Smallish LS-R head package...
Moderator: Team
-
- Guru
- Posts: 1575
- Joined: Mon Apr 04, 2011 8:54 pm
- Location: central Florida
Re: Smallish LS-R head package...
Yes correct answer. This shows us that a cylinder head with excellent design can make a LOT of H.P. with valves of moderate size. Mark H.
Re: Smallish LS-R head package...
The nice thing about the All Pro part #'s I recommended is two nice features.
1. The LSW-1 -12 cylinder head is that it can be supplied with its smaller as cast intake runner and uncut seats and a 2.100 or 2.125" valve can be setup and the runner can be held to a smaller minimum area.
2. The Hurricane tall runner intake is a split two piece design and comes again unported, so again runner cross sections can be held to smaller areas and the longer more even length crooked leg runners will allow a total intake port length that can be matched with the ideal camshaft to place maximum torque numbers in the 4000 - 4500 rpm range and still allow peak power near the 7000-7500 rpm range.
The 11.8 to 1 compression ratio will be the largest impediment to seeing 800hp with a 370 cubic inch limit even with the best heads and camshaft selections. JMHO
1. The LSW-1 -12 cylinder head is that it can be supplied with its smaller as cast intake runner and uncut seats and a 2.100 or 2.125" valve can be setup and the runner can be held to a smaller minimum area.
2. The Hurricane tall runner intake is a split two piece design and comes again unported, so again runner cross sections can be held to smaller areas and the longer more even length crooked leg runners will allow a total intake port length that can be matched with the ideal camshaft to place maximum torque numbers in the 4000 - 4500 rpm range and still allow peak power near the 7000-7500 rpm range.
The 11.8 to 1 compression ratio will be the largest impediment to seeing 800hp with a 370 cubic inch limit even with the best heads and camshaft selections. JMHO
The Older I Get, The Dumber I Get
-
- Member
- Posts: 144
- Joined: Fri Jun 17, 2016 2:28 am
- Location:
Re: Smallish LS-R head package...
790fwhp from a 376 Ls3 with 12.5 compression at or about 8800. Me personally having 7-8 thousand into a set of heads for a smaller cubic inches engine is a waste. You can bump the comp up yet 7500 Rpm will be your down fall. BTW the heads listed need cams in the lift range of + .850 to take advantage of the better layout. 750fwhp at 7500 Rpm is the typical range for a 408-416 with 11.5 compression. 800 with the same combination with more compression 12.5+ with or about 8k for Rpm. Those heads on a 370 would have no Tq and only Rpm would help which kills your idea of 7500 Rpm. The builds above use Ls3 and 7 heads. Got both sets for a 408 to make 750 and 800.
-
- Member
- Posts: 144
- Joined: Fri Jun 17, 2016 2:28 am
- Location:
-
- Expert
- Posts: 796
- Joined: Sat Jun 30, 2012 3:12 am
- Location: Canada
Re: Smallish LS-R head package...
Yes they should work fine for that although depending on the luck of the draw with castings. 2.125" might be pushing the limit for minimum as cast throat size.
LSR is a great head casting and the intake exhaust runner is plenty small enough for the job. A 370 inch would run spectacular with a set of those done right.
I have done a few sets for pro street typae stuff with 2.200 int on a large bore and smaller port areas.
That head will make power!
LSR is a great head casting and the intake exhaust runner is plenty small enough for the job. A 370 inch would run spectacular with a set of those done right.
I have done a few sets for pro street typae stuff with 2.200 int on a large bore and smaller port areas.
That head will make power!
-
- Guru
- Posts: 6386
- Joined: Tue Jul 24, 2012 11:15 am
- Location: Roseville, Michigan (just north of Detroit)
- Contact:
Re: Smallish LS-R head package...
Thank you ... THAT is one specific thing I needed to know.induction apprentice wrote: ↑Mon Oct 29, 2018 1:20 am Yes they should work fine for that although depending on the luck of the draw with castings. 2.125" might be pushing the limit for minimum as cast throat size.
