To add a supercharger or not?

[garner7555]

As the title states, I have had the itch to add a supercharger for the past several months.  I'm sure most everyone can relate to wanting more power.  Below I will list my current setup that has about 1200 miles on it.

-440 block with factory steel crank and rods bored 0.030" with 2355 pistons
-The pistons sit 0.018" down in the hole and the valve reliefs account for 7cc dish
-I have sidewinder heads that advertise a 84cc chamber      http://www.mopartsracing.com/parts/Sidewinder.html
-My current head gaskets are 0.040"
All of this equates to 9.7:1 compression ratio and 0.058" quench if the calculators are correct.

I already have a different EFI setup ready to install that is capable of tuning with boost (this is a lot of why I'm looking at adding a supercharger)      https://www.edelbrock.com/pro-flo-4-xt-efi-kit-for-big-block-chrysler-rb-413-426-440-engines-black-35923.html
This setup is capable of supporting 975 HP with larger injectors and boost.  I am not looking to make anywhere near that much power, I just wanted to let people know about this option.
I really like the Edelbrock tuning software from the small amount of looking I have done.  For example, it gives you the ability to retard the timing based on the psi of boost.

Now to the real question, my compression is a little high for a boosted application.  What I am considering is running my current setup, other than a boost friendly cam change, and only running 3-5 psi of boost.  Do you think this is a possibility to work well?  I know that I will have to use an intercooler with the multi-port fuel injection.  Is anyone on here running boost on a setup remotely close to mine?

My goal would be to make 500 -550 hp at the flywheel.   With a better bottom end and lower compression ratio I could bump the boost levels up and make lots more power, but I don't really want to go that route currently.


supercharger setup  -   http://www.torqstorm.com/kits_single_big-block-mopar.html
I really like that they offer this as a kit with all accessories and serpentine belt setup that will fit behind the supercharger belt setup.  I have already been wanting to swap to serpentine belt setup.
I also like that this runs in it's own oil and doesn't use engine oil.

[Rolling_Thunder]

If you're trying to make 500-550hp then you don't need a supercharger...    you can make that number with a relatively mild 440 build.  -

[cdr]

As the title states, I have had the itch to add a supercharger for the past several months.  I'm sure most everyone can relate to wanting more power.  Below I will list my current setup that has about 1200 miles on it.

-440 block with factory steel crank and rods bored 0.030" with 2355 pistons
-The pistons sit 0.018" down in the hole and the valve reliefs account for 7cc dish
-I have sidewinder heads that advertise a 84cc chamber      http://www.mopartsracing.com/parts/Sidewinder.html
-My current head gaskets are 0.040"
All of this equates to 9.7:1 compression ratio and 0.058" quench if the calculators are correct.

I already have a different EFI setup ready to install that is capable of tuning with boost (this is a lot of why I'm looking at adding a supercharger)      https://www.edelbrock.com/pro-flo-4-xt-efi-kit-for-big-block-chrysler-rb-413-426-440-engines-black-35923.html
This setup is capable of supporting 975 HP with larger injectors and boost.  I am not looking to make anywhere near that much power, I just wanted to let people know about this option.
I really like the Edelbrock tuning software from the small amount of looking I have done.  For example, it gives you the ability to retard the timing based on the psi of boost.

Now to the real question, my compression is a little high for a boosted application.  What I am considering is running my current setup, other than a boost friendly cam change, and only running 3-5 psi of boost.  Do you think this is a possibility to work well?  I know that I will have to use an intercooler with the multi-port fuel injection.  Is anyone on here running boost on a setup remotely close to mine?

My goal would be to make 500 -550 hp at the flywheel.   With a better bottom end and lower compression ratio I could bump the boost levels up and make lots more power, but I don't really want to go that route currently.


supercharger setup  -   http://www.torqstorm.com/kits_single_big-block-mopar.html
I really like that they offer this as a kit with all accessories and serpentine belt setup that will fit behind the supercharger belt setup.  I have already been wanting to swap to serpentine belt setup.
I also like that this runs in it's own oil and doesn't use engine oil.

With ign timing control you should have no problem, might also put knock sensors on, my efi supports them, not sure if your set up does. no matter,,, BOOST IT !!!!!!

