H/C/I opinions for 398"
01-18-2018, 01:45 PM
#1
Build thread for 393" (Title change) I have the fully forged short block. Looking for H/C/I suggestions/experience.
'Cathedral or Rectangular' (worked by a sponsor), no super high dollar heads, trying to keep semi-budget oriented. (I am currently running ported/milled L92's and stock LS3 intake with a NW92 on a SBE 6.0 and it does pretty good). Just wondering what you guys think would be a better combo for a 398" all out drag set-up, "spinning and spraying the crap out of it".
'Cathedral or Rectangular' (worked by a sponsor), no super high dollar heads, trying to keep semi-budget oriented. (I am currently running ported/milled L92's and stock LS3 intake with a NW92 on a SBE 6.0 and it does pretty good). Just wondering what you guys think would be a better combo for a 398" all out drag set-up, "spinning and spraying the crap out of it".
Last edited by ragtopz28; 10-15-2019 at 02:18 PM. Reason: Thread is old and needs update/name change
01-18-2018, 01:51 PM
#2
If you are on a budget you could consider leaving the heads alone, picking up a FAST 102 intake, and changing your cam to flow more air to use the additional cubes. What compression ratio are you at now and what is your planned compression with your new shortblock?
01-18-2018, 02:05 PM
#3
Goal is to slowly build the 398" on the stand and drop her in when all assembled. Would like to be ~ 11.5:1 compression.
Last edited by ragtopz28; 05-14-2018 at 11:42 AM.
01-18-2018, 02:12 PM
#4
Oh, I thought you were changing the shortblock and wanted options/opinions on what to change with it. Your engine now has ported L92 heads, if you want to flow more you might have to get the high dollar heads you said you didn't want. The FAST102 intake with a matching TB will be worth some good gains. You can get a custom cam ground for your build. Finally, since your block is now forged, you can up your shot. 
What headers and exhaust are you using now?
What headers and exhaust are you using now?
01-18-2018, 02:33 PM
#6
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01-18-2018, 08:24 PM
#9
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In that application absolutely. The Stock ls3 intake runners are tuned for a lower rpm and doesn’t allow you to utilize the rpm you need to really make hp. Where the fast really has no advantage over a Stock intake is on Stock CI with Stock heads and revving in the 6500-6900 range
01-18-2018, 11:04 PM
#10
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Once you have enough cam to Peak at least
7000 RPM & Shift at least 7500 RPM The
Mid Length Runners are Way Beyound the
Factory Intake because of the much shorter
Runner Length as demonstrated by BigHammer's
388", My 396", and SuperHatch's 376".
I would bet our combos made at Least 35 -50+
HP more than a factory LS3 Intake depending on
The size of our cams. SuperHatch even used L92
Heads I believe. Lots of useful data in each of our builds.
01-20-2018, 09:15 PM
#13
Just a slow build until I need to swap into my T/A. No real goals at this point. Maybe 9's on motor. Spin to ~7500. Maybe spray up to 200 through my existing plate. I'm in agreement with the FAST midrunner. Cam selection should probably be last once I have a set goal.
Thanks for all the input so far.
01-26-2018, 09:45 PM
#19
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