[Need4Camaro]

So I've decided I will eventually throw a Whipple on my SS, but I'm going to build it slowly and over time. My goal is to currently build it Heads/Cam/Stall and get it ready for the super charger install which will happen later. I will probably build the bottom end or swap in an LT4 short block as well, but this will all happen over time. Currently the SS is my DD, and although I do not have a commute, I still need as much 'up-time' as possible so the modifications will be more spread apart.

Need input.

Are Ported Heads enough or should I go with something else?
What Cam should I go with that will give me more power and still be within optimization for a Super Charger? Would any moderate NA cam work?
Also more importantly right now, what stall should I go with and which converter?

[GreyGhost702]

I think you need some greater detail to your build plan. Start with a power goal. How much power do you want to throw down in a daily driver? Keep in mind, the more complex the build and the higher the power, the more at risk reliability becomes. Can also be more expensive to drive, more frequent oil changes and worse fuel economy combined with exotic fuel needs. Fuel doesn't have to be a pain point if E85 is convenient, E85 can fund a lot of power (~1200whp or so) before needing to look at true race ethanol or other race fuels.

Also, are you DIY'ing this build or having a shop do it? You don't want to nickel & dime your build if you're having a shop do the work. Get it done all at once to be cost effective. Even as a DIY build, I highly recommend just purchasing the parts and accumulate them until you have the complete build. Since you are either swapping engines or building your shortblock, the engine has to come out which means everything comes off. No need to waste hardware and do the job multiple times over. Just more chances for things to go wrong.

IMO if you're going to use a LT4 shortblock, I think it might be more cost effective just to sell the SS and get a ZL1. You won't save any money getting a LT4 shortblock unless you're buying a used one, and I don't think that's worth doing unless you can get your hands a low mile one that you can confirm is in perfect order. That would be swapping it directly in. Even if you do that, while the LT4 is special, it still has its weak points. If you plan on pushing high power, it would be nice to have a real thrust bearing and stud the mains. PD's put a lot of abuse on the bottom end. In a DIY, the LT1 isn't bad to forge in terms of cost. I spent ~$2k on drop-ins, ~$600 hardware/seals, and $1200 on machine work. Doing the work on the LT1 eliminates the thrust bearing weakness and lets you align hone and stud the main. Now the LT1 will be better than a stock LT4 shortblock. I don't think you can even find a used LT4 shortblock for that price. If your block is in good shape and bores aren't too worn, you can do a drop-in set and turn down the compression ratio. If your pockets are deep, power goals tall, and you want to help beat the heat a PD cranks out, you could entertain a Katech (or prefered vendor) 416 shortblock. While the cost is significantly more, nothing is skimped on and it buys you the convenience of doing a direct swap, which will keep down-time to a minimum since you won't be waiting on machine work.

Again, depending on where/how you are sourcing the LT4 shortblock, if you're just aiming for ~600-800whp, you'll probably be fine on the OEM bottom end. If you're going to track the car on the weekends, you know you're putting your Daily Driver at risk anyway, so no need to beat that bush.

As far as installing these parts a bit at a time, I think it's a bit of a waste of money. Putting a cam in requires new head gaskets and hardware. And a waste of time/effort. A build is like putting together a symphony. All the parts should work together to support the build. In this case, the center piece is a PD blower. So the heads/cam should support PD FI. A NA cam will function, but it'll be incredibly inefficient. PD head units make a good chunk of boost right away. NA cams have a lot of overlap, which means you'll be dumping boost right out of the exhaust. If you were running a Centri blower, you could get away with it a little more. Centri's don't really make a lot of boost down low or mid range, they are linear so they make more as they rev. NA cam will help a Centri car get up the RPM range faster than it would otherwise with a PD cam profile. It's a small trade off for a Centri car to have that exhaust overlap. A bigger trade for a PD car. A PD cam won't "hurt" NA performance, you're just not going to be taking full advantage of the grind. Ported heads make all the difference in getting the most out of an aftermarket cam grind. Aftermarket head castings do have some advantages over a ported OE casting, but if your heads are in good shape, no cracks or defects, I'd stick with them. Aftermarket castings are expensive and you'd really only want them if you're going big power or competitive racing, IMO. The power gain potential differences will be marginal compared to cost.

I'm not an Auto guy so I can't really comment on the converter, but I would consult with whoever grinds the cam and take into consideration whether it's 100% street car, street/strip/track, or race car. Most important, whoever makes the converter will undoubtedly have the experience and knowledge to dial in your converter to what you want to do with your car.

And, if you can help it, buy a beater to Daily or to have as backup. It's hard to fund builds/repairs/unforeseen if you can't get to work.

