AFR 260cc on a 6.0? - LS1TECH - Camaro and Firebird Forum Discussion

Notices
Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

AFR 260cc on a 6.0?

Old 10-11-2018, 06:12 PM
  #1  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default AFR 260cc on a 6.0?

I've recently acquired a 6.0 LQ4 that I am going to put into my 85 Corvette. I'm looking at putting LS3 heads/intake on it and running something like a SNS Torquemax stage 2 cam.

The car is daily driven in the summer time, but driven aggressively. Plans are to run NA for a few years, then add boost down the road. Tear down and re-do bottom end with new rods/pistons so i can run all the boost

Are the AFR Mongoose heads too big for the 6.0 displacement? the 260cc runner has me worried, that's a big *** runner. Will port velocity be total ****? Running a .051 thick gasket would net it around 9.9:1 compression..a little lower than i'd like for an NA build but its the best I can do without tearing into the bottom end, without having the brand new heads milled down to a smaller chamber.

Thoughts/advice?

Thanks!

Jeremy
Pwnage1337 is offline  
Old 10-11-2018, 06:41 PM
  #2  
TECH Junkie
 
Tuskyz28's Avatar
 
Join Date: Sep 2014
Posts: 3,270
Default

Go be alot of opinions on this one...
Tuskyz28 is offline  
Old 10-11-2018, 06:52 PM
  #3  
TECH Addict
iTrader: (2)
 
Join Date: Apr 2006
Location: Pittsburgh
Posts: 2,021
Default

I vote too big
wannafbody is offline  
Old 10-11-2018, 06:53 PM
  #4  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Originally Posted by Tuskyz28 View Post
Go be alot of opinions on this one...
What's yours? Lol
Pwnage1337 is offline  
Old 10-11-2018, 07:01 PM
  #5  
LS1Tech Premium Sponsor
iTrader: (2)
 
Join Date: Apr 2016
Posts: 3,745
Default

Id rather use the tsp 255cc ls heads and their ls3 cams if you are looking for a dyno proven package that works together with a smaller runner.
They machine all their heads in house, design and grind cams in house, and even dyno test them to make sure the customer gets the best lobe/cam design they can especially for their heads.

$3082 gets you heads cam springs and pushrods ready to go.
tech@WS6store is offline  
Old 10-11-2018, 07:11 PM
  #6  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Is 5cc really enough to consider it a "smaller runner" ? Not trying to be a dick bag, just an honest question
Pwnage1337 is offline  
Old 10-11-2018, 07:17 PM
  #7  
TECH Junkie
 
Tuskyz28's Avatar
 
Join Date: Sep 2014
Posts: 3,270
Default

Originally Posted by Pwnage1337 View Post
Is 5cc really enough to consider it a "smaller runner" ? Not trying to be a dick bag, just an honest question
Thats not go be the only differences between the two brands. Take a closer look.... look at the valve angle, valve size etc.

Tuskyz28 is offline  
Old 10-11-2018, 07:22 PM
  #8  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Originally Posted by Tuskyz28 View Post
Thats not go be the only differences between the two brands. Take a closer look.... look at the valve angle, valve size etc.
Will do. Thanks for the help so far guys.

Forgot to add that the car has an 80e with a 3200 stall in it, weighs 3000 lbs.
Pwnage1337 is offline  
Old 10-11-2018, 10:31 PM
  #9  
TECH Fanatic
 
Join Date: Aug 2009
Location: Coast of San Mateo County Between Pacifica & HMB
Posts: 1,440
Default

Even though they physically fit. I vote to big both for the Bore and the displacement.
A tiny cam could make it work.
NAVYBLUE210 is offline  
Old 10-11-2018, 10:46 PM
  #10  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Any recommendations?
Pwnage1337 is offline  
Old 10-11-2018, 10:52 PM
  #11  
TECH Senior Member
 
Join Date: Jun 2016
Location: Central Cal.
Posts: 8,188
Default

Bang for the buck, the LS3 top end will work, but you will lose some low end power compared to cathedral port heads. You don't need anything that will flow more than the LS3 heads, which are good for up to 600HP in stock trim. In your case I wouldn't buy anything more elaborate than the LS3, considering what you can get them for.
G Atsma is online now  
Old 10-11-2018, 11:43 PM
  #12  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Whats the furthest you can cut a 317 head before running into alignment issues? I have the 317's and maybe just better off sending them for port work
Pwnage1337 is offline  
Old 10-12-2018, 12:29 AM
  #13  
TECH Senior Member
 
Join Date: Jun 2016
Location: Central Cal.
Posts: 8,188
Default

I'd worry more about PTV clearance before alignment issues. Of course that also depends on the cam chosen.
G Atsma is online now  
Old 10-12-2018, 07:51 AM
  #14  
TECH Senior Member
iTrader: (2)
 
99 Black Bird T/A's Avatar
 
Join Date: Nov 2001
Posts: 5,777
Default

Originally Posted by Pwnage1337 View Post
I've recently acquired a 6.0 LQ4 that I am going to put into my 85 Corvette. I'm looking at putting LS3 heads/intake on it and running something like a SNS Torquemax stage 2 cam.

