xc_SS/RS

i've got one made by a friend and he used 3/8" rods

edit: how did you remove the center posts at the top? i've been tempted to try this on my old intake manifold

Johnny_M

Yep. JB original is what JB suggested when I called them. I'm ok with JB. I've used it in the on Cylinder heads and it held up.

Johnny_M

I used a hack saw blade on my air saw. It danced around but I didn't cut into a runner

Johnny_M

I got the rod mod done

cam

iTrader: (9)

Looks good

What did you do to locate the holes in the rear of the intake? Did you JB weld over the rods? Got pics of the back there?

Johnny_M

I used the 1/2" rod with a point ground on it to go through the front to mark the back.
Then I drilled part way through with a "through wall" drill bit. Then I drilled outside from the back with a 1/2" step drill bit.
Installed the rods and JB'd it.

xc_SS/RS

Did anyone ever flow test a LS3 intake manifold with porting, radius rods, and a 102mm+ throttle body? Curious if adding a larger throttle body and having the inlet port matched would be a benefit. I'm eyeing the granatelli 103mm tb right now since TSP still doesn't have their 105mm one for sale yet

Also thread resurrection.

Johnny_M

I haven't but here is a video of Gwatney at Kunze & Co. testing several LS3 intakes.

Johnny_M

depending on your h.p., cubic inches, transmission type. Weight of the car, etc. You can hurt the low end torque if you go too big of a t.b. I stayed with a 92mm on my 408 LS3 with CNC ported heads. I did pick up .24 in The quarter mile switching from my Rod mod with the stands removed ls3 intake to a F.A.S.T. 102mm with hp runners

xc_SS/RS

That's what I'm worried about. I'm wondering if the stock TB is "small" at 90mm to help increase air velocity into the manifold

The engine is a bolt on LS3 in a fatgen. Stock cam so nothing crazy. Just looking to mess with stuff lol but if this might hurt things then I'll skip it and stay with a ported TB

Johnny_M

I would stay where you're at with the stock tb. You will lose velocity down low on a stock cam engine

xc_SS/RS

So I had HioSSilver port my rodmod intake manifold to accept a NW102 and it feels like it gained a little bit in the midrange. Very happy with it and it was easy to adjust the tune for the larger throttle body. I do have clamps on the intake hose lol

99 Black Bird T/A

iTrader: (4)

That 102 LS3 radius rod mod intake looks pretty trick! Would be really sweet to see a before and after dyno or flow test.

What are you using to seal the TB to the intake? Permatex gasket maker?

spanks13

iTrader: (5)

That’s dope! I’ve seen many people say it can’t be done.

Is that the Texas speed 102, or the eBay one?

How do you like it?

I’ve had a GPI rod mod intake for a good while but it was before they offered the porting. I never felt like it did a lot. The porting has always been on my mind and now you added the 102 to the mix haha

xc_SS/RS

Thanks! I’m using a paper gasket. Hio filled in all of the voids on the front with epoxy to give more surface for the gasket to connect with

I really need to get it on a dyno to see what it makes. Never had it on one before and now I’m very curious. Per my HPT logs I think it’s flowing more air at peak torque (4-5 g/s more) and it seems to get to peak airflow (350 g/s-ish) sooner which makes sense to me. Engine can’t utilize more airflow at peak HP (stock cam) but it looks like it wanted more at peak TQ

Thanks! It is a Nick Williams 102 and I really like it. I’ve seen three other users with a 102 Tb on the stock LS3 intake manifold so I was a little anxious but it works lol

The porting seems to really make a difference. I think GPI tested a rod mod vs a ported rod mod and the ported one came out on top. When logging with HPTuners it looks like around peak torque it’s moving 4-5 g/s more air now with the 102 (vs 90 Tb) and the Engine Torque PID says it gained 8-10 ft lbs at peak torque but I don’t really believe it’s that much of a gain lol

Corona

Normal guy Ls3 porting and testing. 7500+ Capability

https://www.yellowbullet.com/threads...ntake.2584115/

Johnnystock

iTrader: (6)

I asked my man to make me one like this. I will be testing against a short runners sheemetal intake in spring, solid roller sbe LS3. I think this tricked-out LS3 intake deserves a lot more attention.

LaBLKv6Z

iTrader: (13)

It looks similar to an LS7 intake plenum.

xc_SS/RS

The rod-mod is a good modification but I don’t know if people have gotten more performance by cutting the runners back. I know two guys did it on Camaro5 and one said there were no gains on his SBE set up and the other I think mentioned gains but I don’t remember what they were

In for the results!

Corona

Old news. 7000+ not 7500+. Maybe they didn't Know what they were doing on porting🤔👍

my buddy Suicidal's post :
guess ill show my ls3 intake i did..i opened it up to a 102mm tb size vs stock 90mm..i then cut the runners back from 9.5" to 7.5" in hope to get it to carry power better,smoothed an radiused all port entrys.

intern it was worth 15hp over a stocker from 6600-7000..it seemed like it flat lined an held though an dropped rapidly after 7200..not sure why or what made it do this..im sure one of you guys with more experience would know..with a holley split single plane intake an elbow combo.the test engine peaked 6900 an made 600hp.





dyno results for ported ls3



stock ls3 intake did 570hp @ 6600
Tony laino
/threads/carb-and-intake-show-and-tell.214422/post-72640714