Why aren't 396 LS1 Strokers popular?
#41
Originally Posted by VINCE
Kumar I just read a earlier post. You are running a 244/250 with .630 lift cam. What LSA? No wonder your car peaks so high for that 4.125. That's why I said it depends on the cam..
I will post some dynos after I get car back from its updates.
#43
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Originally Posted by Mike K.
That is awesome for that cam size. I bet your setup is streetable as hell also which is awesome.
I'm thinking about bumping it up to a bigger cam, but will most likely wait until some of the new items come out & see how they pan out.
#44
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Originally Posted by kumar75150
Its on a 114 lsa. The cam is big compared to what some people run but if you think about the new Thunder cam on a 346, mine is comparatively small. The car takes about 5 seconds to find idle and driveability is fine.
I will post some dynos after I get car back from its updates.
I will post some dynos after I get car back from its updates.
#45
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I also agree --a lot of the kits avail are too under square --the best way imo is a 388 all bore -ive seen 510 come out of some of those --I guess it all comes down to balanceing
#46
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Originally Posted by Nine Ball
Oversquare engines tend to rev quicker than undersquare engines also.
Tony
Tony
#48
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As far I understand, between the boring or stroking is the following:
When you bore an engine, the engine tend to make more Hp, which mean you make HP > TQ, and usually the HP peak's in the higher range of RPM...And this is why road racing engine is bored to make use of the HP at a higher RPM (from 5000 RPM ~ 9000 RPM)
When you stroke an engine, the engine tend to make more TQ, which mean you make TQ = HP or TQ > HP, and usually the TQ peak's in a lower range of RPM (From 3000 RPM ~ 4500 RPM)...and this is why street racing enigne can benifit from that case, where in the street racing you need TQ that make the car jump from the ground to fly...
Thanks...
When you bore an engine, the engine tend to make more Hp, which mean you make HP > TQ, and usually the HP peak's in the higher range of RPM...And this is why road racing engine is bored to make use of the HP at a higher RPM (from 5000 RPM ~ 9000 RPM)
When you stroke an engine, the engine tend to make more TQ, which mean you make TQ = HP or TQ > HP, and usually the TQ peak's in a lower range of RPM (From 3000 RPM ~ 4500 RPM)...and this is why street racing enigne can benifit from that case, where in the street racing you need TQ that make the car jump from the ground to fly...
Thanks...
#49
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Originally Posted by LS6
As far I understand, between the boring or stroking is the following:
When you bore an engine, the engine tend to make more Hp, which mean you make HP > TQ, and usually the HP peak's in the higher range of RPM...And this is why road racing engine is bored to make use of the HP at a higher RPM (from 5000 RPM ~ 9000 RPM)
When you stroke an engine, the engine tend to make more TQ, which mean you make TQ = HP or TQ > HP, and usually the TQ peak's in a lower range of RPM (From 3000 RPM ~ 4500 RPM)...and this is why street racing enigne can benifit from that case, where in the street racing you need TQ that make the car jump from the ground to fly...
Thanks...
When you bore an engine, the engine tend to make more Hp, which mean you make HP > TQ, and usually the HP peak's in the higher range of RPM...And this is why road racing engine is bored to make use of the HP at a higher RPM (from 5000 RPM ~ 9000 RPM)
When you stroke an engine, the engine tend to make more TQ, which mean you make TQ = HP or TQ > HP, and usually the TQ peak's in a lower range of RPM (From 3000 RPM ~ 4500 RPM)...and this is why street racing enigne can benifit from that case, where in the street racing you need TQ that make the car jump from the ground to fly...
Thanks...
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For a given size engine (call it a 388), the stroked motor will have more area under the curve and will generally peak lower in the RPM range (if cam/heads are the same for each motor). The all-bore motor will likely make a few more HP at (a higher) peak.
As for RPM levels for a given stroke, remember that there are plenty of other motors out there besides LS1's... for instance, the 5.4L Fords have a stroke of something like 4.15" (though they have that pathetically small bore at ~3.54") and in proper trim they can be wound out just fine. On the Chevy side, look at the 454 BBC... 4.25" bore, 4.00" stroke. 7500 RPM for a built 454 isn't unheard of, so it isn't like it can't be done (consider also, though, that the 454 is going to have a higher piston/rod weight and a taller deck height... the higher piston/rod weight of the 454 would give it a disadvantage compared to a 4" stroke LS1, but the taller deck height is going to allow for more advantageous pin placement).
As for RPM levels for a given stroke, remember that there are plenty of other motors out there besides LS1's... for instance, the 5.4L Fords have a stroke of something like 4.15" (though they have that pathetically small bore at ~3.54") and in proper trim they can be wound out just fine. On the Chevy side, look at the 454 BBC... 4.25" bore, 4.00" stroke. 7500 RPM for a built 454 isn't unheard of, so it isn't like it can't be done (consider also, though, that the 454 is going to have a higher piston/rod weight and a taller deck height... the higher piston/rod weight of the 454 would give it a disadvantage compared to a 4" stroke LS1, but the taller deck height is going to allow for more advantageous pin placement).
#51
Think about critical piston speed.
Two engines:
3.62 stroke x 4 inch bore
4 inch stroke x 3.905 bore.
The 4 inch stroke motor will reach critical piston speed earlier, thereby theorectically limiting its rpm potential. Stronger rods, rod bolts etc can help increase critical piston speed rpm.
With a street motor that runs under 7200rpm this is a non-issue for the most part. As you go higher in the rev range this becomes much more of a factor. Again oiling is the big concern with these motors at high rpm and well as spring/lifter issues.
Cheers,
Chris
Two engines:
3.62 stroke x 4 inch bore
4 inch stroke x 3.905 bore.
The 4 inch stroke motor will reach critical piston speed earlier, thereby theorectically limiting its rpm potential. Stronger rods, rod bolts etc can help increase critical piston speed rpm.
With a street motor that runs under 7200rpm this is a non-issue for the most part. As you go higher in the rev range this becomes much more of a factor. Again oiling is the big concern with these motors at high rpm and well as spring/lifter issues.
Cheers,
Chris
#56
Originally Posted by DaveSchott
remember most ss396's were actually 402's! put whatever badges on it and have fun, who'll know?
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I just want to understand about the subject of oil consumbsion in the stroked engine, where I don't have any experence at all about it...How it lead to eat oil in stroked engine than a bored engine...
I heard about the ford truck that is 5.4L and stroked but doesn't have any oil issue...
Also, as far as I know the stroked engine from the BMW on the M3 is very powerfull but I didn't hear any oil problem issue...
Could some one elaborate more on this subject for the sake of knowlage...
Thanks...
I heard about the ford truck that is 5.4L and stroked but doesn't have any oil issue...
Also, as far as I know the stroked engine from the BMW on the M3 is very powerfull but I didn't hear any oil problem issue...
Could some one elaborate more on this subject for the sake of knowlage...
Thanks...
Last edited by LS6; 02-17-2004 at 03:19 PM.