The car is daily driven in the summer time, but driven aggressively. Plans are to run NA for a few years, then add boost down the road. Tear down and re-do bottom end with new rods/pistons so i can run all the boost

Are the AFR Mongoose heads too big for the 6.0 displacement? the 260cc runner has me worried, that's a big *** runner. Will port velocity be total ****? Running a .051 thick gasket would net it around 9.9:1 compression..a little lower than i'd like for an NA build but its the best I can do without tearing into the bottom end, without having the brand new heads milled down to a smaller chamber.

Thoughts/advice?

Thanks!

Jeremy
Hi Jersey, given that the plan is to rebuild the bottom end before going to a boosted set up, I would shoot for at least 11.3 to 11.5 compression with the customer set up. When you rebuild the bottom end for boost, you can pick a piston to drop the compression to where you want it. I think that approach will give the best of both NA now and boost later with the same heads.

Given that boost is the end goal, head selection really should factor in how much boost you want to run in my humble opinion. I would be less enthusiastic about a set of 317's or LS3's if big stupid high boost numbers are the plan and favor an aftermarket head with a thicker deck.

If less than 18- 20 pounds of boost is the plan, good tuning, quality build I would probably stick with a GM head to keep cost down.

I would have the heads ported so you can make more power at the same boost level. LS1/LS6/ Trick Flow -TEA (have two sets A+), LS3 Reher-Morrison (two sets) would be top contenders to do my heads. Land Speed, Advanced Induction, Frankenstein, TSP and so on are also top contenders.

I'm this sort of build, (NA, then Boost) I really think Darin Morgan at Reher - Morrison is the correct choice regardless of which head you want to use. Darin will help you get the results you want and keep it on budget because of his exceptional experience and knowledge.

I have several NA LS set ups (TEA & Reher-Morrison) but no LS FI set ups for reference on my level of experience and opinions. Very happy with both as they were outstanding in helping me do what I wanted.

Best wishes with build.

Last edited by 99 Black Bird T/A; 10-12-2018 at 11:10 AM.
99 Black Bird T/A is offline  
Old 10-12-2018, 08:36 AM
  #15  
TECH Fanatic
 
gagliano7's Avatar
 
Join Date: Aug 2005
Location: Monroe,NY
Posts: 1,922
Default

Originally Posted by Pwnage1337 View Post
Whats the furthest you can cut a 317 head before running into alignment issues? I have the 317's and maybe just better off sending them for port work
Advance induction can weld the chambers on the 317 heads so you lower the cc without giving up PTV. If it was me i would get TFS 220 heads touched up by Tooley with powder metal guides so you can use stock rockers. They are the best bang for the buck power wise to me.
gagliano7 is offline  
Old 10-12-2018, 09:57 AM
  #16  
10 Second Club
iTrader: (4)
 
Darth_V8r's Avatar
 
Join Date: Jul 2014
Location: My own internal universe
Posts: 6,387
Default

There are lots of guys who run ls3 heads on a 6.0. Opinions on that combo vary greatly. That said, AFR 260 is going to have better port velocity over a stock ls3 Head (flows more with less runner).

As to it being too big, depends on your intended rpm range. That combo will shine at higher rpm for sure. A 6.0 will need rpm to take advantage of the flow those heads can deliver. If you want to keep rpm down and make good low-mid grunt, keep the cam smallish and let the heads do the work. Great head / mild cam combos are a blast to drive. But in that scenario, you may be better off with a tfs235 for a good all around performer on a 6.0.

One big advantage to jumping to the afr260 will be the ls3 platform has far greater intake options and even the stock ls3 intake is badass.

Personally I like high rpm power and I would run the 260's, set it up for 11.8 compression, cam it in the 230's, and rev the **** out of it, and tune the **** out of it to tame the cam. So I can daily drive it.

Best answer -- be honest with yourself about your goals.
Darth_V8r is offline  
Old 10-12-2018, 11:17 AM
  #17  
TECH Senior Member
 
Join Date: Jun 2016
Location: Central Cal.
Posts: 8,188
Default

Isn't 260 the size of a stock LS3 head intake port? AFR must have changed the basic shape to improve flow as much as they did while keeping the OEM volume
G Atsma is online now  
Old 10-12-2018, 11:49 AM
  #18  
LS1Tech Sponsor
 
TrickFlowTech's Avatar
 
Join Date: Feb 2008
Posts: 297
Default

If you're looking for velocity, our TFS 255's are killer. We give you another .040 in. P to V with our 12 degree valve angle.
__________________
http://www.trickflow.com/emain.asp
Click Above for Product Information
TrickFlowTech is offline  
Old 10-12-2018, 12:41 PM
  #19  
Teching In
Thread Starter
 
Join Date: Sep 2010
Posts: 20
Default

Originally Posted by 99 Black Bird T/A View Post
Hi Jersey, given that the plan is to rebuild the bottom end before going to a boosted set up, I would shoot for at least 11.3 to 11.5 compression with the customer set up. When you rebuild the bottom end for boost, you can pick a piston to drop the compression to where you want it. I think that approach will give the best of both NA now and boost later with the same heads.

