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Rebuilding a 302 Cleveland

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    Rebuilding a 302 Cleveland

    I'm going to start off by saying this will be for sale once built, however if you plan on using it on the street it could be a little bit raucous.....

    I picked this up in part payment for building the 502 big block I posted on here a while ago and the Toploader that went with it, it had been rebuilt and then left outside which unfortunately led to a lot of internal issues. Mainly very mild surface corrosion in the bores, whilst the engine still turned over by hand this obviously isn't any use for ring sealing.
    So I will be honing the block, adding a new oil pump, replacing all bearings, replacing the cam as I want something meaner in there, going through the heads, most probably doing some extra port work to the intake and exhaust side or swapping over to some ally heads and then selling once broken in and hopefully dyno'd with a printout if my friend gets his up and running

    I ended up tearing the engine down in the boot of my car as it already had the top end off when I picked it up and I was too lazy to go get the engine hoist to lift it out as one. It had a few nice bits like forged pistons, Weiand ally water pup, Edelbrock intake and a remote oil filter take off although I'll probably put a standard location one back on

    What a shame to re-build an engine and then leave it outside like that.


      The good news is the internals should be ok, bar the cam as I ran the numbers and its way too small......runs out of puff at 5000rpm


        I have an Edelbrock Performer Plus cam in my engine. Supposed to be good from idle to 5500rpm. On the rolling road it ran out of puff at 4750, way short of the stated spec. Something to bear in mind when considering the US blurb on performance figures. This said whilst the motor is a little short of top end horse power it has really good low end grunt and is a nice smooth driver on the road.


          I'll be dropping in something that goes all the way up to 7500
          The Cleveland heads breathe really well unlike stock Windsor ones which is where you could be falling a little short?


            Originally posted by nuggets View Post
            I'll be dropping in something that goes all the way up to 7500
            The Cleveland heads breathe really well unlike stock Windsor ones which is where you could be falling a little short?
            I've got the old iron GT40 heads on my car with larger runners and valves. The old 289 heads are a bit restrictive, especially if you have the smog ones. I'm not sure about the bottom end going all the way up to 7500 unless you strengthen that as well.


              I stripped the heads today so I can start the port work and then rebuild with new valves. After two valves the xxxxy little screw compressor annoyed me and I sacrificed a flywheel bolt creating a makeshift stud to adapt my big compressor to these heads. I'll make a proper bolt down plate using the ARP bolt and weld it to it so its like the other adapter I have and wont bend but this did in a pinch. I didn't have the time or inclination to make a proper adapter today

              These are the bad valves, where water had gotten in and just started to make them oxidise. Thankfully the heads will clean, most of that orange stuff wiped off with a little brake cleaner. One valve did need a little more persuasion than the others......but thats what hammers are for

              A nice bonus to find was that when these heads were last apart the exhaust guides were done

              Looking through the head you can see a lot of meat that can be removed, exhaust guide will be blended back, reduced in height and shaped to a tear drop. I'll enlarge the throat of the runner and exit where someone has started removing material. Cleveland intakes flow pretty well but will get similar treatment.

              I wont be spend countless hours on these as to make the most of them you need port plates like my old heads (blue ones below) these have the exhaust side of the head milled off and an aluminium insert added to raise the exhaust runner to a more favourable position. This improves flow and velocity by creating a straight exit for the exhaust. Of course at this point it makes more sense to buy raised port ally heads

              These were my old 302 Boss heads, same as Cleveland heads but with modified water passages for Windsor fitment. You can modify any Cleveland head to fit a Windsor block with the correct machine work. If anyone wants info I'll add it in

              Notice the valve de shrouding and bowl blending. I will do much of the same work on these heads ( the shiny area round the valve and reduced spark plug bump)

              This is the basic info on porting a set of these heads, a lot of it will be down to feel though

              I have outlined the fire ring on the gasket using a sharpie. This will be the max boundary on the head I can go to.

              Intake valve pictured next to point marked 1; This will be blended and then I will dig into the chamber to relieve the valve and improve flow round the valve head as charge enters the bowl

              Spark plug bump marked 2; I'll put a plug back in and grind this back as much as I can to leave the plug just protruding past the end of the threads as right now it will sit under flush

              Area 3 and the bowl in general where there are the remnants of a casting sprue or something similar; This will be ground back and the chamber smoothed out in general to remove any potential hot spots

              Area 4; Much like 1 this will be blended but note I cant grind any of the head surface away to create a smooth transition as it is already flush with the fire ring

              I will be replacing all valves with one piece stainless and single groove locks rather than the nasty triples, adding in springs for a solid tappet cam and most probably machining the rocker bosses down to a flat, drilling and tapping for 7/16ths and machining the valve guides to accept positive style stem seals
              Last edited by nuggets; 16-06-2019, 09:21 AM.


                Thanks for taking the time to post the photos and info. - makes for a very interesting read.

                I have a '65 with its original A Code 289 - no idea what it has inside but it still pulls strongly through the gears, the Arvinode reproduction exhaust maximising the aural pleasure!

                Quite tempted to have a go at a bit of porting and relieving, as it's pretty much cost free and I have a spare pair of heads I could take my time on.

                I guess it would be easiest if I get hold of a compact hand unit - maybe a mains Dremel copy.

                Assume it would make sense to check the springs and valves at the same time and lap them in, with new stem seals.

                Not having to have the car off the road at the same time, it should prove a therapeutic experience

                '65 289 "A" Code GT Optioned Coupe, with 4spd Toploader and Arvinode exhaust - sounds great! :D :gears


                  You will need something stronger than a dremel, I use one of these with carbide burrs



                    I ported and rebuilt some 2V Aussie heads back in 1999 or so for my 351c. Put a ton of money into them with Manley valves, hardened exhaust seats, solid bronze guides, machined for rocker studs. Set up for a hydraulic roller cam. Wasn't impressed with the power output and chalked it up to internet hype and misinformation. I had the same intake and it layed over hard after 4000 rpm's. A Weiand Xcellerator gained me almost 30 horsepower and leveled out the torque curve nicely. Still didn't make horsepower numbers you thought it should. I had rolling road dyno's to confirm those numbers.

                    I'd ditch the multi groove valves if you plan on running any sort of lumpy cam and a lot of spring. Those original valves had a habit of snapping the heads off for no rhyme or reason when pushed. I also didn't like using those white teflon valve stem seals. They only last a few hundred miles before starting pass oil and puff smoke out of the tailpipes. Don't port the chamber out to the head gasket fire ring. Install the head onto the block and trace the bores.
                    Last edited by MeZapU; 16-06-2019, 08:05 PM.
                    Black 1985 GT, 408w, high 10's
                    Red 1988 Coupe, 5.0, Survivor car
                    Yellow 1973 Mustang Mach 1
                    Black 2012 5.0 GT, 6-speed, Brembo brakes, 3.73's
                    White 1966 F-100 Shortbed Styleside, 390, Tremec 3550, FiTech EFI


                      I wont be using bronze guides, iron guides are much easier on tooling, wont be using a hydraulic roller cam either. Solid flat tappet is the only way to go unless you want to splurge on a solid roller

                      Intake will be going, I get all Weiand stuff at dealer rate so I'll be using one of their intakes or a Street Dominator if I can find one

                      Multigroove valves will be the first thing to go and be replaced by PEP&QC stainless valve

                      I've never had an issue with the teflon or green viton ones, the chamber wont be ported out I used that to see if there was anything that needed doing as on the Chevy heads you can cut a little bit back to the fire ring if room to further unshroud. I will be cutting into the head under the fire ring to unshroud the valve slightly with a 1/4" bit
                      Last edited by nuggets; 16-06-2019, 08:50 PM.


                        Well I did almost all the porting today in two die grinder ate through that cast iron like it was made of Wheatabix. Did manage to get a piece of cast iron in my eye though so had to make a quick trip to the hospital.

                        First job was to blend out this as cast step, as the air comes down into the chamber it hits this step and bounces off towards the centre of the valve which is pointless. So by removing this more air should head towards the outside of the valve which is more ideal
                        I also opened up the throat and blended the short turn radius, again just to remove the as cast step as per the diagram in my previous post

                        Moving on to the intake ports I started to hog out material out to the size of the previous attempt made, it was pointless given porting the first 1/4-1/2" of the mouth wont do anything. Once this was done I started to blend the throat removing any bumps and making sure I had a nice smooth path to the valve.

                        The finished article looks a lot better than the previous guys attempt, I may enlarge the ports further as theres more meat that could be removed. However this wont be done until I have a 4V intake gasket to check against

                        Final job was to rough out the chamber, note the sacrificial valves to protect the seats. Even though they'll be re cut this helps keep any re work to a minimum. Just remember if you're going to slip do it before you have the heads machined! I'll be taking 5 thou off these anyway to clean the faces so that witness mark will disappear

                        With that done I'll hit the chambers with a stone to smooth out the cuts and I will also need to unshroud the valve fully with a smaller 1/4" or 1/8th" bit as I didn't have anything small enough in my stash of burrs

                        Only job left after that will be to use some cartridge rolls to smooth out the intake and exhaust ports a little more, not polish!! Just blend the cuts so theres no ridges, I did a pretty good job of roughing it out as you can see from the pics but a cartridge roll will finish the job. Then once done both heads will go to the machine shop and have the guides milled out close to the roof of the mouth before I blend whats left to a blunt point facing into the flow, will probably do that there and then have them skimmed, machined for push on stem seals and screw in rocker studs before a full hot tanking to remove any crud


                          Looks good. Do you measure the volume of these runners to compare with the more performance oriented ali heads? I think you should try and get the inlet and exhaust runners the same volume. (I mean compared to each other so all the inlet are the same volume and al the exhaust the same)


                            The exhaust side is generally smaller, I don't have a set of ally heads to hand but I would say these will out flow an as cast set once I'm done. May go back and take another 1/16th of meat off the walls and roof. Don't want to remove anything from the floor though


                              Finished off the de-shrouding and chamber blending today. Smoothed off the rough edges using cartridge rolls and an 8mm bit to finish the valve areas

                              Rough cut done with the carbide burr, 8mm ball

                              Out with the rolls to finish the bowls

                              Green marker is where I went over them again after the first run and looked for high spots that needed tweaking, sometimes you cant see everything when grinding

                              Prime example here where there is a small step seen by the exhaust valve, marked it up and smoothed it out afterwards