Why do people hate on stock ls3 castings
05-23-2017, 12:43 AM
#261
This is something I wrote on another forum for a guy who bought a 416 w/ CNC ls3 heads for his rock crawler/desert toy. The ls3 intake is rarely swapped out because the fast intake doesn't offer much midrange gain over stock. The intake manifold as you can see with short runner single planes, MSD airforce, and mid runner fast intakes are ultimately important in dictating the power output.
The ls3 head can make great torque and midrange...you just can't also try to make it run to 7k rpm. I think you should cam it for huge torque in the 3500 rpm range - peak at 5500 - and be all done my 6k. People get too aggressive with overlap and kill low end power, but don't have the rest of the system tuned to utilize the high rpm potential of the cam which leads to peaky and lackluster results.
05-23-2017, 01:05 AM
#262
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Originally Posted by big hammer
Would it be possible that people sometimes have bad luck with ls3 castings because they mismatch their overlap and intake harmonics?
05-23-2017, 07:21 AM
#264
For LS3 applications I suspect a fully ported Fast LSXR 102 with medium or short runners would shine with matched cam and deliver excellent gains over a stock LS3 intake IF the engine turns enough rpm. Likewise on a big engine say maybe an aftermarket 500+ LS, the Fast intakes might show gains a lower rpm too
05-23-2017, 10:51 PM
#265
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The nitrous "exhaust port" to my knowledge is actually the same size as the standard exhaust port. The only different to my knowledge is the valve seat angle on the nitrous exhaust port is 50* versus the standard 45*.
This decreases flow from .100-.300 lift, catches back up by .400 and increases significantly past .500 lift.
This decreases flow from .100-.300 lift, catches back up by .400 and increases significantly past .500 lift.
Larger ~5CCs, valve job is a little different as mentioned as well.
I do not know for sure, but I think some other
Nitrous exhaust Ports are larger for some other heads as well.
05-24-2017, 03:21 AM
#266
Quick question kinda off topic, with Ls3 heads and a Super Vic would a spacer help any with a 4500 T/b. Looking at a number of spacers and really have never seen one used with a T/b. Looking at a few tapered spacers, they say they help increase air flow this is from Wilson. Just never seen one used myself with a T/b and I've looked everywhere.
The BIG ONE from Wilson, is on a 4500 flange bolt pattern, and capable of accurately flowing 2,320 cfm. These throttle bodies are designed to also work in concert with Wilson’s carb spacers, and with one of the company’s 1.5-inch tapered spacers, that figure grows by 160 cfm
05-24-2017, 09:48 AM
#267
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https://ls1tech.com/forums/generatio...b-spacers.html
Everything you need to know about throttle body spacers right here. Lol
Everything you need to know about throttle body spacers right here. Lol
05-24-2017, 07:46 PM
#269
Yeap had me lmao. Sounds like the intake charge was faster yet that's with a 90mm t/b and a Fast intake small ball in comparison. But thanks anyway. I'll get a hold of Mr. G. Klass and call Wilson before Memorial day hopefully...to many 12 hr shifts a day no time to call or talk. It's too dangerous to call at work for myself and others working with me.
05-25-2017, 06:27 PM
#271
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Originally Posted by Patron
Darth from what Mr. Klass told me it's a Non factor a spacer is only good for linkage clearance.
I liked what hammer said in his thread. It successfully moved the throttle body away from the manifold the exact same distance as the thickness of the spare
05-26-2017, 07:28 AM
#272
05-26-2017, 07:56 AM
#274
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The problem with that test isn't so much the cam as it is your never gonna reach the potential of the ls7 head with a fast intake.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
Last edited by HioSSilver; 05-26-2017 at 08:09 AM.
05-26-2017, 08:16 AM
#275
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The problem with that test isn't so much the cam as it is your never gonna reach the potential of the ls7 head with a fast intake.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
05-26-2017, 09:36 AM
#276
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05-26-2017, 10:25 AM
#278
The problem with that test isn't so much the cam as it is your never gonna reach the potential of the ls7 head with a fast intake.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
They also need to stop ***** footing these tests around the 6x00 rpm era and let us see what happens over the curve a bit. No reason these engines can't run to 7k+
If i were building a 400+ ci engine fir my truck....cathedrals all the way. Let her down shift and pull in the 3k rpm to 4krpm range. If I'm racing my car and I'm dumb enough to let it be at 3k-4k rpm I've already lost.
05-26-2017, 10:41 AM
#279
And this for tfs 260's and getting 400+ cfm just needs short side work and a good valve job.
http://www.yellowbullet.com/forum/sh....php?t=1018978
I'll take the Ls7's with a carb intake and a Solid roller with lift over 750 + please and that will be it for my order. No soft drink. Oh I would also like a car under or @ 3000 lbs and that's it. Rpm is needed to go Fast with the higher ups and Not TQ. RPM is Hp.
Let me get my as up and go pay for having this 2002 Chevy 2500 engine and trans removed. I'll keep both ecu's and harness. Anyone needing 6.0 internals and heads with intake I'm keeping the block and all accessories. Complete truck for 300 bucks so Funny. I'll get that back just going over the scale. LMAO!
http://www.yellowbullet.com/forum/sh....php?t=1018978
I'll take the Ls7's with a carb intake and a Solid roller with lift over 750 + please and that will be it for my order. No soft drink. Oh I would also like a car under or @ 3000 lbs and that's it. Rpm is needed to go Fast with the higher ups and Not TQ. RPM is Hp.
Let me get my as up and go pay for having this 2002 Chevy 2500 engine and trans removed. I'll keep both ecu's and harness. Anyone needing 6.0 internals and heads with intake I'm keeping the block and all accessories. Complete truck for 300 bucks so Funny. I'll get that back just going over the scale. LMAO!
Last edited by Patron; 05-26-2017 at 10:56 AM.
05-26-2017, 11:48 AM
#280
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Referring to the 427ci head test.... I'm willing to be bet if Richard wouldve swapped the ls7 spec cam out for a cathedral spec camshaft the 245s would had made the same exact horsepower number as the larger LS7 head or maybe 5-10 horses more.
It still surprised the hell out of me seeing the 245 tfs cathedral make 600 ftlbs on a 427ci with a mismatched cam and was only 10 horses behind at the tfs ls7 head at the top of the powerband.
That TFS 245 head is just badass!!
Patron, you speaking on the short side radius on the LS7 head...hmmm I wonder what would happen if you did the short side radius to the LS7 heads vs a nitrous exhaust port job on the the tfs 245 heads?
It still surprised the hell out of me seeing the 245 tfs cathedral make 600 ftlbs on a 427ci with a mismatched cam and was only 10 horses behind at the tfs ls7 head at the top of the powerband.
That TFS 245 head is just badass!!
Patron, you speaking on the short side radius on the LS7 head...hmmm I wonder what would happen if you did the short side radius to the LS7 heads vs a nitrous exhaust port job on the the tfs 245 heads?