your intake will be a restriction an you didnt list any cam specs so no real way to give you a idea..even depends on fuel used..if it didnt make 520-550 wheel with that comp an a good cam then id say something is wrong.

 

I don't have my cam specs near me at the moment but I can tell you that it's pretty big. what intake would you suggest?

 

Sounds like Mavn's build on Tech and his Vette...

With No NOS.

 

Your ivc number will determine the intake.i just know the fast even ported is a hinder in a all out deal..if your going to street drive it then the fast will give u nice mid range tq an not make much power past 7k unless you have short or mid length runners in it.. 7k an up stick a hi ram,holley split 4150,4500 super..8k plus use a cid.

 

It'll be interesting to see the power this makes. On paper it should make 500+whp, but I have yet to see a LS3 top end of any kind on a small bore make it on that small of cubes. I am hoping for you, though, I have an LS2 also and the small bore is a bastard to get LS3 port head to work on.

 

I'm really excited to see what it does as well, initially I was gonna go with the f110 cathedral head. After talking to the guys at Frankenstein I was convinced to go with the square port f310. Now I'm ditching the fast and looking into how hard fitting a hi ram will be as well as cutting my hood. I'll be happy if it makes 520-530 through a 4l60 and 3600 stall.

 

The F315 would be a better nitrous head and they offer chamber softening for all their heads which i would highly recommend. The 315 chamber is slower and the exhaust port also flows considerably more as well.

 

I messed up with a Stroker build 4 a 6.0 nitrous thread...

Key is the Compression and Duration @ .050
Turboll and the Softer chamber is on Point and I'm no FI guy.

ER with a 6.2 which is nothing more than a Lq4 as the Hp and Tq Differences would be Minimal...did pretty good although the cam was a S/R it was a Nitrous Build.

500rwhp @ 13+ Compression sounds to Easy depending on How short the can rpm is...

Dave you need to Over think / Out think Steven - Speedtrigger's 402 @ 700 HP if your needing More than 780hp do a Re-sleeve.

any head can have the Intake or Exhaust valves Shrunk... TFS 260 Ls7 heads on a 4.005 x 4.0 stroke? Done? Want the higher Avg power @ 750 + fwhp? 13+ Compression meant for E85 with a Solid roller to 7500 to 7800... Shorter LSA of 108 to 106 would Reel that 7500 in for a tighter Rpm band. How much overlap can one take? Your use of the Vehicle and it's Weight Should determine the Rpm band.

if I see a 418 make a certain Hp @ a given Rpm, my mind is saying it's just a .025 to .070 over Bore.

a bigg Bore block is needed if your Chasing Hp or if you've Got a Boat and rather than Fighting up stream in buying more Tq.

 

The m an f heads i havent seen make anything better then a reg ls3 head. The br3 is what im waiting to see. 4" bore ls3s,4.065 bore or better ls7 or dart/bes 10 degree stuff.

Theres a china ls3 head that fits on a 3.9 bore,think promaxx offers them here..but u can find them an the m311 heads on alibaba

 

The m an f heads i havent seen make anything better then a reg ls3 head. The br3 is what im waiting to see. 4" bore ls3s,4.065 bore or better ls7 or dart/bes 10 degree stuff.

Theres a china ls3 head that fits on a 3.9 bore,think promaxx offers them here..but u can find them an the m311 heads there

This is why I didn't select them for my small cube 370 build. The small bore LS7 stuff seems to kill the LS3 stuff from what I've been reading. The more I talk to head guys and research, I'm beginning to learn that its more about air speed management and port design / shape and less about port size. I see a lot of people get wrapped up in how big the port is and how much it flows and less concerned about HOW it flows.

This is the reason I chose the updated small bore LS7 heads for my build. The engine will reap the benefits of a better port design and better speed / flow characteristics.

 

The Dart 10 degrees heads has been Discontinued....*MBE quote

 

Csa,port speed,flow all matter. The ls3 heads are over valved an on 4.0 bore it hurts them..smaller intake valve an raised floor would be better with them..but the throats like 89% stock. The ls7 is a raised runner version basically..the ls3 is like a failed race head that gm was like shit we can make that work on the street.

 

Basically how it Went ....

 

If you've got the Coin to purchase Ls7 heads cool also a better Head..
But I could live with my Ls3 heads

As factory ported Ls3 heads do Work...as the Dart Ls3 especially and other heads are Basically the same head with benefits. We saw what Steven did with a 402, a 6.0 is just a non Stroker so Tq loss is to be expected. Meaning the Hp is there just @ a higher Rpm which is to be expected using a smaller crank size yet the bore stays the same....ER revv'ed the Ls3 with being bottle fed.

It's all about ones perception...

 

ls1 rec ports..the flow looks fishy but could be a good base to work. XXTREME 240 LS 1/LS2 Rectangle 3.898 Small Bore (SOLD IN PAIRS) - PROMAXX Performance Products

 

Long as the Tunes correct using any power adder one would be ok ...Pick the right intake and fill the cylinder....

Baseline Hp wanted 1st with a power adder as a Bonus....

Compression is 15.1 with a solid Roller but we can Factor in what less compression and a hydraulic roller would lead to... 20 to 25 on Compression and 20 to 25 using a Hydraulic roller same Size duration maybe 30-35 with the lift @ .800 +.....Shorten the cam with a hydraulic. Cylinder Filling makes Alot of Myths possible.

6.0 ls3 head, factory crank, 721hp@8000 e85 - LS1TECH - Camaro and Firebird Forum Discussion

Dynamometer Results & Comparisons - 6.0 ls3 head, factory crank, 721hp@8000 e85 - Recently finished a long running build, aim was 2.0hp per ci and we got there. Still retained factory alloy 6.0, factory crank and ls3 style rectangle heads. Made 721hp@8000rpm and 511ftlb@6800, without vac pump...

ls1tech.com

Reasons I love YB is basic common sense on HP. Some would rather believe or buy a lie...as I don't mind Taking on some as a GROUP on Ls1tech... YB pride of no Lies or BS accepted....

the Best engine builders Reside Here...and there Many, not just one or two who post from time to time and guys get a hard on.

😩😣😖 On a topic of a 15 Hp gain using a solid roller vs a hydraulic
With a 13.x compression 408 with a now purchasing a High Ram + PRC 260 Ls3 heads.
A 10hp difference was shown using a hydraulic LST lobe vs a older Comp cams lobe on a Lesser engine. My thought was What in the hell would a newer Solid roller do vs Either? And dudes doing a Entire top end make over from Factory Ls3 heads and plastic intake.

15hp at the Most was what I was told and I'm willing to bet it was based off of Mamo's 383 LS engine for himself @ under 11.0 compression using a plastic intake and testing a hydraulic roller vs a similar solid roller.

common sense says a larger engine with more compression + a better Line of sight intake would make more Hp and add some lift from .660. 15hp Hp isn't Even common sense its Worship of and not based on facts using a good Comparison @ that.

its the beliefs that get me about the BS and what's being used as a comparison.

rant over...

 

Damn Dave I edited that post to a like .... Hope you still like it and believe I'm correct in my beliefs.