Why did my Z06 dyno so low? Lots of mods, low numbers
09-06-2005, 08:52 PM
#41
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man you hit some valves. If your cam is over 600lift, you have little to no piston to valve clearance. You said you bent them and then sent your heads out. Well if you put the same heads back on and did not fly cut you hit again. This is your problem. Also 9k for the install and they didnt check the clearances? Oh and you have 2.055 valves with milled heads, and no fly cutting, Im gonna say you hit.
09-06-2005, 09:06 PM
#42
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Originally Posted by roadrash9r
man you hit some valves. If your cam is over 600lift, you have little to no piston to valve clearance. You said you bent them and then sent your heads out. Well if you put the same heads back on and did not fly cut you hit again. This is your problem. Also 9k for the install and they didnt check the clearances? Oh and you have 2.055 valves with milled heads, and no fly cutting, Im gonna say you hit.
09-06-2005, 09:21 PM
#43
Originally Posted by roadrash9r
man you hit some valves. If your cam is over 600lift, you have little to no piston to valve clearance. You said you bent them and then sent your heads out. Well if you put the same heads back on and did not fly cut you hit again. This is your problem. Also 9k for the install and they didnt check the clearances? Oh and you have 2.055 valves with milled heads, and no fly cutting, Im gonna say you hit.
the first set hit and the heads that are onthe car now are not milled.....so before u start stating facts that ur wrong about know some facts.....
09-06-2005, 09:38 PM
#44
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Originally Posted by roadrash9r
man you hit some valves. If your cam is over 600lift, you have little to no piston to valve clearance. You said you bent them and then sent your heads out. Well if you put the same heads back on and did not fly cut you hit again. This is your problem. Also 9k for the install and they didnt check the clearances? Oh and you have 2.055 valves with milled heads, and no fly cutting, Im gonna say you hit.
09-06-2005, 10:40 PM
#46
It's hard for me to believe with the cams duration and lift along with the 2.055 intakes that the pistons weren't notched. Looks to me an over rev or a little valve float could be curtains. Did anyone actually clay or use a dial indicator to check clearances?
09-06-2005, 11:47 PM
#47
Originally Posted by bigdsz
It's hard for me to believe with the cams duration and lift along with the 2.055 intakes that the pistons weren't notched. Looks to me an over rev or a little valve float could be curtains. Did anyone actually clay or use a dial indicator to check clearances?
motor has already been to 7200 and everything is fine with it,,,,,,
09-07-2005, 10:28 AM
#48
Do what I suggested and see what happens.
That cam can make gobs of power but you need everything else along with it. You exhaust is probally fiine. You are loosing much power with compression and the fact your not running a 90/90 setup.
I bet 440 is easy to gain by flycuting, milling, running a .045 gasket and having a nicely ported TB on there. I still wouldn't be impressed with 440 with that combo but it is a nice step in the right direction.
That cam can make gobs of power but you need everything else along with it. You exhaust is probally fiine. You are loosing much power with compression and the fact your not running a 90/90 setup.
I bet 440 is easy to gain by flycuting, milling, running a .045 gasket and having a nicely ported TB on there. I still wouldn't be impressed with 440 with that combo but it is a nice step in the right direction.
09-07-2005, 10:58 AM
#49
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Originally Posted by bigdsz
It's hard for me to believe with the cams duration and lift along with the 2.055 intakes that the pistons weren't notched. Looks to me an over rev or a little valve float could be curtains. Did anyone actually clay or use a dial indicator to check clearances?
Originally Posted by Frans96SS
motor has already been to 7200 and everything is fine with it,,,,,,
scary
09-07-2005, 11:32 AM
#52
Guys lets not make this a useless topic. I think we can all see the shop did a subpar job at best for a customer spending 9000 dollars. I myself couldn't let the car leave mt shop without finding the problem. This however needs to be discussed between the owner of the car and the owner of the shop and dosen't need to be something we drag in the mud. There is defentially a problem with the car and the owner is looking for more power. I would like to see this stay on topic so we can help him figure out why his car dynos about the same as a TR224 camed stock ls6 headed car.
