Hi guys (and gals),

I'm new here. I don't own a 3rd gen F-Body, but a friend of mine does. He has an IROC-Z with the 305 and the 4 speed auto. The tranny needs a rebuild and the engine could use some TLC, too.

We want to plan pulling the engine and rebuilding it... and pulling the tranny and having it rebuilt.

I'm sorry if a lot of this has been answered before. I did some searching and didn't find anything that answers these preliminary questions. If it's out there, please refer me to it. Thanks.

1. My friend wants to keep it close to stock. He uses it more as a cruiser than a racer. Keeping that in mind, when we get the cylinders re-bored to clean them up, can we very easily go bigger without buying ourselves a lot more complexity and expense? Or is it just not worth it without changing out more components?
2. I'm new to engine rebuilding, never done it before. My friend has done it once, 20 or so years go, on a 1.6L(?) Pinto engine. We're both mechanically inclined. Any idea approximately how many hours it should take to pull the engine and tranny, separate them, rebuild them, and get them back in. Again, please keep in mind we're competent but not experienced. We're looking for rough estimates to plan approximate schedules. (This, of course, would be our work time. Shop time for machining is what it is.)
3. Is an engine stand highly recommended? I'm in favor but it's my friends money. Can it reasonably be done on a sturdy table or workbench?

Another possibility is that he might buy a 5.7L in need of a rebuild, do that while his car is still intact, and then do the swap. I can research that in the Engine Swap forum. However, I guess a last question would be if that is worth it?

Thanks in advance.
Alan

 

Bigger in what sense? If you're going to bore, you must use larger pistons to match. Changing the stroke on a 305 isn't worth the expense. Some would argue that boring a 305 isn't worth it either.

That's going to depend a lot on how quickly you can comfortably work, while paying attention to detail. A day to pull and a day to reinstall probably isn't unrealistic, as long as nothing goes wrong. The time to rebuild is variable. Give yourself lots of time so you can do everything right, and you're not rushing yourself to finish. My last rebuild took about 2 years, but I might have done it a little slower than most.

It can be done on a sturdy bench. There was even a user a while back who rebuilt his SBC in the trunk of his other car, even. A stand is greatly preferred though.

If you have to do any machining or replace any components in the rotating assembly, then the acquisition of a 350 becomes only a small incremental cost to the project. Plus, you can still drive the 305 while the 350 is being built.

 

When you say cleanup, I think hone the cylinders, not bore. You need to go find a good machine shop and have a conversation with them. You can probably read/learn/understand the techniques, but you may have a significant investment in specialty tools. Some you can rent.

The other advantage of "friending" a machine shop is that you have someone you can go to and ask questions. You may find that the machine shop is more cost effective and would perform better work than you could. Would you pay someone $35 bucks to install the camshaft bearings and the freeze plugs? I sure did. Kept me from having to purchase the bearing installer. Valve job was $45 and I didn't spend hours and hours lapping valves, plus they checked the valve guide clearance for me. In addition, many SBC heads need to be milled flat due to warpage. Spec for that is no more than 0.004" across the sealing surface. They found it and milled it for FREE!

I have rebuilt 7 or 8 engines in my life, but this was the first one for my son. Working on weekends only due to school activities (he's 16), it took us about 3 months start to finish. We could have done it faster, but this was a teaching activity. I have pulled a SBC on a Friday night and had it in and running Sunday night. I drove to school without the hood. No machine shop work. Just replaced cam, crank, rings, bearings, lapped valves, seals, gaskets, etc. It did get a paint job too!

I would recommend an engine stand, but I have done one on a bench. It gets really heavy when you add the crank and heads. Might need to reinforce your bench! (Never done one in the trunk of a car!). I built a wood frame to raise the block off the bench a little bit. It helps so it doesn't sit on the engine components.

I would recommend staying with the original engine if it is just a cruiser. You can run into a host of different issues with a swap-out. Just be aware that there will be more involved to the engine switch.

 

First of all, thanks for the responses so far.

Yes, when I said bore, I meant hone. Since we're going to have it done, we were thinking it could be bored bigger instead of just honed to "clean up" the cylinders. So, it sounds like going bigger with boring over instead of just honing to clean up isn't necessarily that interesting.

We definitely don't plan to do "machine shop" work ourselves. We'll be taking the parts to a machine shop.

The stand sounds like the way to go.

I really appreciate hearing that a "slow," educational rebuild took about three months. I'm guessing we could be in the same ballpark. Part of the reason for doing it is for the experience. Otherwise, we could just pull it and have it rebuilt or buy a rebuilt to swap in.

