RR to tight, loss of power?
04-27-2007, 11:15 AM
#1
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RR to tight, loss of power?
When I first did the H/C there was a bit of valvetrain noise. I had everything at half turn, a buddy of mine told me to go back through them and adjust as needed. So went back and gave a 1/4 turn more.
The car feels down on power, and just wondering if this is why I put down horrible numbers the other day ( 264/293 ). It doesnt feel nearly as tourqey anymore.
What do you guys think?
The car feels down on power, and just wondering if this is why I put down horrible numbers the other day ( 264/293 ). It doesnt feel nearly as tourqey anymore.
What do you guys think?
04-27-2007, 11:17 AM
#2
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What rockers, springs, lifters? Even if its all stock that sounds a little on the tight side. I ran stock lifters with comp 1.6 rockers @ 1/4 turn past 0.
I think its easier to adjust them with the car running.
I think its easier to adjust them with the car running.
04-27-2007, 11:47 AM
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Confusing----for one thing, an H/C car even w/o headers should make alot more than that, unless your port job boogered the velocities. I doubt that 3/4 turn, or even a full turn is going to rob you of that much power.
Consider what you did, re mods, and backtrack to see when you lost your torque. You tighten the rockers merely to take the gap out of the rod to roller connection and ensure that the rockers are always in touch with the valve stems. And the preset is merely to accommodate the change in the physical relationship between the rocker and the valve stem due to thermo expansion. I guess keeping the preset to a minimum is closer to using solid lifters and thus more power, but as far as affecting your power to the degree that it has, I don't believe readjusting the preset is going to solve your problem unless you are really out of the park.JMHO
Consider what you did, re mods, and backtrack to see when you lost your torque. You tighten the rockers merely to take the gap out of the rod to roller connection and ensure that the rockers are always in touch with the valve stems. And the preset is merely to accommodate the change in the physical relationship between the rocker and the valve stem due to thermo expansion. I guess keeping the preset to a minimum is closer to using solid lifters and thus more power, but as far as affecting your power to the degree that it has, I don't believe readjusting the preset is going to solve your problem unless you are really out of the park.JMHO
04-27-2007, 01:38 PM
#6
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comp 1.6 SA
stock replacement lifters
The reason for adjusting them was I had alot of valvetrain noise, is it ok to have a lil? Right now there is none.
Keep in mind that I dynoed 273/306 with bolt ons. That was a different dyno, but on this one cars usually dyno 20 RW less. So that would only put me at 284/313.
To adjust them I did the #1 TDC method. Well any tips as I am going to do this again tonight.
Thanks for the quick replies
04-27-2007, 01:42 PM
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One more thing to answer BUBBA question. This is the only thing I have changed on the car, besides putting a new fuel pump in ( dont see how that would hurt it cuz now my fuel pressure problems are fixed).
Pulled my plugs thinking that might be the problem, looked fine and the gap is correct.
Pulled my plugs thinking that might be the problem, looked fine and the gap is correct.
04-27-2007, 02:16 PM
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Well, if you don't mind getting some oil on ya, adjusting the rockers with the engine running is a pretty good way. Just remove one valve cover at a time and loosen each rocker until it starts to click and tighten is slowly until it stops clicking, plus 1/2 -3/4 turn.
Or you can use one of several methods with the engine off----see Shbox.com site.
I had mine tightened about 1/2 and it was still too noisey for me so I cranked it down another 1/4. I will probably do it again when I get time.
Or you can use one of several methods with the engine off----see Shbox.com site.
I had mine tightened about 1/2 and it was still too noisey for me so I cranked it down another 1/4. I will probably do it again when I get time.
04-27-2007, 05:38 PM
#12
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Those DYNOmite dynos are like mustang dynos right, with an entered vehicle weight? You may want to double check they setup everything correctly because that can really skew the results.
Also, what gear did you dyno in? That can have an effect on the numbers as well.
Trying to compare dyno numbers is sketchy enough as it is, so if you want to do that, I'd get it on a dynojet and run it in 3rd with the converter locked.
Also, what gear did you dyno in? That can have an effect on the numbers as well.
Trying to compare dyno numbers is sketchy enough as it is, so if you want to do that, I'd get it on a dynojet and run it in 3rd with the converter locked.
04-28-2007, 12:41 PM
#14
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Ok, I did it with the car running and there wasnt much oil coming out. Anyway did them all with 1/2 turn and everything looked fine.
Well the car still feels the same.
What else would cause a loss of power that cant be felt? There is no hesitating or power surging, it seems to pull fine.
Just wondering what else there is to look into?
Thanks guys
Well the car still feels the same.
What else would cause a loss of power that cant be felt? There is no hesitating or power surging, it seems to pull fine.
Just wondering what else there is to look into?
Thanks guys
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