Cammed with no power

[2.8RS]

This past weekend I put a cam into my car since I started to get a lifter tick. The car runs fine and the idle is great but it feels like that there is no power at all, feels like its less than stock actually. I can punch it and the car doesn't even want to downshift and it goes nowhere quick. I set the timing to 12* and put some 89 octane in it. I don't think that the computer is too happy with the cam. The cam is basically a Comp 260H with a wider LSA. With the cam I also did a new timing chain, lifters, pushrods, Comp roller tip 1.6 rockers, springs and some lightly ported heads and intake. The car also has 3.1 injectors in it and the fuel pressure is bumped up a little. Before the car ran like a top and now its a little shaky, it runs great but has no power and I don't have much brakes at idle either. Let me know if there is anything that I can do that will give me the power that this cam should have, something is wrong.

Car is an 89 Camaro with a 2.8, it also has headers and full catback. I believe that everything is hooked up correctly.

Cam specs:
Intake Duration at 050 inch Lift: 212
Exhaust Duration at 050 inch Lift: 212
Duration at 050 inch Lift: 212 int./212 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 260
Advertised Duration: 260 int./260 exh.
Lobe Separation (degrees): 114

[gectek]

well you just answered your question...you dont have good brakes, that usually means something went wrong with the install...maybe you didnt adjust the rocker arm correctly or the nut backed off or something to that effect

[2.8RS]

well you just answered your question...you dont have good brakes, that usually means something went wrong with the install...maybe you didnt adjust the rocker arm correctly or the nut backed off or something to that effect

I thought that no brakes at idle just came with the cam lol. The brakes are fine above idle though. I'm going to go back this weekend and reset the rockers if I did anything there.

[gectek]

idk...its not going to be that huge of a cam...

[Superdave]

my cam is way bigger and my brakes work fine...


sounds like your cam timing is off or you have a valve hanging open.. i'd pull the timing cover and make sure the marks are lined up.

[merlot566jka]

are you sure you lined everything up? if you advanced the cam (i think its advanced) you lowered the rpm potential of that cam.

make sure you didnt over set the lash. thatll make all kinds of issues. no pwer being the first....no lobes being the second.

the other things i can think of are fuel related. going lean right now would explain a lack of power feeling. my best fix would be to go up to 19lb injectors and tune. check your fp too. a wideband or even an afr will let you know if yove gone extremely lean.
another indicator would be higher than normal engine temps, knocking, bucking in pe, and glowing manifolds.

the last thing i can think of is a nice sized vacuum leak. that would cause the brakes not working, the lack of power, stalling, running lean...etc etc.

a quick check for the fuel, if you have an afpr, crank the pressure up....go run it again...feel better? thats a fuel issue. if it feels the same or worse, set it back to the way it was and do some more trouble shooting.

datalogging will give you some answers, maybe.

for checking a vacuum leak, i use a smoke machine. theyre about $900!!! other ways are carb cleaner sprayed on a suspected leak (im sure you know this already). be sure to check those injector o rings...if they werent replaced...then you can guess where your leak is coming from. also if you re-used gaskets, it could cause an issue.

the last thing i could suspect, the porting. not saying you didnt do it right, but ive hogged out heads so much that when the air reached the intake ports, they were so much larger than the runners it slowed down the air speed..increased pressure...and made for shitty flow. basicly i make my intake ports into mini plenum. this explained my horrible idle fuel issues and many other issues i was having. it sux to realize this.

with any luck, some trouble shooting will lead you to the cause of no power your feeling. since many things were taken apart and changed, its going to take a good minute to pinpoint the problem.

[2.8RS]

The car runs fine, doesn't overheat and I don't think that fueling is my issue as it ran fine before with the larger injectors. I don't believe that it is a vacuum leak, all the hoses are connected and I used all new gaskets. As far as I know the cam is right but I'll go back and check after I readjust the valves again. I'm going to start with the easier things and go from there.

Something else that I should add is that I have gotten a slight backfire through the intake, I can't run the timing at 10* (stock) and 12* has done it a couple of times. I'm going to ground the car over the next few days and check everything out.

[34blazer]

mine started popping thru the intake when the lobes were wiped. check your valve lash again and make sure the cam is ok. then check your cam timing.

[2.8RS]

mine started popping thru the intake when the lobes were wiped. check your valve lash again and make sure the cam is ok. then check your cam timing.

It did it like maybe twice all day today driving from work and home which is a 30+ minute drive.

I though that if the cam was off that the car wouldn't even run?

[gectek]

oh and please tell me you used some type of HD diesel oil or special formulation of break in lube on that cam...dont want to use regular oil because that will accelerate the lobe wear...also if you get the cam off timing it will backfire or pop and yes it will still run...sounds like that or valvetrain trouble might be your problem...

[torq455]

are we assuming the computer was properly tuned? running very lean with more throttle can cause the no power condition.

[2.8RS]

I haven't tuned it yet but I am going to do an ECM swap pretty soon so that I can, no power if just not in the top end but in the bottom too. I did use break in fluid on all of the new parts, STP oil treatment was recommended to me.

[ForcedFirebird]

Some more input:

The heads are mildly ported, nothing more than a gasket match and shark finning the port dividers. The cam is used with about 50miles on it.

The tune should run the car fine with a bump in fuel pressure, this particular cam is inteded to run on a stock tune - and has been done many times in the 4th gen fbods (obd1.5) - sure it's not optimal, but it does work.

2.8, I would start at your cam timing - seemed as though you were having doubts about the alignment in your IM's, and just might be the culprit - but first start by bumping up your fuel pressure, as stated, lean conditions can cause all kinds of problems. When I first installed a AFPR in my car, the same lack of down-shifting (or upshifting at WOT) would occur if I was on the lean side, but never had any problems with vacuum or brakes. I would also double check the dizzy install (again).

[2.8RS]

I didn't have a lot of spare time this morning but I went and readjusted the rockers and didn't look at the cam. It seems that the rockers were the problem as the car runs much better and has some more power. I thought that is should have made a little more. The dizzy is right but I will go back and check if I am lean and look at the cam timing tomorrow possibly. I'll go ahead and get an AFPR too.

[ForcedFirebird]

The TPI AFPR is a bolt-in.