LS4 build
Moderators: The Dark Side of Will, Series8217
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Re: LS4 build
Running a quick power/time/capacity convergence calculation:
Average Power Production for my make-believe engine between 3000 to 7500 RPM is around 400HP 400HP accelerating from 0-135MPH (top of 4th gear in my make believe transmission) in a 2800lb car takes 15 seconds.
(2800lb/(32.2ft/s^2)*(135-0mph*1.466(ft/s)/mph)^2/(400HP*550ft-lb/s/HP)=15s
While running a 160F thermostat,
400HP into the coolant, with a 35GPM cooling system, for 15s will raise 3.5Gal (14 qts - the Fieros cooling system capacity) temperature by 4738 BTU/min; to a top tank temp of 208F. The 35GPM pump has a cooling power of 288HP at that top tank temperature. It will take 6s to return the system to 160F at that flow.
Stepping up to a 55GPM pump flow changes the cooling power to 321HP, and the 15s run leaves the top tank at 194F, and the system takes 3.8s to return to 160F.
The 35GPM pump is marginal at best for long term WOT sessions.
20GPM is worse, 229F top tank, and 11s cooldown, with a cooling power of 238HP.
There are some flaws in this math to workout, and I am purposely ignoring how the radiator functions during all of this.
Average Power Production for my make-believe engine between 3000 to 7500 RPM is around 400HP 400HP accelerating from 0-135MPH (top of 4th gear in my make believe transmission) in a 2800lb car takes 15 seconds.
(2800lb/(32.2ft/s^2)*(135-0mph*1.466(ft/s)/mph)^2/(400HP*550ft-lb/s/HP)=15s
While running a 160F thermostat,
400HP into the coolant, with a 35GPM cooling system, for 15s will raise 3.5Gal (14 qts - the Fieros cooling system capacity) temperature by 4738 BTU/min; to a top tank temp of 208F. The 35GPM pump has a cooling power of 288HP at that top tank temperature. It will take 6s to return the system to 160F at that flow.
Stepping up to a 55GPM pump flow changes the cooling power to 321HP, and the 15s run leaves the top tank at 194F, and the system takes 3.8s to return to 160F.
The 35GPM pump is marginal at best for long term WOT sessions.
20GPM is worse, 229F top tank, and 11s cooldown, with a cooling power of 238HP.
There are some flaws in this math to workout, and I am purposely ignoring how the radiator functions during all of this.
car.
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Re: LS4 build
I also found a great deal recently on a LS9 coolant/oil heat exchanger.
My pan currently has a AN adapter block from improved racing, this might package better, maybe. Ill have to measure it, when it arrives.
My pan currently has a AN adapter block from improved racing, this might package better, maybe. Ill have to measure it, when it arrives.
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- Peer Mediator
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Re: LS4 build
That's shown on the dry sump pan. Will it work on a wet sump pan?
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Re: LS4 build
From what I gather, yes. But wet sump pans lack some of the mounting pads. Edelbrock's offers it in some supercharger kits, they include this oil cooler with thier kits and a special bracket for the pan rail.
https://www.summitracing.com/parts/EDL-15905
https://www.corvetteforum.com/forums/c6 ... -cars.html
Becuase I'm making everything more difficult, I bought off of a friend years ago, an entire Dry sump LS3 system, pan, pump, tank and some aftermarket adapters from an install in a RX7.
I bought a Factory LS3 dry sump crankshaft as well. Since ata the time it was the cheapest forged steel crankshaft you could get ($470) PN should be in my first post of this thread.
https://www.summitracing.com/parts/EDL-15905
https://www.corvetteforum.com/forums/c6 ... -cars.html
Becuase I'm making everything more difficult, I bought off of a friend years ago, an entire Dry sump LS3 system, pan, pump, tank and some aftermarket adapters from an install in a RX7.
I bought a Factory LS3 dry sump crankshaft as well. Since ata the time it was the cheapest forged steel crankshaft you could get ($470) PN should be in my first post of this thread.
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Re: LS4 build
Further research shows that the wet and dry sump LS3 pan are different enough to not be compatible. The Wet sump pan has vertical walls, the dry sump pan is tapered. The mounting ears for the LS7/LS9 oil cooler will interfere with the pan.The Dark Side of Will wrote: ↑Wed Sep 20, 2023 8:15 pm That's shown on the dry sump pan. Will it work on a wet sump pan?
The LSA oil cooler fits wet sump pans and has mounts proud of the pan walls. With bracketry they should fit the standard LS4 pans.
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- Peer Mediator
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Re: LS4 build
Now you have an excuse to go dry sump!FieroWanaBe1 wrote: ↑Thu Sep 21, 2023 2:19 pmThe Wet sump pan has vertical walls, the dry sump pan is tapered. The mounting ears for the LS7/LS9 oil cooler will interfere with the pan.The Dark Side of Will wrote: ↑Wed Sep 20, 2023 8:15 pm That's shown on the dry sump pan. Will it work on a wet sump pan?