Given that boost is the end goal, head selection really should factor in how much boost you want to run in my humble opinion. I would be less enthusiastic about a set of 317's or LS3's if big stupid high boost numbers are the plan and favor an aftermarket head with a thicker deck.

If less than 18- 20 pounds of boost is the plan, good tuning, quality build I would probably stick with a GM head to keep cost down. I would be happy with a car that made 800 whp, on 15-20 lbs of boost. I think its plenty doable, theoretically if the car makes 400 whp, it should be close to 800 whp at 14 psi, right?

I would have the heads ported so you can make more power at the same boost level. LS1/LS6/ Trick Flow -TEA (have two sets A+), LS3 Reher-Morrison (two sets) would be top contenders to do my heads. Land Speed, Advanced Induction, Frankenstein, TSP and so on are also top contenders.

I'm this sort of build, (NA, then Boost) I really think Darin Morgan at Reher - Morrison is the correct choice regardless of which head you want to use. Darin will help you get the results you want and keep it on budget because of his exceptional experience and knowledge.

I have several NA LS set ups (TEA & Reher-Morrison) but no LS FI set ups for reference on my level of experience and opinions. Very happy with both as they were outstanding in helping me do what I wanted.

Best wishes with build.
Originally Posted by Darth_V8r View Post
There are lots of guys who run ls3 heads on a 6.0. Opinions on that combo vary greatly. That said, AFR 260 is going to have better port velocity over a stock ls3 Head (flows more with less runner).

As to it being too big, depends on your intended rpm range. That combo will shine at higher rpm for sure. A 6.0 will need rpm to take advantage of the flow those heads can deliver. If you want to keep rpm down and make good low-mid grunt, keep the cam smallish and let the heads do the work. Great head / mild cam combos are a blast to drive. But in that scenario, you may be better off with a tfs235 for a good all around performer on a 6.0. I'm not afraid of spinning high revs, but given that the car is a daily driver obviously keeping more power in the not 7000 RPM range would be ideal.

One big advantage to jumping to the afr260 will be the ls3 platform has far greater intake options and even the stock ls3 intake is badass. This was part of my thought process as to why going with an LS3 style head vs LS1 cathedral.

Personally I like high rpm power and I would run the 260's, set it up for 11.8 compression, cam it in the 230's, and rev the **** out of it, and tune the **** out of it to tame the cam. So I can daily drive it. Setting up that high of static would drive a pretty high dynamic comp wouldn't it? I just ran a test on Wallace Calcs and a cam with an intake valve closing point of around 70 ABDC @ 11.2:1 static puts the dynamic around 8.4:1 which i think is pretty edgy for 91 pump? We used to have 93 around here but now its gone. I'm not opposed to running E85, but would like to wait until the car is on boost to do it.

Best answer -- be honest with yourself about your goals.
Originally Posted by G Atsma View Post
Isn't 260 the size of a stock LS3 head intake port? AFR must have changed the basic shape to improve flow as much as they did while keeping the OEM volume
I believe so. LS3's are only .2 liters of displacement more, that is why I am so confused as to how roughly 12 cubic inches would make the difference between yes and no

Originally Posted by TrickFlowTech View Post
If you're looking for velocity, our TFS 255's are killer. We give you another .040 in. P to V with our 12 degree valve angle.
I'll check them out, thanks!



Thanks for all the help guys! I'm gonna look at some of the options mentioned here in the thread


Jeremy

Last edited by Pwnage1337; 10-12-2018 at 12:56 PM.
Pwnage1337 is offline  
Old 10-12-2018, 02:29 PM
  #20  
On The Tree
 
Join Date: Aug 2007
Posts: 133
Default

You run the head your engine requires, do the math and then choose a head that flows the cfm you need at the valve lift your using, i bet a trickflow 225 is enough for your engine, superchargers, turbos, nos all will use the same head as n/a, you do not need bigger runners for a forced induction setup. Your 6.0 will never require the airflow those heads supply, it would be a total mismatch imho and you would never use the potential of those heads, plus i bet the airspeed is too slow at low rpm/lift, you would make more power with max ported 243s or Trickflow 225s..... you dont race cfm numbers.

Last edited by SRT8.Acelleration; 10-12-2018 at 02:40 PM.
SRT8.Acelleration is offline  

Thread Tools
Search this Thread

Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: