Joker's post from the old website.
Alright guys, it took some time to put this together but I think some of you are out in the cold looking for a reasonable stock type build. This is how I build my stock style engines. I have stuff from bone stock to mild build to LS builds so this is intended to be for guys that are looking to basically take an engine out of a 1976 impala and build it using the parts given. I know some guys are getting into mildly built engine with lots of aftermarket parts and that’s ok, I do it too but they don’t need any help when you got $$$ to spend. So lets get to it.
I started with a budget of $ and assuming you can do some of the works yourself like disassembly, light cleaning and reassembly. Obviously it costs more to have a shop do this work to but if you can afford to do that then you don’t need to read this because its not for you. We will assume that it’s a 350, 2bbl complete. This will basically be by the book build and ill give my modifications to each area. Its also not going to be a hold your hand tutorial. Ill state some points of interest but not going to tell you how to remove bolts and how to re-torque fasteners. Most of you in this sport have some sort of mechanical aptitude and your going to have to use it. You also gonna have to get yourself a dial caliper. They are cheap now from the parts stores and handy as hell. They even have digital ones so you don’t even have to count.
This will be a rebuild not a freshen up. I don’t think there is any 1968-1998 engines out there that can just get by with a freshen up. Plus your already in there, might as well do it right. You want an engine to just run, then bearing and ring it, if you want it to make power, needs to be bored and a valve job at min. If I told you to ring and bearing it, you still have a terrible valve job and uneven cylinders and run like a terd and im not gonna be part of that. For those of you that do do that, your on your own, it can work but I don’t do that.
Teardown; Engine needs to be looked over on the outside first to make sure all the bolt holes are usable and the engine mounts bosses are not busted off. Also make sure that the block is not cracked between the 2 middle cylinders from having reg water in it and being frozen. For your newer models look in the fuel pump hole and make sure the hole for the rod is there. If not you will need to drill it later. This is a great time to find out about these thing because its still time to turn back, if you wait till its all done you will be sorry. No real big hitters as far as tearing down. Intake off, heads off, front stuff, rear stuff, crank and rods. Something to keep in mind when pounding pistons out, after you take the rod cap off, slide a few pieces of rubber hose on the bolts to keep from dinging the crank. But before they come out, stamp or punch them for the identifying cylinders. It highly unlikely that you will come across an engine that has not been don’t but may. When crank and rods out, knock cam plug out and oil galley ¼ pipes and knock ins too. There is one behind the rear main cap also. This is a good time to get out the dial caliper and look at the bore size and make sure its not already .040 or better. Blocks that have a ridge at 4.040 are usually no good so need to find another block. You can ask your machinist to offset bore it to help with eliminating ridges. Send the block off to get cleaned, cylinders and main bore checked out. He will advise you on the things you need to do at this point. Get it bored and honed. If needing align honed and/or caps cut discuss getting +.001-+.002 main bearings to make up for the looseness and if he does not think it will do it, get it cut and honed round again. Send pistons to the machinist and get him to take the pistons off but ask for them back immediately, we got some work to do on those before new pistons go on these. Crank also needs to go out and get looked at to make sure it’s the right size. Too small for the bearing turns to a big pain later when putting it together. You’ll end up spending as much or more in oversized main and rod bearings as you will just getting the crank turned. Send off heads to get work done on them. Heads can be tricky. Sometimes its not necessary to et all new hardware. Let your head guy know your not looking to spend a bunch of money and if he can cut the valve you have and grind the seats you have and check and reshim the springs you have it would be great. That saves a bunch. Most of the time if he knows your not wanting to spend a bunch, he will have some spare parts to make your stuff work out. As far as porting I would stay away from nay of that right now due to not knowing what you have and if there is any merit to the work and each head needs something a little different.
Parts; After you get some feedback from the engine shop about sizes, you be able to order up some parts. Hyperutectic flat top pistons are a good choice or a +.100 dome will work even better. Compression is free HP with no penalty. Too high is bad on hot starts but your really not going that high with those 2 choices. Moly top rig is a good choice, they are lighter, take the heat better because of the higher carbon content and don’t wear nearly as fast. Keep compression longer amongst other things. Regular brand bearings will work fine. You should not be touching them anyways, that’s what oils for. When putting everything back to factory or near factory specs, a HV oil pump is not necessary. The HV stuff was introduced at the same time oversized bearings were. It was meant for the engines that were getting “freshened up” and no actual machine work. The clearances in that entire engine oil system wise are too big and less resistance is less pressure, not necessarily less oiling. That a big misnomer in engine building. HV does not hurt but not necessary. Then for a cam, not a giant hitter with these style engines, they don’t make a bunch of power because they are not the restriction in the engine but can be choosen to help efficiencies. The items that make power in these engines are rings seal, valve job, compression and timing. If you use
www.northernautoparts.com for your engine kits, cam #CS1013R is a great choice and for other cheap cams, Summit #SUM-1104 is good also, it makes good power , can be used with any gear and still makes your stock parts work well. Sound good too, I know how important it is to be able to have everyone hear your built engine. Its like having the biggest dick in 3rd grade. Bigger is not better for cams, its all about matching parts.
Parts prep and assembly; After you have ordered your parts, its time to get your rods back from the machine shop. Balancing a derby engine to me is a big waste of money. Ill let you in on a secret, in stock engines 75-80% of the out of balance comes from the rods. You would be surprised just how much better they spin up when just balancing the rods on the same crank throw. That’s as far as I go with that. Plus its free. Get you a small scale from GNC or wherever and find your lightest rod, grind all the rest to match that one and in the process get grind the sharp edges on them too. Don’t spend a lot of time doing it, just get it done. The big end dips into the 50 weight oil you all run and sticks to the crank and unbalances it and takes away RPM’s so you want them sharp edge free. Don’t spend time polishing each one, not a lot to be gained there. Just a stock engine remember. Now send them back to engine shop for pistons and bring him a set of Pioneer or APR rd bolts. They are rated the same psi so I do Pioneers cause they are half the price. That’s about the only failure you do have to watch for in these stock style engine. Using rod bold over and over fatigues them and they are at high risk of breaking.
When you get the block, crank, heads, rods and pistons back from the shop, time to get a little “grindor” inside there. There are a few oil drain back holes in the block that can use a cleaning out. On the back wall of the block you will see them, clean the casting flash out with a grinder or a dremmel tool. Sp? I will lower the front holes that go to the timing chain if the ridge out those holes is too high. That’s usually the demise of timing chains, lack of oiling out the front. Grind a slot to let oil drain out the front onto the chain. Blow all the chips out, hose it down with some water and with some dawn dish soap scrub the crap out of the block and rinse again. Blow with air to dry out and with some 3 in 1 oil or WD-40 on a paper towel, wipe it all down for anit-rust. Expansion plugs in first, little epoxy does not hurt, then oil galley plugs, don’t forget the one under the main cap. Cam bearings put in with a bearing tool, when engine upside down, they go in at 5’oclock. If you’re not comfortable putting them in you machinist can do it. Just make sure then that you do all the grinding before the engine goes to the machine shop. I stick in the cam first with 2 long bolts remembering to put some assembly lube or motor oil on the cam before sliding in. Then push in the main bearings, then the crank and then the main caps with some plastic gauge so you can see where your at after torque is put on the caps. I use a dial bore gauge set off the crank journal diameter but that’s not a tool everyone has. Check each main cap for proper clearance. Stock is .0005 to .0025. I try to hit .0018 to .0022. After you get all of them checked, pull out crank and oil each one and drop crank in and torque bolts 65 lbs. Next, rings go on pistons after they are gapped. Rings need to be specific for each hole. Top 2 rings need to be installed about 1’ down the hole and the gap checked with a feeler gauge. Use the piston to push it down in. About .018 is a factory number. We run engines so blasted hot that they will swell and the ends touch which forces a ton of friction in there. That’s why sometimes the engine dies when hot and wont crank over but after sitting it will then start fine. Cools a bit, cylinder temps go down. The same goes for valve guides. If you can get your machinist to put the guides at .001 clearance instead of the .0005 the factory calls for it will help that too. Oil rings do not need to be done, they serve another purpose and don’t see the temps as the top 2 do.
Rings go in pistons as specified by the box they come in. top ring gap to the top and then each ring after that a third of the circumference apart. Oil the oil rings with some engine oil from an oil can. With a ring compressor, throw on the rod bearing, drop that baby in there and tap all the way to the bottom with the rod journal down but don’t forget the rubber hose on the bottom of the rod bolts. Put the rod cap on with the plastigauge in place, pop it off and if between .0005 and .0025 you ok. Torque to 45 lbs. I try again for .0018 to .0025. Now oil pump and drive in, set the oil pump pick up about 1” from the bottom of the pan. Time to degree the cam in, this needs to be done. The odds of the holes in the cam, holes in the upper and lower gears, slot in the crank all being in the right place is slim to none. I have seen same that were to be ground and installed at 110 come out to be from 108.5 all the way to 110.5. That’s not good. I degree my cams in at 112. Takes some power from on top and puts it where I need it, right when I stomp on it.
Now timing cover, pan, then the heads. Torque each bolt to 45 lbs. Drop oiled lifters in and install pushrods. There are many ways to set lifters and there are many links on here how to do that so I am not going thought it again. Next valve covers, intake carb and distributor. If your carb is good great if not get it rebuilt and do not suggest doing it yourself. Getting a kit and changing the gaskets is not a rebuild. If you cant find someone who can there is an old GM guy down here that is an ace with them and is pretty cheap. The distributor needs an advance curve kit installed in it. About 25 hp and allows you to run low base timing that we need for hot starts and business picks up as soon as you put your toe in it. Junk back on the front and the rear and drop in the dist. Pull it up to #1 TDC and make sure both valves are closed, if not that’s #6 TDC. With long screwdriver turn oil pump drive to point at #1, then hold vacuum advance module pointing at #6 drop in dist. Rotor should point right between #1 and #3. #1 spark plug goes 1 pole clockwise of the wiring hook-ups.
Plugs for make and model used, good filter and 5 qts of some synthetic oil. Turn engine over a bit to prime oil and fire up. Run for about 10 mins and I usually cut oil filter apart and look for stuff other than dirt. If all looks good, add 1 qt more and a new filter. DERBY IT!
$$$$$$$$$
Engine kit $300
Head work $250
Rod bolts $40
Carb build $100
Machine work $350
Curve Kit $25
Misc
Total $1100
I know some of you do it differently but I get asked a ton of the same question over and over again and cant always get to everyone. I don’t mind answering them but I hope this makes some stuff easier when making decisions about you next derby engine. Now here comes the bashing……………………………..