Cam upgrade on dyno loss power..HELP
 

Ok Hi every1 I was very disapointed on sat evening while @ the dyno.

I have done a recent tune-up and oil change.

Also slapped a Zex camshaft in and adj. Meghan racing Cam gear.

New timing belt and New water pump.


Car made 3 less whp and 7 less wtq first pull.

2nd pull made 4 less whp and 5 less wtq.

I dont understand why. :S

What Im thinking is the cam is more agressive and needs a good tunning and playing with the adj cam gear ( which is set at 0 )

Also my timing was pretty much advanced all the way b4.

Now it's pushed back to stock.

This camshaft is supposed to add some decent power and I knoe it needs playing with the gear and tunning but I still dont see why it should be losing hp if nething it shoulda been the same. :S

Even if my timing was advanced like b4 how much extra whp would it give me 3-4 meaning the cam just dropped in did nothing :S Seems a bit weird to me. Just dropped in, it should give me a few hp 4-5. :shrugs:

I had crappy Bosch wires which were in bad shape b4 and crappy bosch plugs which have been replaced with Ngk blue wires / Ngk plugs Step 6's.


Also I seem to be having a prob with my coolant. Car seems to over heat when I come to a stop then it'll go back normal while I drive. The coolant resovior overflows :S. Thermostat was changed a few mths back with a Honda one. Im thinking maybe it could be that or the rad cap? Ne suggstions. Thanks guys.

Almost forgot to mention car is 94 civic si D16z6 :)

did you buy the cam new or used? if you bought it used are you sure you got the right cam?

sounds like you need some tuning. i would have planned to do that while you were on the dyno.

definately need to tune it.

My coolant reservoir was over flowing on my old motor due to a blown headgasket. It had 250000knms on it. How much kms does your motor have?

hrmmm

were you running bigger rims ??
maybe you should check the compression and do a leak down test of the motor,

does your rad fan come on ??

adjustable cam gears on a sohc are pretty much useless. Its not like you can adjust the intake cam and exhaust cam separately, all you can really do is open both the intake and exhaust valves either sooner or later by advancing or retarding the cam...you cannot increase/decrease overlap. As you do this, since the distributor is attached to the cam you will be changing the ignition timing as well, so make sure as you adjust the cam gear you adjust the distributor back to 16 degrees BTDC (assuming your talking about a d16z6).
Which cam did you use? Whats the static compression ratio of the engine?
You definately need some tuning. But if you tossed like a stg2/3 cam in a d16z6, even with all of the bolt-ons, you won't see much of a gain, especially without tuning. This is b/c a more aggresive cam needs more compression.
Try jumping the fan switch (in the thermostat housing). With the fan switch plug in the harness jumped (like you do with the ecu to check the codes) when you turn the engine on the rad fan will come on automatically. If it does then you know the fan indeed does work. Then let the car run for a bit idling with the hood closed and see if you can hear the rad fan turn on.

i disagree andrew. you can move your power band by advancing or retarding the gear on a single cam... it isn't just about overlap!

thus moving the powerband either up or down.
Thats exactly my point aaron, all you can do with an adjustable cam gear on a sohc engine is move the power band up or down.
The whole benefit of having adjustable cam gears is the fact that you can adjust the cams independently, but any adjustments on a sohc cam gear would be like moving both the intake and exhaust cam gears (on a dohc) the same amount (+2 +2) thus bringing the power band down the rpms a little, but doing so will kill top end power a little. Theres always a compromise.
If you want to run a little more overlap on a dohc all you would do is advance the intake cam and retard the exhaust cam (which is desirable on a n/a engine b/c if the exhaust valve is open a little bit it while the intake valve is opening will help pull the air in through the opening intake valve as the last little bit of the exhaust gases exit out of the exhaust valve, this is known as cylinder scavenging). If you wanted to run less overlap (for boost) if the cams you are using have a lot of overlap, you can retard the intake cam a little or advance the exhaust cam a little so the exhaust valve can close fully before the intake valve opens again (which is desirable on a boosted engine b/c you wouldn't want the intake charge to be let out of the open exhaust valve).
So, you can see there are benefits of being able to independantly adjust the valve timing (via the cam gears), which cannot be done with a sohc.
You're right its not just about overlap....theres a lot more to it.

i do see your point and i understand the theory behind adjusting cam gears and overlap, but i'm suggesting that being able to simply move your pb up or down it may be advantageous (albeight a small advantage) depending on the purpose for the motor.

you are going to have to help me with some more tuning some time as i've installed some skunk2 adjustable gears since our last session.

empty your PM box aaron.
You know when i'm available, i'll be glad to help you out.

Yes the motor is D16z6 with 200 k. Runs mint aside from this prob after the cam was installed. The fan does work. And it seems to only cause problems mostly if i beat on it and come to a stop. :s
I havent noticed any overflowing nemore but the coolant constantly stays about 2 inches from over flowing. I dont think theres too much coolant cause for most of the day that the shop put the collant in it was in the proper spot :S.

Could rad cap do this?

If it was head gasket wouldnt it constantly be over heated?

Thermostat was changed bout 2 mths ago from Honda.

Could it be thermo is gone?

But I still dont justify loss in hp. Temp is diff yes cam needs a tune yes, but i did a tune up and car has 14/185/65's in the front as apposed to last time have 15/205/50's.


The cam is a 59-300 Zex Cam purchased New :)

what did it dyno?

your overheating problem sounds like the rad fan is not kicking in. check the relay, fuse, and fan motor.

YOU empty yours zeeman andrew:)



or pm me please i wana talk 2 u

its just about empty now....but it wasn't full before.

Ok another thing I forgot to mention that I thought I mentioned, My wippers and sunroof have stopped werking. One day they just started acted funny sometimes they'd werk if i started car sometimes no, then they just stoped and ever since then my car seemed to get hotter when it came to stops. My car NEVER would EVER move from the right below half point. NEVER.

So maybe it's some relay problem? or something? Fuse is good on sunroof and wipers. I think maybe this may have a problem with the car over heating? The fan does come on.

Is a "Cam Upgrade" something my wife would consider?:rolleyes: :love:

Cheers
pickme:
Cam