350 top end build
Thread Starter
Heel & Toe
Joined: Dec 2017
Posts: 19
Likes: 0
From: Canada
350 top end build
Hey guys I have a 77 with an l 48 in it. I’m looking to make about 400hp when I’m done with it. The car currently has a 600 dual feed double pumper quick fuel, dual plane performer intake headers and duals with glass packs for mufflers. I also put a 2500 b&m stall In it. Now I was going to order a pair of promaxx heads (185cc, 64cc) with a comp cam (.490 lift) and an MSD RTR unit for it. (Links below) do you guys think this combination will produce 400 flywheel hp? Any opinions are highly appreciated thanks for your help!!http://www.jegs.com/i/ProMaxx-Perfor.../2168/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
Racer
Joined: Nov 2017
Posts: 289
Likes: 32
Hey guys I have a 77 with an l 48 in it. I’m looking to make about 400hp when I’m done with it. The car currently has a 600 dual feed double pumper quick fuel, dual plane performer intake headers and duals with glass packs for mufflers. I also put a 2500 b&m stall In it. Now I was going to order a pair of promaxx heads (185cc, 64cc) with a comp cam (.490 lift) and an MSD RTR unit for it. (Links below) do you guys think this combination will produce 400 flywheel hp? Any opinions are highly appreciated thanks for your help!!http://www.jegs.com/i/ProMaxx-Perfor.../2168/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
Not with the water pump, fan, power steering pump, and alternator attached.
Burning Brakes
Joined: Jul 2014
Posts: 831
Likes: 54
From: Arlington TX
I agree with Jim. However, depending on the age of the internals, I'd be worried about the rings withstanding that high compression. What compression will you be shooting for?
Last edited by Strokemyaxe; Dec 5, 2017 at 12:53 PM.
Pro
Joined: Mar 2014
Posts: 529
Likes: 113
From: Texas
750 Carb, 190cc/64cc heads, MSD RTR is good. Cam: Xtreme Energy 284H Hydraulic Flat Tappet Camshaft Complete Kit Lift: .507"/.510" Duration: 284°/296° RPM Range: 2300-6500, 2500 stall converter is good.......10.5 compression......93 octane fuel....
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Race Director
Joined: Jan 2003
Posts: 18,341
Likes: 101
Hey guys I have a 77 with an l 48 in it. I’m looking to make about 400hp when I’m done with it. The car currently has a 600 dual feed double pumper quick fuel, dual plane performer intake headers and duals with glass packs for mufflers. I also put a 2500 b&m stall In it. Now I was going to order a pair of promaxx heads (185cc, 64cc) with a comp cam (.490 lift) and an MSD RTR unit for it. (Links below) do you guys think this combination will produce 400 flywheel hp? Any opinions are highly appreciated thanks for your help!!http://www.jegs.com/i/ProMaxx-Perfor.../2168/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
http://www.jegs.com/i/COMP-Cams/249/K12-246-3/10002/-1
http://www.jegs.com/i/MSD-Ignition/121/8360/10002/-1
http://www.superchevy.com/how-to/463...-engine-build/
http://www.superchevy.com/how-to/463...gine-build-ii/
http://www.superchevy.com/how-to/463...ine-build-iii/
Thread Starter
Heel & Toe
Joined: Dec 2017
Posts: 19
Likes: 0
From: Canada
Hey everyone sorry about the long reply time I accidentally double posted and was looking at the other thread! Thank you all for the input!!
I’ll be shooting for a CR of 9:1 and will also be adding roller rockers to the list!
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Maybe and probably not 400 HP. At least not at any reasonable RPM.
The dish pistons on the L-48 are not good for any rasonable power production. They are cast pistons good for a steady 350 HP. Above that it's a gamble. No squish pad either so detonation may become an issue.
A FT cam is also a gamble, expecially the Extreme series. They have a propensity for wiping a lobe.
Roller cam with roller rockers, those heads for a roller cam with straight plugs (unless angled plugs is what you want), flat top pistons, refreshed bottom end, and then you'd be in the 400 HP range at around 5500 RPM. And it might actually last a while.
The dish pistons on the L-48 are not good for any rasonable power production. They are cast pistons good for a steady 350 HP. Above that it's a gamble. No squish pad either so detonation may become an issue.
A FT cam is also a gamble, expecially the Extreme series. They have a propensity for wiping a lobe.
Roller cam with roller rockers, those heads for a roller cam with straight plugs (unless angled plugs is what you want), flat top pistons, refreshed bottom end, and then you'd be in the 400 HP range at around 5500 RPM. And it might actually last a while.
Race Director
Joined: Jan 2003
Posts: 18,341
Likes: 101
Maybe and probably not 400 HP. At least not at any reasonable RPM.
The dish pistons on the L-48 are not good for any rasonable power production. They are cast pistons good for a steady 350 HP. Above that it's a gamble. No squish pad either so detonation may become an issue.
A FT cam is also a gamble, expecially the Extreme series. They have a propensity for wiping a lobe.
Roller cam with roller rockers, those heads for a roller cam with straight plugs (unless angled plugs is what you want), flat top pistons, refreshed bottom end, and then you'd be in the 400 HP range at around 5500 RPM. And it might actually last a while.
The dish pistons on the L-48 are not good for any rasonable power production. They are cast pistons good for a steady 350 HP. Above that it's a gamble. No squish pad either so detonation may become an issue.
A FT cam is also a gamble, expecially the Extreme series. They have a propensity for wiping a lobe.
Roller cam with roller rockers, those heads for a roller cam with straight plugs (unless angled plugs is what you want), flat top pistons, refreshed bottom end, and then you'd be in the 400 HP range at around 5500 RPM. And it might actually last a while.
.......COMPLETELY...... well thought out reasoning in this post too.Today is a LONG WAY from when those GM Budget priced flat tappet cam Crate motor build stories were posted. Those were done more than 20 years ago. As of 2017? There is really no good reason or argument that suggests any thing less than a roller cam motor is a good starting point.
Last edited by Krystal; Dec 24, 2017 at 09:01 AM.