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| Building the Ultimate 2.8L (Page 3/9) |
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DarcyJL
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MAR 24, 03:08 PM
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No not alot at all...i may be disregarding the ti valves not sure yet though.
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Arns85GT
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MAR 24, 05:38 PM
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| quote | Originally posted by zkhennings:
You cant use 1.6 rockers with 260 cam and factory springs, you will get crazy valve float. |
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Sorry, I have to disagree. I have been running 1.6 roller tips with stock springs on the stock cam for 8 years now and there is absolutely no valve float and absolutely no premature wear, or any wear at all. The 260 will be just fine with 1.6 but, I do agree that better springs are not a bad idea.
Arn
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Jeff Young
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MAR 24, 05:49 PM
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| quote | Originally posted by Arns85GT:
Sorry, I have to disagree. I have been running 1.6 roller tips with stock springs on the stock cam for 8 years now and there is absolutely no valve float and absolutely no premature wear, or any wear at all. The 260 will be just fine with 1.6 but, I do agree that better springs are not a bad idea.
Arn |
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but at what rpm?
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hiwil88formula
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MAR 24, 06:57 PM
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i just recently did my 3.4 swap and used the 260 cam with 1.6 roller tip rockers. At the advice of my machine shop i did not replace the factory valve springs. At idle its fine, but under load about 3500 RPM i get valve float. so now i have to change out the springs to the correct ones. I like the 260 cam with those rockers though, it gives it a nice lopey sound.
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Arns85GT
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MAR 24, 08:21 PM
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| quote | Originally posted by Jeff Young:
but at what rpm? |
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With the stock cam (which is close to the 260) I have revved clean to 6200 rpm with no float. But, like I said above, the heavier springs are still a good idea.
Arn
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uhlanstan
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MAR 24, 08:58 PM
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Truelo is no longer making his headers ,so watch for a used set,no other modification will bring the benefits of the dyno proven Truelo headers ,only a great porting job is superior to great headers they do not stress an engine .
I recomend the Dyno max "super turbo" muffler it gives a real increase in power & fits in the stock location barely,use hard ware store L brackets & turnbuckles to mount your muffler
the next best is the borla if you want to use GT twin exhaust tip exits
use DYNOMAX #17730
if you go over 150 hp at rear wheels you may want to go to larger exhaust pipes(3in) & a larger muffler
never mount a muffler where the Catylictic converter was,, this hurts performance,you want the mufller as far back as possible.
any engine over 175 hp needs dual exhaust,,,you want the pipes as long as possible
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ericjon262
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MAR 24, 10:33 PM
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zkhennings
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MAR 25, 01:55 AM
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I have heard of people getting valve float above 6000 with the stock cam and rockers but I am not doubting you, I just know that it happens... And the 260H cam (at least the comp cams cam) Has equal intake and exhaust duration. This is good for a turbo application, but you want a longer exhaust duration with a NA motor so I reccomend a custom grind as well.
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Arns85GT
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MAR 25, 08:20 AM
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The guys you've heard of with valve float over 6000 are most likely guys with tired valve springs, or improperly adjusted rockers.
I can tell you that my engine, with the 1.6 and stock cam has been dyno'd at 132 hp at the wheels. It was still pulling hard at 6200 rpm and I believe it can rev to 7000 but I don't have the gonads for it.
The Cloyes roller timing set is a good idea. Any improvement on the oil passages is good. The stock oil pump works just fine. I also have reservations about the Falconer heads. You really do need to check their volumetric capacity.
If you want it stock looking, you probably want to use the shorty headers. I have proper long tube headers, but, they are definitely not stock in any way. But they do give the engine a nice kick, and I did not have them when the car was dyno'd, so my rw hp is likely closer to 140 right now.
There are other things which accumulate your usable power. You might want a WOT Tech crank scraper. That keeps your oil in the sump where the pump can get at it at high speeds. You might want the power pulley and Rodney's idler pulley setup.
Arn
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2.5
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MAR 25, 09:24 AM
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Motor only, or turbo or nitrus ok?
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