New Heart for Scarlet

[boofhead]

Indeed. Unless the owner wants to chase even higher power so there is room to go to higher hp if desired though higher risks.

[Husky65]

Yep, good explanation.

So better heads = less boost ... and therefore less strain on other components like pistons & head gaskets etc.

It means less boost, but, you should really be upping the boost. Otherwise you might as well go NA imo.
If you have 10psi and are making 400rwhp for eg, and go high flowing heads, you might make 450rwhp on 8 psi for eg. But I could have just increased my boost to 14psi and made 450rwhp with the old heads.

To me that's the whole point of boost. I don't understand people running low boost on big dollar motors. Good pistons, gaskets and a tune and you can run a lot of boost safely. And it saves you building a top dollar NA system.

I just don't see the point of spending 3g on high flowing heads to increase power, when I could have done the same increasing boost.

Scarlet is a bit different, because he is going for 1000hp. So even with his heads he is going to max that Novi 2000 out

[gbx78]

Yep, good explanation.

So better heads = less boost ... and therefore less strain on other components like pistons & head gaskets etc.

It means less boost, but, you should really be upping the boost. Otherwise you might as well go NA imo.
If you have 10psi and are making 400rwhp for eg, and go high flowing heads, you might make 450rwhp on 8 psi for eg. But I could have just increased my boost to 14psi and made 450rwhp with the old heads.

To me that's the whole point of boost. I don't understand people running low boost on big dollar motors. Good pistons, gaskets and a tune and you can run a lot of boost safely. And it saves you building a top dollar NA system.

I just don't see the point of spending 3g on high flowing heads to increase power, when I could have done the same increasing boost.

Scarlet is a bit different, because he is going for 1000hp. So even with his heads he is going to max that Novi 2000 out

Haha now now lets not get carried away here.

I do like the idea of being totally streetable while not on boost and what 15-20psi then adds to it should i enter that territory.. at the end of the day im hooked on supercharger wine whether 4psi or 20.. sounds great at idle and worth it hehe

[Pinto-Pete]

Could have saved your money and just put a gilmer drive set up on your water pump and alternator for "that" sound...

[Charbel]

It might cost a bit more, but if you can achieve the same power with less boost the greatest benefit is the reduction in intake temp and thus detonation issues. More boost = more heat. Hotter the intake temp, increases pre-ignition.

[Husky65]

Yeah but then why boost it. For eg a novi 2000 is rated at 1400cfm and 26psi. Why would build a motor so you only have to run it at 10psi (this is not in relation to GBX, just an example). You can fix intake temps with an intercooler or meth. You can get discharge temps lower than ambient with certain cooling methods, so I don't see that as an issue if you actually take care of it properly.
Forced induction is literally adding cubes inches to your motor when boosting. Just build the motor to handle the boost. I don't know, that's how I see it.

[gbx78]

Yeah intake temps are covered nicely by meth injection

[gbx78]

Could have saved your money and just put a gilmer drive set up on your water pump and alternator for "that" sound...

Hehe well actually i got my novi for about the same price but with extra features like air shoving capabilities.

Ill be going down a pulley size for this exercise which will put me slightly over the 'advertised' max impeller speed but paxton tell me the novi 2k can handle it plus a little more.

[Charbel]

I understand what you're saying and for a gear head making power then it makes sense to just turn up the boost tap. From an efficiency point of view, there is something to gain from low boost applications, and that gain in efficiency has tended to disappear with increased boost. Traditionally anyway...Modern boosted cars are doing all sorts of different things.

Charlie

[boofhead]

Great discusion. A few points to remember

1 gbx if he pushed his engine is already at 500plus HP so desiring more power within reasonable engineering limits requires a stronger block. He has never ever pushed it just babied it so the new block can be without fear.

2 Since the new block is able to handle 1000hp then targeting 600plus hp on low boost is very safe. Now medium boost aka 1 bar [14.7psi] is what we are designing for this build. The target is 800hp. Every thing in the car is setup for that figure aka fuel system diff ebrakes etc. i fully expect to hit that target but if more boost needed then so be it. In my own boosted cars I always limited them to 15psi as it is a great performance increase while still being safe for the engine while still being enjoyable to drive [with moderate throttle movement]. The compression, gaskets etc is setup with 1 bar in mind. Note: in NA form it will not be as powerful as if it was built for NA only.

3 gbx drives in cruise mode most of the time and often has passengers so it needs to behave well and be easy to drive in traffic. I do not want him to loose the simple enjoyment of the car just to say you have a particular number.

