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Lost 40rwhp on the dyno......what to look for?????

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Old Jun 16, 2002 | 11:47 PM
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Default Lost 40rwhp on the dyno......what to look for?????

Well to say the least it wasnt the happiest night of my life. I went to the dyno this weekend and decided to strap her down and try the 125 split with my TNT kit. Well I made a motor pass as always and only pulled 370/380. The graph was perfectly smooth. Looked as it always does, just 40rwhp down. I typically pull 410/405. I pulled the valve covers today and checked everything out. Springs look fine, pushrods are all straight, rockers fine, etc etc. I have lifted a head a few times since the last time I was on the dyno. I have only lifted the head on the spray. The temp would bounce around a lil and I would turn the car off for an hour or so and start it up and everything would be normal. Could lifting the head like this cause my power loss, yet still drive normal as it is?? I was about to pull the heads and replace the head gaskets and throw in some studs as well. The car is a heads/cam car with 36k on the clock an 24k on the heads/cam. I have been told my springs are prob weak as **** (LS6 springs) but the graph was nice n smooth. If I was getting valve float wouldnt my graph be out of wack?? I know Ill get flamed for this, but after the motor pull I sprayed the car for the hell of it. Thinking if it let go then **** it Ill build it. Well when I sprayed some coolant came out of the radiator but still put down 546/650 with a perfectly smooth graph. What gives here guys? I plan on doing a compression test tomorrow and see what that shows. Is there anything else I should look for or could check myself?? I plan on doin some Atap runs if my buddy would get off his lazy *** and bring it back to me. TIA guys <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

<small>[ June 16, 2002, 11:51 PM: Message edited by: Cammin BeaSSt ]</small>
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Old Jun 17, 2002 | 01:17 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

Maybe o2's are bad or knock retard <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> ttt for you.
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Old Jun 17, 2002 | 01:42 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

cammin i dont think i can help you with your problem but i just wanted to say i saw that 11.00@127 pass you made and it was awesome to see when are you going back to silver dollar to run it again i want to see it go 10's
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Old Jun 17, 2002 | 09:14 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

You did pull the heads after you first lifted them right and replaced the gaskets and bolts etc?
If not then you are losing power from a loss of compression on the affected cylinders. (Blowing the combustion charge through the hold in the head gasket etc.
Cheers,
Chris
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Old Jun 17, 2002 | 11:07 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

Chris, thanx man. Were thinking alike here. I havent replaced the head gasket or bolts yet. I figured I was losing power through lack of compression. I plan on pulling the heads this week and replacing my current gaskets with a better quality nitrous gasket, soe ARP studs, and new springs and possibly roller rockers. How long are lifters supposed to be good for on these engines?? I might go ahead and replace them too with 36k on the clock... O yea and a new timing chain too........ damn its adding up quick...lol

ZR2877....THanx bro, as soon as Iget her bak up to par Illbe down there goig for 10s. I learned how to drive with the bottle a lil better so Ill be giving it another shot. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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Old Jun 18, 2002 | 04:27 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

cammin if you can remember please let me know whenyou are going i really want to see a 10 sec run in a ls1 you mind as well say you have hit the 10's i remember talking 2 you after that run you said you had to press the clutch back in cause you heard some noise you were there man thats one bad SS. see ya
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Old Jun 18, 2002 | 06:25 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ZR2877:
<strong>cammin if you can remember please let me know whenyou are going i really want to see a 10 sec run in a ls1 you mind as well say you have hit the 10's i remember talking 2 you after that run you said you had to press the clutch back in cause you heard some noise you were there man thats one bad SS. see ya</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Lol, I know man, I was soo damn close. O well definately next time. Ill shoot you an email when I go down. 10s are in the bag this time around.
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Old Jun 18, 2002 | 05:39 PM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

badly slipping clutch???
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Old Jun 18, 2002 | 05:45 PM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

Probably way down on compression right now.
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Old Jun 18, 2002 | 07:22 PM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

ProStoc, you hit it on te head man. I got the heads off today and the passenger side was leaking badly from both the middle cylinders. The O rings in the head gaskets were broken. away from the gasket itself. I have th drivers side ready to come off, just gotta get the top bolt on the damn power steering pump. Its a bitch, and no wrench seems to fit it just right. O well, gives me something to do tomorrow.
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Old Jun 18, 2002 | 09:33 PM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

LS6 springs with that monster cam? Damn Ron...might want to think about upgrading the springs.

Chris G
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Old Jun 19, 2002 | 05:17 AM
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Default Re: Lost 40rwhp on the dyno......what to look for?????

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris G:
<strong>LS6 springs with that monster cam? Damn Ron...might want to think about upgrading the springs.

Chris G</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chis, you would be quite surprised if I told you the specs on my cam. Its quite small. I do think Im going with some Comp 918s this time around though.
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