[garner7555]

If you're trying to make 500-550hp then you don't need a supercharger...    you can make that number with a relatively mild 440 build.  -

You are correct.  I already have a mild 440 and I want more power so I am considering boost rather than to basically start over.  I am leaning on the conservative side with those numbers, I didn't want anyone to get the false impression that I was expecting 850HP and for a factory bottom end to hold up to that.   

[garner7555]

As the title states, I have had the itch to add a supercharger for the past several months.  I'm sure most everyone can relate to wanting more power.  Below I will list my current setup that has about 1200 miles on it.

-440 block with factory steel crank and rods bored 0.030" with 2355 pistons
-The pistons sit 0.018" down in the hole and the valve reliefs account for 7cc dish
-I have sidewinder heads that advertise a 84cc chamber      http://www.mopartsracing.com/parts/Sidewinder.html
-My current head gaskets are 0.040"
All of this equates to 9.7:1 compression ratio and 0.058" quench if the calculators are correct.

I already have a different EFI setup ready to install that is capable of tuning with boost (this is a lot of why I'm looking at adding a supercharger)      https://www.edelbrock.com/pro-flo-4-xt-efi-kit-for-big-block-chrysler-rb-413-426-440-engines-black-35923.html
This setup is capable of supporting 975 HP with larger injectors and boost.  I am not looking to make anywhere near that much power, I just wanted to let people know about this option.
I really like the Edelbrock tuning software from the small amount of looking I have done.  For example, it gives you the ability to retard the timing based on the psi of boost.

Now to the real question, my compression is a little high for a boosted application.  What I am considering is running my current setup, other than a boost friendly cam change, and only running 3-5 psi of boost.  Do you think this is a possibility to work well?  I know that I will have to use an intercooler with the multi-port fuel injection.  Is anyone on here running boost on a setup remotely close to mine?

My goal would be to make 500 -550 hp at the flywheel.   With a better bottom end and lower compression ratio I could bump the boost levels up and make lots more power, but I don't really want to go that route currently.


supercharger setup  -   http://www.torqstorm.com/kits_single_big-block-mopar.html
I really like that they offer this as a kit with all accessories and serpentine belt setup that will fit behind the supercharger belt setup.  I have already been wanting to swap to serpentine belt setup.
I also like that this runs in it's own oil and doesn't use engine oil.

With ign timing control you should have no problem, might also put knock sensors on, my efi supports them, not sure if your set up does. no matter,,, BOOST IT !!!!!!

I was really happy when I saw that I could control timing in reference to boost psi.   As long as I'm very careful during tuning then that should prevent the rods from exiting the block.       If I wanted to be extra careful then I could have the timing tuned on a chassis dyno so we could monitor it much more closely.   

[garner7555]

The way I arrived at the 3-5 psi was from looking at some of the charts online.  I will post a link to them below.  I want to be able to run 93 octane pump gas.  I am at roughly 1000 feet elevation.


https://www.rpmoutlet.com/boost-compression-ratio-chart.htm

https://theblowershop.com/wp-content/uploads/2015/08/Effective_Compression.pdf

[myk]

Do it, DO IT!!!

[Challenger340]

Normally I wouldn't even bother saying anything at 3-5psi.... NOT a CONCERN !

But unfortunately "specific" to the L2355 Pistons very TIGHT Rec'd fit clrc's from factory ?.... AND your already 9.7:1 ? some due diligence to be careful may be warranted ?

Check your Piston to Wall clearance !
Because specific to the L2355's.... their rec'd .0015" to .002"  clrc if that's what you have ? may not be enough clearance for even 3-5 psi on top of the 9.7:1 static ?

[Challenger340]

The way I arrived at the 3-5 psi was from looking at some of the charts online.  I will post a link to them below.  I want to be able to run 93 octane pump gas.  I am at roughly 1000 feet elevation.


https://www.rpmoutlet.com/boost-compression-ratio-chart.htm

https://theblowershop.com/wp-content/uploads/2015/08/Effective_Compression.pdf

The ability to run whatever fuel is one thing.... let be for now the 3-5psi even being worth the added cost Versus performance increase ? that's for you to decide....
Nonetheless,
Your Piston to Wall clearance is entirely another matter, given... and especially with L2355's , their notoriously TIGHT rec'd fit ? and your already 9.7:1 static CR ?
just say'in....
Recommended Piston to Wall clearance when Machining the Engine for Boost increases for ALL Pistons as per the application ? as does Top Ring End-Gap ?
with...
Most 4032 Piston Manu's recommend an extra .001" to .003" be added to Piston to Wall Clrc in lieu of anticipated applications like: expected RPM... expected Heat... expected Compression Ratio and/or Boost or Nitrous ?
and also keep in mind...
4032 Forgings are generally speaking NOT recommended for anything but LOW Boost applications anyway ?