[bishopts]

The way i always see it is what make the most power per dollar.
Cold air intakes for example. Spend $500 to $900 on cold air intakes to get maybe 12hp. Where you can spend that same amount on a tune and get double the power.
If you break down dollar per hp for any mod you can do the put them on a list broke down like that. Of course you wont really know exactly how much each one will do or how much one mod will make the other mod work better but just for a rough idea. It usually makes boost show its real value if you have it laid out like that.
Cam is usually pretty good dollar per hp vs heads. Add boost and heads dollar per hp is going to be less worth it. E85 will beat out heads easily. Add boost and e85 is even more worth it.
You also need to consider is this upgrade replacing a part that really is limiting power? Just because new heads are available do you even need them? Are you're ports so small they can't flow enough air? Is the valve size actually limiting volume? If you increase volume and decrease velocity will it make the new head less effective?
Also if you have more power can you get it to the ground? Or is beating the numbers on a dyno what you're chasing?
Break it down using logic.
1: dollar per hp
2: mods that support other mods
3: parts that are actually limiting power.
4: will more power actually make your car faster?

[KingLT1]

All you need is a drop in piston rod kit, super charger, and fuel system. PD cars work well with stock stall speed. BTR stage 1 is plenty of cam, you don't really need to do anything with the heads. Katech port program would be fine. It will make over 800whp on 12psi with Ethanol. And 950-1k @ 16psi. You don't have to get extravagant with the engine to make big power on this platform.

[Need4Camaro]

Originally Posted by GreyGhost702

I think you need some greater detail to your build plan. Start with a power goal. How much power do you want to throw down in a daily driver? Keep in mind, the more complex the build and the higher the power, the more at risk reliability becomes. Can also be more expensive to drive, more frequent oil changes and worse fuel economy combined with exotic fuel needs. Fuel doesn't have to be a pain point if E85 is convenient, E85 can fund a lot of power (~1200whp or so) before needing to look at true race ethanol or other race fuels.

Also, are you DIY'ing this build or having a shop do it? You don't want to nickel & dime your build if you're having a shop do the work. Get it done all at once to be cost effective. Even as a DIY build, I highly recommend just purchasing the parts and accumulate them until you have the complete build. Since you are either swapping engines or building your shortblock, the engine has to come out which means everything comes off. No need to waste hardware and do the job multiple times over. Just more chances for things to go wrong.

IMO if you're going to use a LT4 shortblock, I think it might be more cost effective just to sell the SS and get a ZL1. You won't save any money getting a LT4 shortblock unless you're buying a used one, and I don't think that's worth doing unless you can get your hands a low mile one that you can confirm is in perfect order. That would be swapping it directly in. Even if you do that, while the LT4 is special, it still has its weak points. If you plan on pushing high power, it would be nice to have a real thrust bearing and stud the mains. PD's put a lot of abuse on the bottom end. In a DIY, the LT1 isn't bad to forge in terms of cost. I spent ~$2k on drop-ins, ~$600 hardware/seals, and $1200 on machine work. Doing the work on the LT1 eliminates the thrust bearing weakness and lets you align hone and stud the main. Now the LT1 will be better than a stock LT4 shortblock. I don't think you can even find a used LT4 shortblock for that price. If your block is in good shape and bores aren't too worn, you can do a drop-in set and turn down the compression ratio. If your pockets are deep, power goals tall, and you want to help beat the heat a PD cranks out, you could entertain a Katech (or prefered vendor) 416 shortblock. While the cost is significantly more, nothing is skimped on and it buys you the convenience of doing a direct swap, which will keep down-time to a minimum since you won't be waiting on machine work.

Again, depending on where/how you are sourcing the LT4 shortblock, if you're just aiming for ~600-800whp, you'll probably be fine on the OEM bottom end. If you're going to track the car on the weekends, you know you're putting your Daily Driver at risk anyway, so no need to beat that bush.

As far as installing these parts a bit at a time, I think it's a bit of a waste of money. Putting a cam in requires new head gaskets and hardware. And a waste of time/effort. A build is like putting together a symphony. All the parts should work together to support the build. In this case, the center piece is a PD blower. So the heads/cam should support PD FI. A NA cam will function, but it'll be incredibly inefficient. PD head units make a good chunk of boost right away. NA cams have a lot of overlap, which means you'll be dumping boost right out of the exhaust. If you were running a Centri blower, you could get away with it a little more. Centri's don't really make a lot of boost down low or mid range, they are linear so they make more as they rev. NA cam will help a Centri car get up the RPM range faster than it would otherwise with a PD cam profile. It's a small trade off for a Centri car to have that exhaust overlap. A bigger trade for a PD car. A PD cam won't "hurt" NA performance, you're just not going to be taking full advantage of the grind. Ported heads make all the difference in getting the most out of an aftermarket cam grind. Aftermarket head castings do have some advantages over a ported OE casting, but if your heads are in good shape, no cracks or defects, I'd stick with them. Aftermarket castings are expensive and you'd really only want them if you're going big power or competitive racing, IMO. The power gain potential differences will be marginal compared to cost.

