i think this is the right place to put this. if not it can be moved to where it needs to be. im looking at a 86 iroc. the head gasket is blown on the 305 TPI. i was wondering how hard is it to change a head gasket on a 305 TPI? what all is involved? and what other things do you all recommend changing since ill already be somewhat in the engine. any help is appreciated.

thanks.

 

It's an all-weekend job for a first-timer. Still, it's a great chance to install a hotter camshaft. Lots and lots of choices, but I'd suggest a COMP CAMS part number 12-388-4. You'll also need new lifters and lube, and a new timing chain. But you should be able to do the cam and related for just over $200. For the head gasket, there are a few ways you could go, but I'd suggest a FelPro 1094.

 

Its not particularly hard if you label the hoses and wiring as they are disconnected, just takes some time the first time you do it.

While you are in there, it would be a good idea to do some maintence that often gets put off on these cars. New timing chain and gear set, new seal on the timing cover, new belts and exhaust manifold gaskets (factory didn't use them on the exhaust manifolds sometimes, but good to put a set in now).

If you are asking about the work involved in doing head gaskets, then a camshaft swap and the related tuning involved afterwards is probably a bit over your head at this point, but once you get familiar with it it isn't too hard.

 

I'd say it's a major undertaking. The hardest part is the exhaust manifolds if they haven't been off for a while. If you have a fair amount of wrenching experience, a good selection of tools, and a lot of patience, it's doable. But it's not "easy". There isn't a lot of room to work around a V8 in the third gen.

 

Unless you just have to get this thing running immediately, do the cam. This one pulls enough vacuum to not screw with the computer, and it's bad enough to pull the intake manifold once. If you can, also do an aftermarket TPI base now also. Edelbrock's is probably the easiest to obtain. The runners are easy enough to change later. But choosing between cam and intake, do the cam now.

 

The problem with doing a cam swap now, is that it just adds to an already big job. To remove the cam with the engine in the car would mean taking out the rad and fans, and evac/recharging the A/C system as well. That adds quite a bit of time and complexity to an already pretty big job. For someone fairly new to this, I would recommend against a cam swap at this point. Just doing the head gaskets will be tough enough for a first timer.

 

ill eventually do a cam. if not a bigger motor. im going to tech school to be a mechanic and was going to take the iroc to class with me. which is why i was looking for more of a project. and i found one i like. i have some knowledge when it comes to changing a head gasket. just haven't done it on a 305 TPI. i have the tools and a few buddys in my neighborhood that can help with the gasket and have tools if i don't have them. i was just wondering what it involved as far as the 305 TPI being the motor? and what else should be changed since i was already into most of the engine to begin with?

 

It's really just gaskets. If you start modding it, it's endless. See how the cylinders look. Maybe check the valves for leaks and replace the valve seals if it hasn't been done before. Make sure you torque the heads properly. Use good quality (Felpro) gaskets. Change the oil before you fire it up. Even a little antifreeze in the oil can eat the bearings. Don't forget the distributor gasket. Go slow and mark everything.

 

when you say mark everything. is that like putting a mark on what it is (i.e. a hose) and then a mark on where it came from? it will be modded. its just i need to get it running first. which includes fixing the head gasket.

 

also forgot to add to the original post. will there be any internal engine damage? im not sure how long the car has siting. the seller did say he tried to start it but it ran horribly.

 

Have you verified that it is a head gasket for sure?

 

Yes... for example, if you take the hose off the intake going to the PCV valve, put a masking tape 'flag' on it and write something like "intake to PCV" on the flag, so you know where it goes 2mos down the road when its still sitting in a box lol.

Extra parts are not a factory defect, I have discovered over the years.

 

i did just find out the car has been sitting for about a week.

 

Depends where the water got to, and how much was there. A week shouldn't be too bad though.

 

thats what i was thinking. so its not to bad if i know what im doing and label what i take off?

 

Take your time, don't rush, and mark parts (small parts, bolts, hoses, wires, etc) as you go, and you should get through it just fine.

If you have a digital camera, take some pics - especially of groups of wires or hoses, before you disassemble - makes for an easy reference later if you need it.

 

thanks for the help. you have helped me out alot.

 

You said you haven't bought it yet, right? Make sure to get some sort of history report. Carfax or whatever. After Katrina, a bunch of flooded used cars have ended up on the market with "just this or that not working."

Also, I've heard that if you just replace the cam shaft, you wont see any performance increase unless you also replace the intake manifold and timing belt, at least. It's a bigger project that the blown gaskets. Unless you're looking to shell out another 300 clams right after you buy this 86 Iroc (good choice), I'd say save it for another weekend. Finding a buddy who's a gear head wouldnt hurt, either.

 

you are right. i am going to run a carfax. and i have a few buddys that are gear heads.