Given your stated current 9.7:1 C.R. ... and contemplated 5psi ?
IMO, you should maybe try and verify that you have at least .003"+ Piston to Wall clearance with some extra Ring End Gaps on your L2355's ? Because they fit even tighter than lots of stock 4.00" Bore Pistons do from factory ?
and remember...
HIGH Load/LOW rpm is the HARDEST thing on Connecting Rods.... FULL STOP !
That's why we don't like "loading" Engines on the Dyno down at lower rpm's... especially the stock "LY" Rod Engines ?
With good ARP Bolts I feel safer taking an LY Rod 6,500 rpm up top..... than I ever would loading the Dyno Brake on full down at 2,500 rpm !  Something else to contemplate with Boost down low on stock Rods ?

[garner7555]

The way I arrived at the 3-5 psi was from looking at some of the charts online.  I will post a link to them below.  I want to be able to run 93 octane pump gas.  I am at roughly 1000 feet elevation.


https://www.rpmoutlet.com/boost-compression-ratio-chart.htm

https://theblowershop.com/wp-content/uploads/2015/08/Effective_Compression.pdf

The ability to run whatever fuel is one thing.... let be for now the 3-5psi even being worth the added cost Versus performance increase ? that's for you to decide....
Nonetheless,
Your Piston to Wall clearance is entirely another matter, given... and especially with L2355's , their notoriously TIGHT rec'd fit ? and your already 9.7:1 static CR ?
just say'in....
Recommended Piston to Wall clearance when Machining the Engine for Boost increases for ALL Pistons as per the application ? as does Top Ring End-Gap ?
with...
Most 4032 Piston Manu's recommend an extra .001" to .003" be added to Piston to Wall Clrc in lieu of anticipated applications like: expected RPM... expected Heat... expected Compression Ratio and/or Boost or Nitrous ?
and also keep in mind...
4032 Forgings are generally speaking NOT recommended for anything but LOW Boost applications anyway ?

Given your stated current 9.7:1 C.R. ... and contemplated 5psi ?
IMO, you should maybe try and verify that you have at least .003"+ Piston to Wall clearance with some extra Ring End Gaps on your L2355's ? Because they fit even tighter than lots of stock 4.00" Bore Pistons do from factory ?
and remember...
HIGH Load/LOW rpm is the HARDEST thing on Connecting Rods.... FULL STOP !
That's why we don't like "loading" Engines on the Dyno down at lower rpm's... especially the stock "LY" Rod Engines ?
With good ARP Bolts I feel safer taking an LY Rod 6,500 rpm up top..... than I ever would loading the Dyno Brake on full down at 2,500 rpm !  Something else to contemplate with Boost down low on stock Rods ?

This is great advice and good information to have posted for anyone in the future.  I already knew about the ring end gaps, but I didn't know about the piston to wall clearance issues.  Thanks for the tips.     

This is currently just something I want to do and I may decide not to pull the trigger on it, but having all the facts and information like this will help me to decide.  If my piston to wall clearance isn't what it needs to be then I'm not sure what I would do.  If I needed to buy pistons, then it might make more sense to go with a stroker kit versus a supercharger.  Then again, I might decide to try to be content with my slow Charger and just continue to drive it as is.         

Keep the input coming guys, I have no experience with a supercharger.

[Challenger340]

The way I arrived at the 3-5 psi was from looking at some of the charts online.  I will post a link to them below.  I want to be able to run 93 octane pump gas.  I am at roughly 1000 feet elevation.


https://www.rpmoutlet.com/boost-compression-ratio-chart.htm

https://theblowershop.com/wp-content/uploads/2015/08/Effective_Compression.pdf

The ability to run whatever fuel is one thing.... let be for now the 3-5psi even being worth the added cost Versus performance increase ? that's for you to decide....
Nonetheless,
Your Piston to Wall clearance is entirely another matter, given... and especially with L2355's , their notoriously TIGHT rec'd fit ? and your already 9.7:1 static CR ?
just say'in....
Recommended Piston to Wall clearance when Machining the Engine for Boost increases for ALL Pistons as per the application ? as does Top Ring End-Gap ?
with...
Most 4032 Piston Manu's recommend an extra .001" to .003" be added to Piston to Wall Clrc in lieu of anticipated applications like: expected RPM... expected Heat... expected Compression Ratio and/or Boost or Nitrous ?
and also keep in mind...
4032 Forgings are generally speaking NOT recommended for anything but LOW Boost applications anyway ?