I'm not an Auto guy so I can't really comment on the converter, but I would consult with whoever grinds the cam and take into consideration whether it's 100% street car, street/strip/track, or race car. Most important, whoever makes the converter will undoubtedly have the experience and knowledge to dial in your converter to what you want to do with your car.

And, if you can help it, buy a beater to Daily or to have as backup. It's hard to fund builds/repairs/unforeseen if you can't get to work.

Currently my car runs off of flex fuel and I 99% of the time just use E85. Right now I average ~ 15 MPGish and for the most part I'm okay with it but its rare that I drive far.

Main reason it's going to be done over time is the build is likely going to take a few years to accumulate the parts, likewise I don't forsee myself trading cars anytime soon. My SS is paid off and I don't want another financed vehicle. I did the same thing with my 99 Z28. First I threw in a built trans, a few years down the road I threw in a cammed LS3 and stall converter, then years later I threw in a built rear axle, and a few years after that I Magnacharged it.

For the SS...
Powergoals: ~Anywhere between 700 - 800RWHP

I'm not too worried about how much it costs to drive it but decent reliability is a plus.

Right now my torque converter on my SS is failing and I want to replace it with a Stall Converter but not sure what to go with that will keep it consistent with my plans.

Heads & Cam will be done together, but later.

[Joshinator99]

Originally Posted by KingLT1

All you need is a drop in piston rod kit, super charger, and fuel system. PD cars work well with stock stall speed. BTR stage 1 is plenty of cam, you don't really need to do anything with the heads. Katech port program would be fine. It will make over 800whp on 12psi with Ethanol. And 950-1k @ 16psi. You don't have to get extravagant with the engine to make big power on this platform.

Agreed 100%

Originally Posted by Need4Camaro

Currently my car runs off of flex fuel and I 99% of the time just use E85. Right now I average ~ 15 MPGish and for the most part I'm okay with it but its rare that I drive far.

Main reason it's going to be done over time is the build is likely going to take a few years to accumulate the parts, likewise I don't forsee myself trading cars anytime soon. My SS is paid off and I don't want another financed vehicle. I did the same thing with my 99 Z28. First I threw in a built trans, a few years down the road I threw in a cammed LS3 and stall converter, then years later I threw in a built rear axle, and a few years after that I Magnacharged it.

For the SS...
Powergoals: ~Anywhere between 700 - 800RWHP

I'm not too worried about how much it costs to drive it but decent reliability is a plus.

Right now my torque converter on my SS is failing and I want to replace it with a Stall Converter but not sure what to go with that will keep it consistent with my plans.

Heads & Cam will be done together, but later.

If you need a converter call Circle D and get a Pro Series 258mm converter in the closest to stock stall range you can get. So just get one as close to stock stall speed as possible. That’ll be totally fine with a PD blower and it’ll be future proof too.

[GreyGhost702]

Originally Posted by Need4Camaro

Currently my car runs off of flex fuel and I 99% of the time just use E85. Right now I average ~ 15 MPGish and for the most part I'm okay with it but its rare that I drive far.

For the SS...
Powergoals: ~Anywhere between 700 - 800RWHP

I'm not too worried about how much it costs to drive it but decent reliability is a plus.

E85 and the whipple will get you to your power goal no sweat, don't even need the extra goodies (except the strengthening stuff). Of course you'll need the fuel system to support it. Probably big bore HPFP and some turned up LT4 injectors and in-tank pump upgrade. I don't think the LT4 in-tank pump will cut it at that level on E85 but a dual or tripple pump setup would and give you some future-proofing. 14-15 psi should effectively put you in the mid 700's and that's not asking too much of the 2.9 whipple. Some would argue to put a big cam in it while you're there, but a set of nice lifters/pushrods/trunion upgrade and a non-DOD/AFM LT4 spec cam would do the trick. Could save on head porting and retain full VVT function. Keeps reliability at the top as well keeping your power range OE, you'll make gobs of low-mid range torque and it'll still pull out to 6k just fine. Nice daily driver. With ported heads and a bigger cam, you can make the same power on a bigger pulley/less boost, more potential if/when you want to turn it up.

If you can find a LT4 shortblock you trust to do a direct swap, it should handle that power goal just fine unmodified. Not sure what all would go into putting a LT4 in a LT1 car, if it's a direct swap or not, or you need any harness adapters and stuff. I still think you're better off building up the LT1 if you're looking at crate LT4's. The stock LT1 could live at those power levels on E85 with a good tuner and good catch can setup. I'm sure someone around here does it.