It also sounds like going for the 5.7 over the 5.0 isn't that interesting, either. We've talked about adding power and that just isn't what my friend is looking for. He wants it to run better and be "tighter." It has 130,000- miles on it, so it's getting due. We also want the experience. He enjoyed the activity 20 years ago and I'm looking forward to my first time.

More responses and opinions would be great. Also, any advice to newbies would, too. Like I said, competent but not experienced... especially in Chevy small blocks.

Thanks again,
Alan

 

My 2 cents in this post would be to research well before you rebuild your first engine. I would get a 350 and a good engine stand. That way the engine could be rebuilt while he drives the car. When you pull it out you can have the new one ready to put back in. Even a 350 standard budget rebuild you will see a little extra power and torque for the same amount of money.

 

Boring is done to clean up wear on the cylinder walls. If the cylinders are worn out-of-round, or too large, then you'd bore it and put new pistons in. It does increase displacement by something like 1%, but that's not the primary purpose.

Not if power isn't your goal, but it would let you have an engine to work on while you're still driving the 305.

 

i second the research, there's many threads on sbc rebuild all overr this site and the internet, just google it. also make sure you have a good manual like chilton's or hayne's both are good... but honestly all your answers are right in front of, the internet. i also agree with finding a older 350 and going through it, then the car will still be able to be used.. and yes an engine stand will make it ALOT easier!

and since power is the goal this should be fairly cheap, but depends on how much time u spend finding parts locally, craigslist, ebay, TGO etc..

also 2-4 months sounds respectively like a good time to accomplish all this

Kohl

 

Excellent point. Do you have to or are you wanting to drive this car or can you afford to have it down? That will give you some time to address other issues you may find in the engine bay. Wiring, mounts, rust, etc.

 

I second the good manual part, but neither Chilton's nor Haynes really fits that description.

"How to Rebuild Your Small-Block Chevy" by David Vizard is a popular choice. I like "How to Build the Small Block Chevy" by Larry Atherton and Larry Schreib.

 

Hi there,

I rebuilt my 305 over the winter. I needed to go 0.40 thou over to clean up the bores, the crank ground and have my valve guides lined by the machine shop.

Some advice I would like give is to:
Take your time, bag and label everything and take photos as you go.
Clean everything thoroughly when you get the parts back from the machine shop if you get work done. Metal swarf gets everywhere and you don't want any of it finding its way to you cam or crank shaft bearings. Use mini brushes to clean out oil passages etc
Make sure you assemble everything with a good assembly lube, this will reduce wear when you first fire her up.
If you hang the rings on the pistons yourselves, make sure you alternate the ring gaps to prevent blow by
Invest in good quality positive type valve stem seals
Intake manifold rubber seals that fit front and back - throw away and use a good silicon sealant.

Parts IMHO should always be changed...
Timing chain/gears
New cam shaft and lifters - these wear bad and are nearly always worn out.
Oil pump
Harmonic Balancer

I'm sure I've forgotten something!!

 

Yes - digital photos are excellent to determine what was routed where. Take pictures of where each sensor is located and the plugs. Bolt lengths and positions even if you bag them. Brackets attaching to the intake manifold. Plug wire routings and where the wire retainers attach.

Don't forget about:

• the plastic seal between the oil pump shaft and distributor shaft.
• Don't pull out all of the pipe plugs that are in the block. There are a couple of them that have to be a certain depth to build oil pressure (per my machine shop).
• Don't reuse pushrods.
• Rocker nuts should be new

My son would ask "Why are we replacing that"? My standard answer - "if it breaks, how bad of a job is it going to be to change it? Yes the old oil pump worked, but think about having to change it with the engine in the car!"

 

Use a pump shaft with a metal connecting collar instead of the plastic one.

There's only one, and you just drive it in as far as it will go. It will bottom out at the point where the diameter of the hole gets smaller.

 

Man oh man did you find a honey of a machine shop

dip block
bore and hone cylinders
install new cam seals
press off old pistons, verify rods, press on new pistons
valve job with 3 angle and new guides
grind/balance crank

$1200 + I buy the parts

needless to say a reman'd long block or repower is in order for me. I guess this is what machine shops do with respect to price when their competition shuts down and they are the only game in town

 

Thanks for the further responses.

As far as the recommendations on the books, they sound great.

I'll push for a stand. It really sounds like it is the way to go.

We're in MN, so the car is parked for about 5 months a year. Needing to have it available to drive isn't necessary, but my friend did indicate he likes the idea anyway. We do have a heated place to work. However, since keeping the car in running condition isn't necessary, is the 5.7 still desirable?