Is the LSA pan too deep? Is there a reason it won't bolt up to an LS4 block?FieroWanaBe1 wrote: ↑Thu Sep 21, 2023 2:19 pm The LSA oil cooler fits wet sump pans and has mounts proud of the pan walls. With bracketry they should fit the standard LS4 pans.
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Re: LS4 build
The LS4 pan is actually about an inch shallower at 5.5". About an 1" shallower than the L99 or LSA pans, but I dont think that would prevent anyone from using that pan in a swap with fieroguru's starter bracket.The Dark Side of Will wrote: ↑Thu Sep 21, 2023 2:27 pm
Now you have an excuse to go dry sump!
Is the LSA pan too deep? Is there a reason it won't bolt up to an LS4 block?
The vette LS3 pan would be the shallowest though at 5"
And LS4King's pan has a bolt together starter solution. And has good baffles for the pickup tube.
I already have all the parts for the full factory dry sump system. I'm sticking to it. I just need some mods to fix the issues people see at the track. The pan can be sucked dry and the factory level of de aeration needs help.
Improved Racing offers improved windage tray and baffles for the pan. And Avaid has a tank insert to help seperate air better. Increasing tank capacity also was a solution used by Katech, and implemented in a odd way by Chevrolet eventually by adding an auxiliary oil tank.
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Re: LS4 build
From what I have been able to ascertain, the LS6 block and the L33 share the most in common, and the L33 5.3L has been called a budget LS6 block in the pre Gen-IV internet lore. The LS4 appears to be part of this lineage, with the addition of AFM, given its release time, it must have been a GenIII.5 development.
In the LS6, the liners appear to be about 1/2 inside the aluminum bore and 1/2 proud of the bottom bore, the liner appears to double in thickness at the top, it still looks like its cast in and has ribs to retain the liner.
The top of the liner appears to have less "thickness" from the bore to the liner OD in an LS6 engine than my LS4.
The bottom of the bore is a machined surface into the aluminum at a larger OD than the bore, and the LS4 has a 3.9" diameter at that area, so there is very likely more meat there than the LS6 block. Perhaps they do share cast in liners, and differ only in machining. the top portion, from my old pictures and this cross section support this assessment Here is a fresh machined ebay block bored .020 over, easier to see the top of the liner.
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Re: LS4 build
I pulled out my Dry sump pan and tank.
My pan doesnt have the mounting provisions cast in. I will need to make myself a bracket to support the cooler, if it all fits. My tank is also the all cast syle, as opposed to the one with the plastic top half. There is probably a weight penalty associated with the aluminum version. It alsos lacks the port used for the auxiliary oil tank added to later dry sump units.
My pan doesnt have the mounting provisions cast in. I will need to make myself a bracket to support the cooler, if it all fits. My tank is also the all cast syle, as opposed to the one with the plastic top half. There is probably a weight penalty associated with the aluminum version. It alsos lacks the port used for the auxiliary oil tank added to later dry sump units.
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Re: LS4 build
Jegs had its house brand camshafts on sale.
I purchased this one that i had my eyes on.
PN 555-200585
Lift: 0.612"/0.612"
Duration @ 0.050": 236°/246°
Advertised Duration: 298°/309°
Lobe Separation: 110°
RPM Range: 2,000-6,500 RPM
Pretty aggressive duration and a tighter LSA than most LS cams. Should make a lot of peak power...
I purchased this one that i had my eyes on.
PN 555-200585
Lift: 0.612"/0.612"
Duration @ 0.050": 236°/246°
Advertised Duration: 298°/309°
Lobe Separation: 110°
RPM Range: 2,000-6,500 RPM
Pretty aggressive duration and a tighter LSA than most LS cams. Should make a lot of peak power...
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- Shaun41178(2)
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Re: LS4 build
That will prob peak close to 6800 if you have the intake manifold to support it.
It's gonna have some serious chop at idle
It's gonna have some serious chop at idle
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Re: LS4 build
For the moment I would like to try and stuff my TBSS/GenIV truck intake under the decklid, but I doubt I can make enough clearance.
The backup would be a BTR Equalizer, or Fast LsxR but those are spendy.
It looks like this cam is Jeg's version of the GM LSX454 Crate Motor Cam.
https://www.yellowbullet.com/threads/ls ... 2.2402370/
The backup would be a BTR Equalizer, or Fast LsxR but those are spendy.
It looks like this cam is Jeg's version of the GM LSX454 Crate Motor Cam.
https://www.yellowbullet.com/threads/ls ... 2.2402370/
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