As far as what order you put the parts on, of course you do you bro. I just suggest turning wrenches once. With PD upgrade build on a NA platform, there just aren't a whole lot of parts that are going to work by themselves well enough to justify putting them on ahead of the PD unit. Fuel system for example, more headache than it's worth to tune it down for NA power. I digress a bit for the in-tank stuff, while it'll need to be tuned down it certainly won't hurt to have that done ahead of time. It's quite the headache working on the in-tank setup from what I've read, and getting it set up right. One less thing to hassle with when you get the PD in the mail. Headers/exhaust could go on if it's not already there. If you're sticking with OE exhaust, I don't know if there's a difference between the LT4 cats and LT1 cats, might be worth looking into. Otherwise, Kooks makes good high output cats. Shouldn't have too much trouble on E85, though. Combustion temps should be kept in check. Otherwise there's not much else to it. You won't get much benefit running a PD cam without FI huffing on it. Some gains, but then you're paying for all those seals/hardware twice and potentially/likely pulling the engine twice. If you have to pull the engine for the converter then I guess it makes a little more sense. Still, 2x the hardware & seals.

[Need4Camaro]

Originally Posted by Joshinator99

Agreed 100%



If you need a converter call Circle D and get a Pro Series 258mm converter in the closest to stock stall range you can get. So just get one as close to stock stall speed as possible. That’ll be totally fine with a PD blower and it’ll be future proof too.

Why a PD Blower over a Whipple?

And if I did go Whipple, what stall should I go for?

Also for existing mods, I have CAI, Headers + Full Exhaust, E85 Tune

[Hostile_1LE]

Originally Posted by Need4Camaro

Why a PD Blower over a Whipple?

And if I did go Whipple, what stall should I go for?

Also for existing mods, I have CAI, Headers + Full Exhaust, E85 Tune

I think a whipple is a PD blower.

[m6-lt1]

Originally Posted by Need4Camaro

Why a PD Blower over a Whipple?

PD means positive displacement. A whipple is a PD blower. He just meant get a PD blower brand of your choice (whipple, Magnuson, etc). Post number 6 told you what stall to get.

[Need4Camaro]

Ok my mistake. When I see PD I am thinking Powerdyne. We used that same abbreviation for it in other car forums in relationship to supercharging so it registered to me as a Powerdyne unit over a Whipple

[Joshinator99]

Originally Posted by Need4Camaro

Why a PD Blower over a Whipple?

And if I did go Whipple, what stall should I go for?

Also for existing mods, I have CAI, Headers + Full Exhaust, E85 Tune

Originally Posted by Hostile_1LE

I think a whipple is a PD blower.

Originally Posted by m6-lt1

PD means positive displacement. A whipple is a PD blower. He just meant get a PD blower brand of your choice (whipple, Magnuson, etc). Post number 6 told you what stall to get.

Hostile_1LE and m6-lt1 have my back haha

Originally Posted by Need4Camaro

Ok my mistake. When I see PD I am thinking Powerdyne. We used that same abbreviation for it in other car forums in relationship to supercharging so it registered to me as a Powerdyne unit over a Whipple

Yeah I don’t think Powerdyne makes anything for our cars. Definitely meant positive displacement blower which a Whipple definitely is… I own one and can confirm. lol

As m6-lt1 said, post #6 tells you what I suggest for torque converter. PD blowers bring on torque and power very quickly, you don’t need stall speed like a centrifugal blower so as close to stock stall speed as you can get is perfect. My Circle D is just a few hundred RPM over stock because I make too much power to launch in first gear, so I use a bit of extra stall to get me moving with a 2nd gear launch.

[Need4Camaro]

Originally Posted by Joshinator99

Hostile_1LE and m6-lt1 have my back haha



Yeah I don’t think Powerdyne makes anything for our cars. Definitely meant positive displacement blower which a Whipple definitely is… I own one and can confirm. lol

As m6-lt1 said, post #6 tells you what I suggest for torque converter. PD blowers bring on torque and power very quickly, you don’t need stall speed like a centrifugal blower so as close to stock stall speed as you can get is perfect. My Circle D is just a few hundred RPM over stock because I make too much power to launch in first gear, so I use a bit of extra stall to get me moving with a 2nd gear launch.

Just dead curious what do ya'll think about Yank? I have one of those in my 99 Z28.

[KingLT1]

Yank, Circle D, FTI, all work well but I would keep stall speed under 3k, put a Mag or Whipple on it, do the fuel system, and run some E. It will make 680-700whp on the stock bottom end with 10psi. If you want more than that, put rods/pistons/cam in it. Can always do this part last.

I have been running the stock engine with a Whipple @ 10-11psi since 2019. It will handle some decent power if you take the proper precautions. Needs octane, cooling, and proper crank case ventilation. Any oil blowing back into the intake through the PCV side will cause detonation and kill the stock pistons fast. This is where the LT4 or a forged piston is much more forgiving. A catch can and Metco valve cover breather are a must.