How would the engine run if the pushrods were too long?
06-02-2005, 03:46 AM
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How would the engine run if the pushrods were too long? Just as the title says! Lets say running 7.4's instead of 7.35 pushrods.
Would it run?
If it did run, would you see anything odd in the A/F ratio?
Would the valves make less noise?
If anyone has done this can you tell me about you experience please?
Would it run?
If it did run, would you see anything odd in the A/F ratio?
Would the valves make less noise?
If anyone has done this can you tell me about you experience please?
06-02-2005, 07:21 AM
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I have tried both on the same motor setup and there wasn't a difference. This is with stock lifters. Now if you go with Comp R lifters then the preload will be out of spec.
06-02-2005, 07:22 AM
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According to Comp, too much lifter preload can cause low manifold vaccum and a rough idle.
You should actually measure the preload to see exactly where you're at. If you're running factory lifters you need around .060(+/- .020) preload. Comp stocks PR's in .025 increments now so it shouldn't be difficult to get the correct length PR.
You should actually measure the preload to see exactly where you're at. If you're running factory lifters you need around .060(+/- .020) preload. Comp stocks PR's in .025 increments now so it shouldn't be difficult to get the correct length PR.
06-24-2005, 09:04 PM
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i put longer pushrods in mine after installing new rockers and the car wouldnt start at all.longer pushrods were actually pushing the valve down and keeping it open so there was absolutely no compression for the engine to fire.
06-24-2005, 09:54 PM
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It can range from not running at all, to not wanting to start (sputter, then stall), to just running rough at high RPMs. Depends on how badly they hang the valves open.