Given your stated current 9.7:1 C.R. ... and contemplated 5psi ?
IMO, you should maybe try and verify that you have at least .003"+ Piston to Wall clearance with some extra Ring End Gaps on your L2355's ? Because they fit even tighter than lots of stock 4.00" Bore Pistons do from factory ?
and remember...
HIGH Load/LOW rpm is the HARDEST thing on Connecting Rods.... FULL STOP !
That's why we don't like "loading" Engines on the Dyno down at lower rpm's... especially the stock "LY" Rod Engines ?
With good ARP Bolts I feel safer taking an LY Rod 6,500 rpm up top..... than I ever would loading the Dyno Brake on full down at 2,500 rpm !  Something else to contemplate with Boost down low on stock Rods ?

This is great advice and good information to have posted for anyone in the future.  I already knew about the ring end gaps, but I didn't know about the piston to wall clearance issues.  Thanks for the tips.      

This is currently just something I want to do and I may decide not to pull the trigger on it, but having all the facts and information like this will help me to decide.  If my piston to wall clearance isn't what it needs to be then I'm not sure what I would do.  If I needed to buy pistons, then it might make more sense to go with a stroker kit versus a supercharger.  Then again, I might decide to try to be content with my slow Charger and just continue to drive it as is.      

Keep the input coming guys, I have no experience with a supercharger.

Slow Charger ?
That is surprising given the Sidewinders/L2355 Pistons at 9.75:1 ?    

I don't know what Cam you are using ? but the Heads/Pistons would suggest close to 500 hp/500+ Ft/lbs Torque with the right Induction/Carb & Cam ?

Regarding the Blower..... all I'm saying is check your Piston to Wall Clrc ? Any chance the Machinist knows what clrc was used ?  
Normally 3-5 psi should be NO issue whatsoever on pretty much any Engine ?
The only "specifics" to yours flagging some caution being the higher than normally accepted CR at 9.75:1 for the Blower, and as mentioned... the rather "unique" TIGHT fit of the L2355 Forged Pistons ?

[garner7555]

Haha  The reason I put slow is because that is all relative to who you talk to.      Compared to a bone stock 69 Charger R/T my car is fast, but compared to many other things it is slow.  It's all just relative to someone's opinion.   I was hoping for 500HP when I assembled it but I think I am well below that, and swapping to this Multi port EFI may gain me some over my current throttle body injected EFI.  I hope to get my car on the scales and maybe the chassis dyno in the near future to see where I am at with it.   

The car runs extremely well and pulls hard, but we always want more.  I'm just considering what my next step toward wanting more should be.   

[70 sublime]

I have also been toying with the idea of a blower of some sort 

You have probably already seen these or past this point but I saved the links as there are some charts

https://www.onallcylinders.com/2013/01/31/blower-basics-part-1-supercharger-types-and-terms/

https://www.onallcylinders.com/2013/02/15/blower-basics-part-2/

https://www.onallcylinders.com/2013/03/15/blower-basics-part-3-tuning-and-upgrading-for-maximum-performance/

So now I can follow your thread to see what you come up with

[TexasStroker]

That is the beauty of the Pro-Flo 4 XT...it was made for boost.  Same reason I picked mine up.  As the build has sat I've mildly evolved.  I think it was 08 or 09 when I scored the heads...got the stroker crank and rods not long after.  Initial plan was to build an old school solid roller.  Still leaning that way, but opted to go with EFI.  And then when Edelbrock sprung the XT equipped Pro-Flo 4 I was thinking it would be the perfect intake to handle either the original build or a centrifugal.  For just supplementing what you've got the TorqStorm isn't a bad route to go.

I'd say go for it...Might be worth it to check around if anyone has installed one of the kits and see what it does to underhood temps etc.  Might just run the fuel line up the firewall and into a regulator to keep it away from most of the heat.