5 the novi tends to get a lot of belt slippage as the boost rises. Current it is max 10psi and slippage is an issue. No point in pushing it to much higher.

On a dyno and more boost 1000hp could be possible but on the street 500 is scary enough - maybe I am getting to old.

It is being built for the fun of it so I really do not care what the number is. it is for fun and complete the dream.

[Dwayne]

He has never ever pushed it just babied it.

3 gbx drives in cruise mode most of the time

?

[Husky65]

Great discusion. A few points to remember

1 gbx if he pushed his engine is already at 500plus HP so desiring more power within reasonable engineering limits requires a stronger block. He has never ever pushed it just babied it so the new block can be without fear.

2 Since the new block is able to handle 1000hp then targeting 600plus hp on low boost is very safe. Now medium boost aka 1 bar [14.7psi] is what we are designing for this build. The target is 800hp. Every thing in the car is setup for that figure aka fuel system diff ebrakes etc. i fully expect to hit that target but if more boost needed then so be it. In my own boosted cars I always limited them to 15psi as it is a great performance increase while still being safe for the engine while still being enjoyable to drive [with moderate throttle movement]. The compression, gaskets etc is setup with 1 bar in mind. Note: in NA form it will not be as powerful as if it was built for NA only.

3 gbx drives in cruise mode most of the time and often has passengers so it needs to behave well and be easy to drive in traffic. I do not want him to loose the simple enjoyment of the car just to say you have a particular number.

5 the novi tends to get a lot of belt slippage as the boost rises. Current it is max 10psi and slippage is an issue. No point in pushing it to much higher.

On a dyno and more boost 1000hp could be possible but on the street 500 is scary enough - maybe I am getting to old.

It is being built for the fun of it so I really do not care what the number is. it is for fun and complete the dream.

I agree, I think 15psi(ish) is a great number for a boosted application. By low I meant 10psi and under.
See, your going about it the right way. You have a boost figure in mind and are building the motor to that. That's how you do it efficiently and cost effectively.
Sort of can't wait till I get mine running so I can blow the block to pieces and get a dart block.

I'm surprised there is belt slippage at 10psi. I thought novi's were pretty good in regards to belt slip. Is it and 8 rib or 10 rib?

[gbx78]

Thanks for taking the time to writeup boof.. i havent really been clear with my goals in my original posts cept ' look ..pretty bits' typing on a smart phone proves to be challenging with my fat fingers and cant be asked for it!..

So .. what he said ^^^^ yes purpose built with boost levels 15psi in mind. The idea was, other than the trans the rest of the car is setup for an easy 800hp and the novi is good for ridiculous levels of boost and hp so thought lets aim for that whereby in my cruise mode, which to be honest noone drives at 6500 in each gear everytime they get in there car.. but the idea of being a streetable cruiser on one end and then an animal on the other end ahould i want to floor it is appealing. (whether i use it or not / need or not isnt the purpose of the build.)

Huskey, sometimes noticing some belt slip in the logs at the top end..
Its 10rib.. i may not have the tensioner tight enough but it feels pretty tight and as per paxtons instructions..but as I understand too tight causes load on the bearings and premature (tee hee) wear or damage.. so could be an issue there. But not too worried at the moment. Paxton tell me belt slip at the top end is expected and somewhat by design to protect the hardware but saying that.. i am looking at cog setup just the same.

Im running the larger crank pulley (8") and 3.5 sc pulley. Also I suspect with my oil leak into the valute area is reducing my performance as im gettng oily or greasy air out of the bov... . Gotta change out the seals before the build starts..

Will be an interesting build and process.. numbers arent the objective but a starting point to get matching parts to work efficiently together.

[hybrid]

How do you know it's slipping? That honestly surprises me. I've got an 8-rib belt and it doesn't slip.
If yours is slipping with a 10-rib at 10lbs, something is surely wrong.

[gbx78]

How do you know it's slipping? That honestly surprises me. I've got an 8-rib belt and it doesn't slip.
If yours is slipping with a 10-rib at 10lbs, something is surely wrong.

At one point the logs showed steady increase in boost with drops and then increases at top end (when i was getting 8psi).. at that time i dont think my belt was tight enough and i bottomed out on the tensioner. Have since put a shorter belt and i think its ok now as i dont see those drops anymore. I think boof mentioned it as a comment not so much that im having problems with it currently but more so to keep in mind.

My biggest issue now is leaking SC seals. Need to sort that out.