TFS 245 vs. TFS 260
03-15-2019, 08:40 AM
#162
10 Second Club
Not to be picky but based on the SAM 436ci combo everything is the same as my engine except the block, bore size, crank, rod type, rod length, pistons, ring set, heads, intake, throttle body, cam type, cam size, pushrods, compression, oiling system, ignition, header style and header size.
03-15-2019, 10:44 AM
#164
TECH Senior Member
The only time I EVER give advice about high revving NA street engines is AFTER they blow. Then I say, "Well, I guess you shouldn't have done that..." at a safe distance....
03-15-2019, 10:57 AM
#165
I may not know camming but do know where a given duration @ .050 places a engine as far as stroke for a given rpm. For a SR cam mid 250's to 260 gives you a rpm peak of around 7500 with a 4 in arm. Some go over 260 @ .050 and limit rpm with a tighter lsa. Same basic idea used for the thought of a 900 fwhp street engine (btw 7800 to 8000 rpm & higher compression with a engine this size or larger ). I believe i've got 700- 800+ covered with less than 416 ci. There are some basic builds that tell you. But old build threads just need a update with modern parts and ideas. For this build all i'd change is cam and intake. Lower lift and instead of the sheet metal intake a Holley ram or CID on e85. Ask Darth for a modern take on the cam. Nothing special. I've asked could this be done for the street and the answer is yeah. 800 is old news.
https://ls1tech.com/forums/dynamomet...e-dyno-na.html
https://ls1tech.com/forums/dynamomet...e-dyno-na.html
03-15-2019, 10:58 AM
#166
Not the guys that are winning. That Gen 3 Hemi that kicked everyones *** was the smallest port from the factory, and they still put a bunch of epoxy in it to make it even smaller, despite the shortblock being about 60ci bigger than what those heads were designed for.
03-15-2019, 11:09 AM
#167
KCS George Bryce broke it down this way so it's easier to concept. Bro just look at a gen V lt1 head. 320 cc for a .065 bore using a 2.120 valve. Asked about using them on a Ls can work with it's higher runner placement and better valve angles. Direct injection Must be welded up & DI isn't great for Rpm and NA applications. Steve @ RED on if it will work and Darin on DI use for NA. Just a curious guy.
Ls not a hemi, different head architecture
Ls not a hemi, different head architecture
03-15-2019, 11:26 AM
#168
KCS George Bryce broke it down this way so it's easier to concept. Bro just look at a gen V lt1 head. 320 cc for a .065 bore using a 2.120 valve. Asked about using them on a Ls can work with it's higher runner placement and better valve angles. Direct injection Must be welded up & DI isn't great for Rpm and NA applications. Steve @ RED on if it will work and Darin on DI use for NA. Just a curious guy.
03-15-2019, 11:43 AM
#169
Pretend to be buddies? If there on my phone and have there cell number and any question is answered what is this called...Good guy's. Btw a hemi again is not a Ls different layout. Look at any Ls builds for the emc from: BES,SAM,Shaver Specialty, RED, AMS with a Ls7 head larger ports used. Hemi heads don't fit but do know a guy who knows a guy who makes and sells Ls hemi heads. Also a cast intake was used and not a fast nor msd intake for a peak rpm of 6500 to 7500. Sam Ls7 heads are what, around 3.2 mcsa for the EMC those BES heads around 3.0 closer to 3.1? Curiosity..
Last edited by Smokey B; 03-15-2019 at 12:00 PM.
03-15-2019, 01:19 PM
#170
I’m building a 428 and am going to use a 254 or 258 intake lobe and 285cc ls7 heads shooting for a 7300-7500 rpm peak. Wide centers probably 116+2 I think with a 276 exhaust lobe. New low shock solid roller profile from comp.
Holley sniper is going on for a 5500-7800 racing range, and yes it’s something I’ll drive a lot on the street.
12-12.5:1.
I want to keep peak torque low, but have it carry to 8000 rpm as I’m quite traction limited even at 450rwtq right now.
Unsure how much power I’ll make with this thing, but I’d be happy with 730fwhp. I think there’s potential for it to make more, but I’ve yet to see results like that anywhere but the internet.
Holley sniper is going on for a 5500-7800 racing range, and yes it’s something I’ll drive a lot on the street.
12-12.5:1.
I want to keep peak torque low, but have it carry to 8000 rpm as I’m quite traction limited even at 450rwtq right now.
Unsure how much power I’ll make with this thing, but I’d be happy with 730fwhp. I think there’s potential for it to make more, but I’ve yet to see results like that anywhere but the internet.
03-15-2019, 01:51 PM
#171
Sounds like John's build just make sure to keep weight down on the valve train with larger valves. Bigger push rods being used. The more intake potential the more hp that's available. Reason why a larger carb or tb will generally make more power
03-15-2019, 01:57 PM
#172
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Be surprised if you do not hit 730 flywheel honestly.
03-15-2019, 03:36 PM
#174
Valves are Ti intake and stainless exhaust.
Predictability of the power delivery is really what I'm looking for. I'd like as flat of a torque curve as possible that carries as high as possible. Smooth and consistent power up to redline, and something that will pull 5th gear to 7800rpm @ 200 mph without running out of steam. It is important to me for the engine to still be maintaining or building power at maximum rpm.
The only thing that keeps me up at night is if I'm going to overshoot the horsepower peak on accident and wind up with an engine that wants to peak at 8000 rpm. Second worry is that it won't have enough ***** at ~5600 rpm to pull away from the gear changes.
Predictability of the power delivery is really what I'm looking for. I'd like as flat of a torque curve as possible that carries as high as possible. Smooth and consistent power up to redline, and something that will pull 5th gear to 7800rpm @ 200 mph without running out of steam. It is important to me for the engine to still be maintaining or building power at maximum rpm.
The only thing that keeps me up at night is if I'm going to overshoot the horsepower peak on accident and wind up with an engine that wants to peak at 8000 rpm. Second worry is that it won't have enough ***** at ~5600 rpm to pull away from the gear changes.
03-15-2019, 04:24 PM
#175
Let me get home and maybe Darth and myself can give you a basic idea of where your at with a given duration with a 4 inch crank. We have many references and Steven from cam motion or Speedtrigger can give a exact number. 258 is around 7500. 256 I had with a 112+4 and 730 lift was a 7400 7500 cam. Moved the duration 4 points to 260 on a regrind. Let me get home and we can see
03-15-2019, 05:34 PM
#177
03-15-2019, 05:51 PM
#178
Good thread. What intakes are guys using on the 434ci LSX setups that run direct port 300 shots? Yes I will search but I see quite a few in here that will know off the top of their head so figured I'd ask. I'll probably go with Tony for the heads.
Last edited by 5.7stroker; 03-15-2019 at 05:59 PM.
03-15-2019, 06:05 PM
#179
You'd need to get with a porter and discuss chambers and a 300 shot of drugs. BES or C. Frank off the top of my head and a Mast,all pro, now the big spring brodix head my fav 4 cost. If you know of Dennis Wheat GREAT head porter and person. CID 4500 intake with a accufab 5500 or 6500 Tb port matched top end.