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-   -   Camshaft removel. (https://67-72chevytrucks.com/vboard/showthread.php?t=682673)

muncher 09-18-2015 05:52 PM

Camshaft removel.
 
Hi Everyone. Been a while since I was last on here. I had a 289 mustang that I finished and sold over winter here. Now I am turning my attention to by GMC Steppy. It has a 305 V8 that runs great but could do with a boost in power. I also need to replace the valve guide seals. So I thought whilst I am doing that I could drop in a performance cam and lifters. Some details on the engine.

Fuel injected with original hedders.
Vortex heads.

Can I remove the cam without dropping the sump and removing the front engine cover?
Also what cam could you recommend. Interested in low down punch rather than top end.
Would also like to upgrade the headers.

Any advice/tips/hints I would really appreciate.

Cheers Guys.

68c10owner 09-18-2015 06:20 PM

Re: Camshaft removel.
 
you will have to remove the timing cover. might have to drop the pan too. What year truck is this? Is this a vortec 305 or were the vortec heads added to a early 305? If its a vortec 305, 1996-up engine, then it has roller lifters so you need a roller camshaft. Will need more info about your vehicle to help chose a camshaft.

enaberif 09-18-2015 07:11 PM

Re: Camshaft removel.
 
Advice? VORTEC

muncher 09-18-2015 07:52 PM

Re: Camshaft removel.
 
Hi my truck is a 1987. I have been told it has vortec heads on by the way the rocker covers bolt down. (centre bolts along top of cover). Not sure how accurate that is.

68c10owner 09-18-2015 08:05 PM

Re: Camshaft removel.
 
Quote:

Originally Posted by muncher (Post 7313161)
Hi my truck is a 1987. I have been told it has vortec heads on by the way the rocker covers bolt down. (centre bolts along top of cover). Not sure how accurate that is.

1987 was the first year for TBI and they also have center bolt heads. Chances are you have a TBI 305, not a vortec 305. The TBI has 8 bolts on the intake and vortec has 4. The TBI engines should have a regular flat tappet camshaft but your block could be set up for a oem hydraulic roller.

MalibuSSwagon 09-19-2015 09:15 AM

Re: Camshaft removel.
 
You don't have to remove the oil pan but I would recommend it to properly install the new seals. Might as well replace the oil pan gasket as well.

Desert1957 09-19-2015 10:09 AM

Re: Camshaft removel.
 
spend the money on a used 5.7 , cam and lifters on an old used 5.0 is a waste...IMO

MountainGoat1966 09-19-2015 03:32 PM

Re: Camshaft removel.
 
Build a good strong 383 stroker, you will never look back ...........

muncher 09-19-2015 04:19 PM

Re: Camshaft removel.
 
I thought about replacing the engine but over here they are not that easily available. The 305 I have in has good compression and generally is good. I think a cam and lifter replacement, headers, should give me what I want. I will also be giving it a full respray and tidying up the interior. So funds have to be spent wisely.

Jeramy 09-19-2015 05:06 PM

Re: Camshaft removel.
 
just did a cam swap a couple of weeks ago.

to remove the cam you will need to pull the intake manifold,valve covers,timing(front)cover,at least loosen the oil(sump)pan,water pump,fan,radiator,condenser for the a/c,grill then the center support on the radiator support must be cut and bent out of way, hood latch support needs to be unbolted and moved out of way.

if i ever have to do another cam swap i will be pulling motor and putting on engine stand.

Jake Wade 09-19-2015 07:37 PM

Re: Camshaft removel.
 
...and the fuel pump if it has a mechanical pump.

Jeramy 09-19-2015 09:19 PM

Re: Camshaft removel.
 
Quote:

Originally Posted by Jake Wade (Post 7314004)
...and the fuel pump if it has a mechanical pump.

knew i was forgetting something. mine does not have mechanical being a 92 block

muncher 09-20-2015 06:30 AM

Re: Camshaft removel.
 
Jeramy were you happy with the results of changing the cam. How much of a difference did it make.

Jeramy 09-20-2015 01:51 PM

Re: Camshaft removel.
 
in my case i had put in to large of a cam when building my replacement engine and had to downsize.

MalibuSSwagon 09-20-2015 07:26 PM

Re: Camshaft removel.
 
Quote:

Originally Posted by Jeramy (Post 7313891)
just did a cam swap a couple of weeks ago.

to remove the cam you will need to pull the intake manifold,valve covers,timing(front)cover,at least loosen the oil(sump)pan,water pump,fan,radiator,condenser for the a/c,grill then the center support on the radiator support must be cut and bent out of way, hood latch support needs to be unbolted and moved out of way.

if i ever have to do another cam swap i will be pulling motor and putting on engine stand.

I got away with just hammering out the center support just enough to slip the cam out.

GRX 09-21-2015 02:32 PM

Replace the timing set while you are in there. As mentioned, you should drop the oil pan. That way you can easily get the lip on the timing cover past the seal area of the pan.

Also ... as an engine machinist/builder one thing I have seen commonly overlooked in these operations is new valve springs. Worn springs are more likely to cause valve float. Especially at higher RPMs. An issue made even worse by your new higher lift. Which brings us to another issue - possible spring bind. In short, new springs is a good investment which insures you get the most from your new camshaft.

muncher 09-21-2015 04:59 PM

Re: Camshaft removel.
 
Thanks GRX for the info. As a machinist would you machine the existing cam or just replace with a mild performance cam. Cheers

enaberif 09-21-2015 05:17 PM

Re: Camshaft removel.
 
Quote:

Originally Posted by muncher (Post 7315883)
Thanks GRX for the info. As a machinist would you machine the existing cam or just replace with a mild performance cam. Cheers

Just buy a new one. Never worth redoing the old one.

You'll also need new lifters while your at if you don't have them already.

muncher 09-21-2015 05:29 PM

Re: Camshaft removel.
 
Yeh replacing the cam with a new performance one was my first choice. I have some Hedman headers on order also.

muncher 11-02-2015 04:08 PM

Re: Camshaft removel.
 
Progress has slowed a little due to work etc. Truck is at a mates garage, where the engine has now been removed and stripped. I mean why not:lol:
General condition is great. Replacing the oil pump, valve guide seals and piston rings. I also wanted to put a performance cam in it but have been told the TBI engines are difficult to tune if a perf cam is used. Any one have thoughts on this?

50seven 11-03-2015 02:00 PM

Re: Camshaft removel.
 
just recammed a 305 with an COMP XE262. I like it. just my opinion but I wouldn't go any bigger. woke that little sbc up! good sound still has bottom end torque.:metal:

muncher 11-03-2015 05:19 PM

Re: Camshaft removel.
 
Is yours a carb or TBI. If TBI did you have a problems tuning it in. Cheers


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