Current setup

TMS LQ9, CNC 317s, NNBS intake, 226/232 cam @ 115, 1 3/4 headers, 60e with 3800 stall and 4.10s.

I'm thinking about a change to ls3 heads with the square port truck intake. I know there is a concern with the large intake valve on the ls3 head causing arousing issues but are the gains worth it with a proper spec'd cam?

I'd probably get the GM CNC heads and change the springs.

Thoughts?

 

Just my opinion of course but if you're planning on upping your power then you're better off upgrading the transmission first to handle it. I chewed up three 60es chasing power before I learned my lesson and swapped in the 80e. JMTC.

 

The 60e is built. September was a rough month for me since it was out 2x that month.

It's been fine since.

 

I don't think you'd gain much with the LS3 heads vs your CNC'd 317's

Cathedral head shine down low - LS3's heads are turds down low. If you do go that route you might be able to offset the loss down low with a higher stall converter. Square ports do really well up top.

Do some research to compare your CNC 317's to the GM perf LS3 heads - I remember a while back I did a ton of web searches for dyno charts and comparisons - so I know the info is out there. Then you can make an informed decision.

 

I can't say I think it will be worth a whole ton of HP either honestly. If you were on stock heads that would be another story completely. I dont know much about the TMS heads though. There can be a wide range of performance from one CNC head to another. Could you tell us about them? Valve size? Chamber volume? Runner volume? Did he relay any flow numbers? Flow numbers are next to impossible to compare unless they are literally done back to back... but its data none the less.

 

You should throw on a blower!

Oh, wait...

 

Based on some emails Kyle and I have exchanged they are 69cc, 236cc intake runner (I think). Stock valve sizes.

I've also contemplated a cam change to move from a 115lsa to a 110-112lsa.

Just some ideas I'm throwing around.

 

Meanie.

 

I mean at this point if you are looking for a drastic change in power you either need to make major changes to the drivability of the truck with a looser converter, or you need to go back to FI.

If you wanted to shake things up while staying NA I would say more duration on a narrower LSA would certainly help.

Maybe something closer to a 228/234 112+3
If you were willing to go for serious chop 230/236 111+3

 

That's what I'm thinking. My converter is plenty loose enough to support the 111lsa.

I don't mind the chop. I had a Mustang 3v about 6 yrs ago that sounded like it was chopping trees. Lol


Thanks for the insight.