seemed like nothing more than a show piece. I do think it made for a better weekend car for cruises and backroads. If you're planning on staying at the same power level you're better off just doing cooling mods than getting a 2650.

Yea, I've got all upgraded AFCO heat exchangers. Looks like I'll leave it alone for now. I may go with off road pipes at some point which I think would net me about 10whp.

[Z OH 6]

Originally Posted by radz28

Yeah. Since you're happy with how it is, I don't think anyone being honest would try to sell you on spending money on a 2650. I'm not certain you'd gain much, and you'll probably find a lot of people agreeing with you.

Thanks, I really appreciate everyone's honesty. I've seen these debates several times and even offered my own opinion several times, but its always been about the value of using a stock ported blower up to a certain hp level and when its just better to go with the 2650R. I think I just had a few questions in the back of my mind about whether the cooling benefits of the 2650R were worth it at 700whp and I see that's probably not the case.

[Smokin19]

Originally Posted by Z OH 6

Thanks everyone for your input. I think I have all the answers I need. We can keep the discussion going if you wish but I think in the end the result is still that it's going to be a very negligible gain at best without more boost and fuel on a 2650R. I have the standard Kong port on the OEM blower and the car is pullied making 700whp at 14-15psi of boost through 2" headers and Green high flow cats. I dont honestly think I need more power because I'm at the limit of the street tires traction now and I don't want to run a drag radial all the time to enjoy the car. I was considering the 2650R for the more consistent MATs but that's very pricey to upgrade to the 2650R for that small gain. I think the 2650R doesn't make sense until I'm ready to do a cam, if I ever make that decision.

We will find out what a BMR stg.ll 38% cam will be like with a Kong X port on my build. I really am at the limit of the green I want to spend, so I nixed the 2650R at this time. I also feel this will be the max build I will want for the street.

[CW3SF]

Originally Posted by Z OH 6

Thanks everyone for your input. I think I have all the answers I need. We can keep the discussion going if you wish but I think in the end the result is still that it's going to be a very negligible gain at best without more boost and fuel on a 2650R. I have the standard Kong port on the OEM blower and the car is pullied making 700whp at 14-15psi of boost through 2" headers and Green high flow cats. I dont honestly think I need more power because I'm at the limit of the street tires traction now and I don't want to run a drag radial all the time to enjoy the car. I was considering the 2650R for the more consistent MATs but that's very pricey to upgrade to the 2650R for that small gain. I think the 2650R doesn't make sense until I'm ready to do a cam, if I ever make that decision.

Just curious on your set up…. did you also upgrade the heat exchanger? And if you wanted better cooling at this point in your build would it be beneficial to do the upgraded slanted cooling bricks?

[radz28]

Originally Posted by CW3SF

Just curious on your set up…. did you also upgrade the heat exchanger? And if you wanted better cooling at this point in your build would it be beneficial to do the upgraded slanted cooling bricks?

I believe ZL1s come with those bricks, if I understand what you're saying.

[CW3SF]

Originally Posted by radz28

I believe ZL1s come with those bricks, if I understand what you're saying.

I’m taking about upgraded bricks. Here’s an example.


https://www.crracing.com/product/lt4...rcooler-bricks

[Z OH 6]

Originally Posted by CW3SF

Just curious on your set up…. did you also upgrade the heat exchanger? And if you wanted better cooling at this point in your build would it be beneficial to do the upgraded slanted cooling bricks?

I have all upgraded AFCO heat exchangers. The upgraded bricks in the stock blower are an expensive upgrade. Porting the stock blower makes sense because its relatively cheap for the amount of power you gain, but upgrading the coolant bricks doesn't seem to provide much bang for the buck. I would rather just move to the 2650R than dump more money into the stock blower.

[CW3SF]

Originally Posted by Z OH 6

I have all upgraded AFCO heat exchangers. The upgraded bricks in the stock blower are an expensive upgrade. Porting the stock blower makes sense because its relatively cheap for the amount of power you gain, but upgrading the coolant bricks doesn't seem to provide much bang for the buck. I would rather just move to the 2650R than dump more money into the stock blower.

I totally get that. I’m just thinking about max cooling improvement for the stock blower, where cost isn’t a consideration. Personally I won’t swap over to a 2650 until I’m ready to break into the motor and do a cam and a full fuel system. But I might give the cooling bricks a go while I’m running a max effort stock blower.

[laynlo15]

Hey it was a great discussion and if your happy we're happy for you.

[Z OH 6]

Originally Posted by laynlo15

Hey it was a great discussion and if your happy we're happy for you.

[EDFHOBBIES]

The only thing I notice over the stock blower with a 9.17 lower was in the higher rpm band it keep pulling to 7000 and would of kept doing so. The oem blower had a feeling of running out of fuel or needing to shift close to 1000 rpm lower. I did a stock(9.17) to stock 2650 swap the hp was within 20 of each other. If you go see video 3 of Mikes testing you will see the rpm bands between the 1.7, 2.3, and 2.65.. He described what I could feel.


I'm sure porting a stock blower fixes that issue.. but as mentioned earlier if your running a ported 1.7 and some meth with no cam your 700s Mike made 800s with meth more efficiently and probably less boost.

[Camaro1973]

Originally Posted by Z OH 6

Thanks, I really appreciate everyone's honesty. I've seen these debates several times and even offered my own opinion several times, but its always been about the value of using a stock ported blower up to a certain hp level and when its just better to go with the 2650R. I think I just had a few questions in the back of my mind about whether the cooling benefits of the 2650R were worth it at 700whp and I see that's probably not the case.

At 700, the benefit would be the cooling. Past this, when you wake it up with a cam, ported heads this is where its going to shine and where the stock blower begins to strain.


Yes you can still make similar power on the stock blower, but doing it efficiently is a completely different story.


I went straight to the 2650 first, i contemplated porting the blower etc. I thought i was going to stay around 700 too. But of course that never happened. I figured if i was going to do anything down the road i would be in much better shape with the 2650 instead of the stock blower. Quite frankly, i know many people who spent alot porting their blowers, multiple trips for additional work for them to just remove the stock blower in the end and replace it with a 2650 or something else.


For me, its about efficient, being able to run max timing on a given fuel etc. And here I am adding a chiller now to keep the air charge temps down as low as possible. Well see how that goes.


I'm sure its worth it. From 85-60 degrees, i've dropped an entire half second and a bit more off my 60-130 times.