Do I need a new cam?
Thread Starter
Drifting
Joined: Dec 2000
Posts: 1,785
Likes: 91
From: Leander TX
Do I need a new cam?
I have 155K miles on my 85. I have decided it is time to fix my acceleration problem (stumble uppon hard acceleration from stand still or at a roll, sometimes will actually bog the motor down, auto tranny car). I am going to rplace the intake gaskets as they have never been done. I think thats the problem, and the timing chain. Since I will have the intake off and the timing chain off it shouldn't be to hard to put a new cam in, right? Never done major engine work before, but am machanically inclined. I was thinking that with 155k on the original engine that the cam might not have practically any of its lobes anymore as its a flat tappet cam and not a roller cam. So, would I need a new cam. The engine runs great right now other than the stumble, it only puffs upon first start up after sitting a couple of days, and it doesn't burn oil. So, I don't think a rebuild is needed yet. What do you think.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Do I need a new cam? (85WHITEZ51)
Since it still pulls strongly, before you replace the cam pull the valve covers and measure lift. It doesn't sound like you have much cam lobe wear.
I think a new set of heads would do more for performance than a cam.
If you have a smooth steady idle and good idle vacuum don't suspect an intake leak. Look at the TPS setting and base timing. And clean the TB.
I think a new set of heads would do more for performance than a cam.
If you have a smooth steady idle and good idle vacuum don't suspect an intake leak. Look at the TPS setting and base timing. And clean the TB.
Racer
Joined: Jan 2002
Posts: 330
Likes: 0
From: Simi Valley ca
Re: Do I need a new cam? (85WHITEZ51)
Well a new cam could certainly perk it up a bit if you suspect some over-extensive wear. But if the 155k is original miles you might consider going through the whole motor if you are going to take this much of it apart. Even chevys can only go so far.
joe
joe
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Re: Do I need a new cam? (85WHITEZ51)
I was thinking that with 155k on the original engine that the cam might not have practically any of its lobes anymore as its a flat tappet cam and not a roller cam.
Team Owner
Joined: Nov 1999
Posts: 32,782
Likes: 11
From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Do I need a new cam? (65Z01)
Since it still pulls strongly, before you replace the cam pull the valve covers and measure lift. It doesn't sound like you have much cam lobe wear.
I think a new set of heads would do more for performance than a cam.
If you have a smooth steady idle and good idle vacuum don't suspect an intake leak. Look at the TPS setting and base timing. And clean the TB.
I think a new set of heads would do more for performance than a cam.
If you have a smooth steady idle and good idle vacuum don't suspect an intake leak. Look at the TPS setting and base timing. And clean the TB.
Jim knowes :yesnod:
Thread Starter
Drifting
Joined: Dec 2000
Posts: 1,785
Likes: 91
From: Leander TX
Re: Do I need a new cam? (mackeyred96)
How much would a rebuilt short block cost me? I don't want to spend alot of money on a new engine that I wont use that much. For the next few years I only get to drive my car about 5K miles a year so I was think that I could freshen up the engine so it would perform well untill I get to the 200K mile mark. Since a new cam really isn't that expensive I don't mind putting one in now and putting a different one on later. I was probally going to get my heads cleaned up and ported or go with a set of aftermarket heads which I could later move to my new engine a couple years down the road.
I have checked all the sensors via the sensor test kit form MAD. All were good so I checked the timing to the factory specs (can't remeber right now). Haven't done anything with the throttle body yet though. A friend of mine got a rebuild kit for his 91 TPI camaro (engine swap done) for like $14. It came with all new gaskets. Should I remove the throttle body and replace gaskets and clean it or just clean it while its on? What's the best way to clean the throttle body? Carb cleaner?
Thanks I really appreciate all the advice and help. :)
I have checked all the sensors via the sensor test kit form MAD. All were good so I checked the timing to the factory specs (can't remeber right now). Haven't done anything with the throttle body yet though. A friend of mine got a rebuild kit for his 91 TPI camaro (engine swap done) for like $14. It came with all new gaskets. Should I remove the throttle body and replace gaskets and clean it or just clean it while its on? What's the best way to clean the throttle body? Carb cleaner?
Thanks I really appreciate all the advice and help. :)
Racer
Joined: Jan 2002
Posts: 330
Likes: 0
From: Simi Valley ca
Re: Do I need a new cam? (85WHITEZ51)
Be careful of putting heads on your exisiting shortblock. If you have a puff of smoke in the morning (which is normal for the age) new heads just might pull oil past the rings. It almost will be a given.
I am looking for a transplant myself and have found 3 options on autocenter. My motor has 1,000 miles on the rebuild and it is shot.
Check out their motors in my case option one is a 265hp for a 2 seal main, also a 320 hp motor, and the last is a zz4.
Now they are willing to work with you, I also found the zz4 shortblock at the best price right now of 1,825 with edlebrock heads with heat riser (egr) of 440 each and non roller cam of 75 to 120.
I am current in the realm of the 320hp version with the 265 hp cam to try and avoid changing my eprom (which is why you replied to my ealier post on removing the computer) thanks again really helps. They will switch parts for you to try and make it right.
Their site has mainly full crate motors, but if you call them they have the prices for the components as well.
http://www.goautocenter.com/zz4_350.htm
joe
I am looking for a transplant myself and have found 3 options on autocenter. My motor has 1,000 miles on the rebuild and it is shot.
Check out their motors in my case option one is a 265hp for a 2 seal main, also a 320 hp motor, and the last is a zz4.
Now they are willing to work with you, I also found the zz4 shortblock at the best price right now of 1,825 with edlebrock heads with heat riser (egr) of 440 each and non roller cam of 75 to 120.
I am current in the realm of the 320hp version with the 265 hp cam to try and avoid changing my eprom (which is why you replied to my ealier post on removing the computer) thanks again really helps. They will switch parts for you to try and make it right.
Their site has mainly full crate motors, but if you call them they have the prices for the components as well.
http://www.goautocenter.com/zz4_350.htm
joe
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