Advanced Induction 243 CNC port gains 49HP/32TQ and 5 tenths/5mph
#42
10 Second Club
iTrader: (10)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
If you can get the CR past 10.5:1 to 11.1:1 or a little higher that smaller cam that you have will have some nice cylinder filling at lower rpm since your cam doesn't have crazy duration. Even with the bigger intake port on your 5.3 I don't think it would hurt your low end or mid range much at all in fact it should pick up a lot in the mid range and may even gain a tad in the low end as long as the CR stays at 11.1:1. So thinner head gasket, milling the heads down, and zero decking your engine would be enough IMO to use the 227cc intake port that these CNC 243's have. Again this will likely be possible due to your cam only having 218/222 degrees of duration, but you will definately want to check ptvc clearance before firing it up.
#43
11 Second Club
iTrader: (15)
Join Date: Mar 2007
Location: So Cal
Posts: 772
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Curious what kind of gains I could get over my Gen 1 PRC Stage 1 243's (before they revamped there cnc. 304cfm @ .600 and fell off hard above .600). I was looking to get a set of TEA or AI's 243's. Mods in sig.
#44
10 Second Club
iTrader: (1)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The results are nice. I gained 5 tenths from afr out of the box 205 heads years ago. and that was over a top sponsors cc ported ls1 heads. More options for people on buying heads. real nice and the track backs it up too.
Last edited by mike c.; 07-26-2011 at 08:51 PM.
#47
#50
MASS seller approved
iTrader: (148)
Join Date: Jul 2007
Location: ELSA, South TEXAS (956) 802-7700
Posts: 1,426
Received 133 Likes
on
89 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)
#56
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Thanks! ![Cheers!!](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cheers.gif)
I have been through SEVERAL sets of heads in my wrenching life. My experience is that sub-3000rpm, part-throttle, tip-in suffer from "over-sized" intake runners. They of course will punch out a big peak HP, but I actually drive my cars and I am unwilling to throw away sub-3000rpm performance... I am not so much concerned if these heads actually made more power than the previous heads below 3000rpm, BUT that they did no lose power in that range by comparison.
BTW, I am not saying these heads suffer from the above. I am looking for more results and clarification...
![Cheers!!](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cheers.gif)
I have been through SEVERAL sets of heads in my wrenching life. My experience is that sub-3000rpm, part-throttle, tip-in suffer from "over-sized" intake runners. They of course will punch out a big peak HP, but I actually drive my cars and I am unwilling to throw away sub-3000rpm performance... I am not so much concerned if these heads actually made more power than the previous heads below 3000rpm, BUT that they did no lose power in that range by comparison.
BTW, I am not saying these heads suffer from the above. I am looking for more results and clarification...
#58
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Does the guy still own that car?
Thanks!
I have been through SEVERAL sets of heads in my wrenching life. My experience is that sub-3000rpm, part-throttle, tip-in suffer from "over-sized" intake runners. They of course will punch out a big peak HP, but I actually drive my cars and I am unwilling to throw away sub-3000rpm performance... I am not so much concerned if these heads actually made more power than the previous heads below 3000rpm, BUT that they did no lose power in that range by comparison.
BTW, I am not saying these heads suffer from the above. I am looking for more results and clarification...
I have been through SEVERAL sets of heads in my wrenching life. My experience is that sub-3000rpm, part-throttle, tip-in suffer from "over-sized" intake runners. They of course will punch out a big peak HP, but I actually drive my cars and I am unwilling to throw away sub-3000rpm performance... I am not so much concerned if these heads actually made more power than the previous heads below 3000rpm, BUT that they did no lose power in that range by comparison.
BTW, I am not saying these heads suffer from the above. I am looking for more results and clarification...
I can't wait to see what these heads do with a ms3 cam on a 383.
#59
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Yep. The short block is getting tired tho. We're in talks of doing a 408ci in the very near future.
I can assure you A.I.'s programs make more power everywhere. Phil is a firm believer (as am I) that moving air fast, is more important than winning flow bench races on the internet. That's why almost all of his CNC programs for GM castings use the stock valves. Bigger valves can hurt low end, they're not necessary, and plenty of power can be had with a stock valve.
I'll let you know soon. I just built a 383 that's been installed in a GTO, that will be getting A.I. ported 243's in the near future. For now it's got a Spartan 228/236 and stock 243's, so we'll have another good back/back comparison.
I can assure you A.I.'s programs make more power everywhere. Phil is a firm believer (as am I) that moving air fast, is more important than winning flow bench races on the internet. That's why almost all of his CNC programs for GM castings use the stock valves. Bigger valves can hurt low end, they're not necessary, and plenty of power can be had with a stock valve.
I'll let you know soon. I just built a 383 that's been installed in a GTO, that will be getting A.I. ported 243's in the near future. For now it's got a Spartan 228/236 and stock 243's, so we'll have another good back/back comparison.