That head will make power!
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
Re: Smallish LS-R head package...
Is that LSR head going to qualify as an "inline" head as well?Walter R. Malik wrote: ↑Mon Oct 29, 2018 10:08 amThank you ... THAT is one specific thing I needed to know.induction apprentice wrote: ↑Mon Oct 29, 2018 1:20 am Yes they should work fine for that although depending on the luck of the draw with castings. 2.125" might be pushing the limit for minimum as cast throat size.
That head will make power!
-
- Member
- Posts: 144
- Joined: Fri Jun 17, 2016 2:28 am
- Location:
Re: Smallish LS-R head package...
No canted heads. I'm waiting for someone to describe the build needed to make 750-800 with a 6.0 with 7500 Rpm. Those heads after port work will run $4k without parts. Valves will be $1500 add rockers and springs. Intake runs $900.
Re: Smallish LS-R head package...
I understand that, but his rule set may be vague again.Rowdy Yates wrote: ↑Mon Oct 29, 2018 10:57 am No canted heads. I'm waiting for someone to describe the build needed to make 750-800 with a 6.0 with 7500 Rpm. Those heads after port work will run $4k without parts. Valves will be $1500 add rockers and springs. Intake runs $900.
-
- Member
- Posts: 144
- Joined: Fri Jun 17, 2016 2:28 am
- Location:
-
- Guru
- Posts: 6386
- Joined: Tue Jul 24, 2012 11:15 am
- Location: Roseville, Michigan (just north of Detroit)
- Contact:
Re: Smallish LS-R head package...
NO ... those heads are a true "canted" valve head but, similar in design to the later D3 Ford heads which have only a canted intake valve.CGT wrote: ↑Mon Oct 29, 2018 10:51 amIs that LSR head going to qualify as an "inline" head as well?Walter R. Malik wrote: ↑Mon Oct 29, 2018 10:08 amThank you ... THAT is one specific thing I needed to know.induction apprentice wrote: ↑Mon Oct 29, 2018 1:20 am Yes they should work fine for that although depending on the luck of the draw with castings. 2.125" might be pushing the limit for minimum as cast throat size.
That head will make power!
As you know, in that venue, the numbers down at 4,000 to 5,500 RPM are just as important as those at the top.
Choosing the better head specifically for those rules as written, ("NOT inline but, NOT canted"), seems to have been a bad Idea if those C3's are going to be forced to run against true "canted valve / hemi" heads in the higher class, anyway; even with their low intake port.
It amounts to being penalized for taking advantage of the WRITTEN rules; oh well.
Last edited by Walter R. Malik on Mon Oct 29, 2018 6:42 pm, edited 1 time in total.
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
Re: Smallish LS-R head package...
No, does not quite say it all because this was a 370 cubic inch Bonneville engine designed to turn 9000 rpms with 15.0 to 1 compression and no camshaft specifications listed I am sure for a reason, that's intellectual property and was one of the big keys to this engine making that kind of power at that rpm. I would like to see the dyno printout of where peak torque occured.
I think what Walter might be asking for here is not a 9000 rpm Bonneville spec engine.
This engine in this article built by Venom was a great result from a very good spec. and build, but I still think it's still a little like comparing apples and oranges.
I think what Walter might be asking for here is not a 9000 rpm Bonneville spec engine.
This engine in this article built by Venom was a great result from a very good spec. and build, but I still think it's still a little like comparing apples and oranges.
The Older I Get, The Dumber I Get
-
- Member
- Posts: 144
- Joined: Fri Jun 17, 2016 2:28 am
- Location:
Re: Smallish LS-R head package...
Just looking at the Rpm in which 800 is or was made. He did ask for 800 @ or about 7500 if I'm not mistaken. So if you shorten the Cam to the listed 7500 Rpm would it make more HP.... No. The compression listed is pretty high also if he's thinking of a higher compression. With the heads he's wanting to use I'd say that the build listed said 750 ish at or about 7500, he'd have more Tq as the shorter Cam has a 7500 peak he's wanting to use.