The Eddy software is very user friendly.

[c00nhunterjoe]

My only concern here despite any of the physical build specs is in the 1st statement of the op- "im only going to run 3-5 psi".... lol, dont kid yourself. A bone stock cast crank cast piston mill will live on 3 psi. But what is the point of spending thousands on boost to run 3 psi.... Bottom line- you will run 3 psi. Then 4 psi. Then 5 psi. And still be disappointed. 5 will will turn into 7, it wont ping so you will push to 10, and it will run great. You will post photos and videos on this site and others, then after a year or 2, pow, it scatters, and you are upset. But it will be a fun ride.

[INTMD8]

Not really too much compression for a centrifugal at low boost (as it builds linearly with rpm rather than instant like positive displacement).

That being said I think it will feel pretty soft at low psi.  If you're 3-5psi at redline it will have almost nothing off idle and mid range.

There are a few cars I've tuned (LS cars) with that brand head unit that had multiple failures.

Agree if you want 500-550, do it naturally aspirated.

[cdr]

Not really too much compression for a centrifugal at low boost (as it builds linearly with rpm rather than instant like positive displacement).

That being said I think it will feel pretty soft at low psi.  If you're 3-5psi at redline it will have almost nothing off idle and mid range.

There are a few cars I've tuned (LS cars) with that brand head unit that had multiple failures.

Agree if you want 500-550, do it naturally aspirated.

To make a REAL 550 hp NA with 440 cid, auto, AC, street car is not going to be user friendly. as for the brand of SC he wants to use I know nothing about them

[INTMD8]

Can't build a streetable 500 to 550hp naturally aspirated big block? 

Wouldn't think that is unreasonable but that's just me.

[cdr]

Can't build a streetable 500 to 550hp naturally aspirated big block? 

Wouldn't think that is unreasonable but that's just me.

this is a 440cid,,Guess I not as smart as you are.

[TexasStroker]

I was thinking the same as Joe...a lot of money for really low boost.  Looks cool, sounds cool, adds performance, but there is a lot left on the table.  Temptation to "just add a little more" would be ever present.

I'd still say go for it.  First sign of any issues, if funds allow, you can build up for higher boost.  Or, if it adds just enough and you love the sound...keep it as is and run it forever.  I know a lot of guys that have gone from a 383 or mild 440 to something really rowdy and ultimately come back down...everyone has a different point with streetability and end goals...problem is we never figure out without investing to that breaking point 

With the way the TorqStorm mounts it really simplifies the intake side with the XT though.  There are a few videos on YouTube of an AAR running around a track with one of their units...that guy might be able to provide you with some first hand feedback etc.

[INTMD8]

Just to add to the point above, yes you can do it but again, it's going to feel soggy unless you rev it out as a centrifugal builds boost with rpm.

And pullied for a few psi.... it will feel soggier on transition than naturally aspirated as there's enough cubes to nearly pull a vacuum on the induction after the blower at low rpm with that little boost.

Don't think you will like it, but I've been wrong before.

[INTMD8]

Can't build a streetable 500 to 550hp naturally aspirated big block?  

Wouldn't think that is unreasonable but that's just me.

this is a 440cid,,Guess I not as smart as you are.

Well I wouldn't presume that but I would also say I would put cubic inches down in the range of least importance when talking about horsepower. Power potential is going to come from heads/top end and a cam to match. Smaller cubes equals more rpm to get there.

That being said, even at 440ci you're not talking about a mind blowing hp per/ci goal here. Sidewinder heads as I read it flow around 260 out of the box, which isn't great but not a bad starting point.

For 500-550 crank, ideally I would change the pistons to bring compression closer to 11.5-1 (assuming matching cam).

If that's not possible, I would mill heads, port heads, and run a thinner gasket for say, .040 piston to head clearance. (if even possible, I don't know what the thinnest gasket is you can buy)

Would also guess but would be fine to be corrected on that the cam is not ideal, the pushrods are squishy and the valvesprings are soft.

Guess what I'm saying is, if you put 440ci into a decent compression range with some respectable flowing heads then match the cam/springs/pushrods to that combo I don't see why 500+ streetable crank hp is out of the question.

Not trying to discount your 512 but to my point, put stock iron heads and a stock cam in your engine and how much power does it make? Less than the same parts on a stock 440 because it peaks at a lower rpm...