09-07-2005, 11:36 AM
#53
Originally Posted by JZ'sTA
Guys lets not make this a useless topic. I think we can all see the shop did a subpar job at best for a customer spending 9000 dollars. I myself couldn't let the car leave mt shop without finding the problem. This however needs to be discussed between the owner of the car and the owner of the shop and dosen't need to be something we drag in the mud. There is defentially a problem with the car and the owner is looking for more power. I would like to see this stay on topic so we can help him figure out why his car dynos about the same as a TR224 camed stock ls6 headed car.
it wasnt 9k for just heads and cam his car was done stock when it came to my shop now it has heads, cam, kooks 1 7/8, kooks x-pipe, borla cat back, kirban shifter, spec 3 clutch, dte brace, vararam, plus, wires, and a list of other parts.....yes his car is down on power but i think we can easily get another 20 out of the car with porting the tb, airing up the tires, and leaning it out alittle more up top..... i think we can get 430 out of it
09-07-2005, 12:03 PM
#54
Originally Posted by JZ'sTA
Do what I suggested and see what happens.
That cam can make gobs of power but you need everything else along with it. You exhaust is probally fiine. You are loosing much power with compression and the fact your not running a 90/90 setup.
I bet 440 is easy to gain by flycuting, milling, running a .045 gasket and having a nicely ported TB on there. I still wouldn't be impressed with 440 with that combo but it is a nice step in the right direction.
That cam can make gobs of power but you need everything else along with it. You exhaust is probally fiine. You are loosing much power with compression and the fact your not running a 90/90 setup.
I bet 440 is easy to gain by flycuting, milling, running a .045 gasket and having a nicely ported TB on there. I still wouldn't be impressed with 440 with that combo but it is a nice step in the right direction.
ok so by cutting the pistons that will lower the compression ....and by putting a smaller head gasket on it it will raise it back up proably to where u started with .... so the point of that is? not trying to be a dick just asking?
09-07-2005, 12:25 PM
#56
Looking at the posted specs on that S cam (assuming about a 50* IVC and EVO of 60* at .05) , it sure looks like it would like to rev, and the fact that your graph carried to 7k without much of a drop in power indicates that it is worth it to try the Fast 90 intake. I could see you picking up 20 - 30 RWHP and carrying that gain out to 7K. Combine that with a touched up tune of 10 RWHP, and you should be happy with that. The area under the HP curve from 5500 - 7000 would be pretty stout.
09-07-2005, 02:01 PM
#57
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Man Wow personal attacks here. I have seen cars rev to 7000rpm while hitting the valves lightly. Piston to valve was checked with clay, and showed 1/8 inch. If you like I have pictures of the notchs that got cut in the pistons. Car ran great and put down good numbers. This was on stock heads milled .010 and a 224/228 581 581 lift cam. As far as Lift having nothing to do with it your wrong. Lets have 300 degrees at .050 at .100 lift and see if that hits!!! so yes lift comes into play. childish yes but to the point. Im just trying to help this guy out. All you guys that just want to lift yourself up by pointing out someones oversight need to add some useful input. thank you to everyone who had an inteligent and helpfull comment.
09-07-2005, 02:02 PM
#58
The reason for the thinner gasket is quench. Optimum quench is .035-.040. So if you use a Cometic .045 gasket and the piston is out of the hole .006, then the quench is .039. Tightening the quench should be good for 10 hp. Also notching the pistons really doesn't drop the CR significantly, but it sure does give you some cheap insurance.
09-07-2005, 02:11 PM
#59
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quote from shawn "No we didnt flycut the pistons. The first set of heads were milled unbeknownest to Fran and he bent all the valves on the first start up. So we sent out my heads to get them worked, no milling, and it seems to work fine now. I was wondering if they were slighty bent myself."
Read to fast and led me to believe he sent out the damaged heads to be worked...
You got me
Read to fast and led me to believe he sent out the damaged heads to be worked...
You got me
09-07-2005, 02:54 PM
#60
Originally Posted by Frans96SS
it wasnt 9k for just heads and cam his car was done stock when it came to my shop now it has heads, cam, kooks 1 7/8, kooks x-pipe, borla cat back, kirban shifter, spec 3 clutch, dte brace, vararam, plus, wires, and a list of other parts.....yes his car is down on power but i think we can easily get another 20 out of the car with porting the tb, airing up the tires, and leaning it out alittle more up top..... i think we can get 430 out of it
I could care less what the 9 thousand was spent on, and that is why I clearly stated we need to stay on topic. Airing up the tires is pointless. Maybe yu can run a shortbelt and throw the car in a climent controlled room in 60 degree AC. What is the point of that. Nobody wants a dyno number when your changing the way the car drives every day. Porting the TB and leaning her out are good starts.
Also the reason I said subpar is because P/V was never checked. With a cam as big as this and work done to the heads checking p/v is very important. Again that is over with and done with. If you feel you did nothing wrong then thats fine and either way a waste to argue over. If my post upset you I am sorry. Now lets get this back on topic.