Recent content by Assiemick

Im doing a similar project now. The heads i have are on a 273 and are 68cc, im using race pistons for a GM Holden that has the same bore. I will be making raised head pistons from these. The heads i have i need to have another look at the numbers but dont seem to ring a bell. However the valve...

My GM 253 4.2 is very similar also but the valves it had were already the biggest that could go in. The biggest thing that improved its performance was the porting. Core shift on casting on the heads and as well as the intake manifold meant that some of the ports had been restricted almost half...

I found the existing clearance of valve to cylinder is 0.055 After a 40 over bore and the installation of 1.88in and 1.6ex To maintain the existing clearance the valves need to be 1.86175in and 1.56ex That's .040 on the OD of the valves Really only 20th removal or 0.5 of a mm

Yea Yeah Chrysler stopped building cars here in about 1982. They also stopped selling cars here. Back in those days if you had a Valiant nearly everyone would harass and run you down. GM and Ford dudes. These days Chrysler are very much sort after. Some of that could be the beatings we would...

Than thanks for that address. I just took a photo and width of the two valves. I know the bores to head won't all perfectly line up but assuming the valves and bores are all central, the best will be an average clearance to bore. The photo where the readout is white should have been the...

Upon further thought I will leave the quench in the chambers untouched. I will be removing sharp edges and polishing the chambers, this will only make the chambers bigger but I will get the comp back with the piston. One valve has rust hoping its just a case of water got in whilst sitting...

Best to keep 40th on the quench area so zero deck 40th head gasket perfect. On my heads only a real small quench area. Considering removing it all together, create a kind of hemi chamber, push the piston up into the chamber to get the 10's. Those race pistons are 12mm thick on the face some...

Yeah your right ive been on the scat web sight. They do a 6.200 and a 6.250. For Chev. The big end are a bit wider but the BE pin is .024 smaller. I could get a push up centre of pin to top of 6.220- 6.270. I think thats a good idea. 6.238 is what i needed to get the race piston to the position...

Ive been doing a bit more number crunching. With the 3.58 crank and 6.123 rod holding the speedway racing piston. The piston will actually be 0.040th or 1mm below the deck. To gain a zero deck its just a .040 thou cut. this will give me a 9:1 comp with the 68cc heads i have, 63cc heads will give...

I have a pair of bonnet scoops off a Dart i think. Be a bit of a **** stir for ford dudes seeing 302 badges on those scoops

I was looking at the alloy heads around at the moment. They all seem to come with 2.02 intake I would be prepared to machine custom seats for the 1.8 intake. My intention is to port out as far as i can go. Remembering its a small engine ports and valves dont have to be as big as on a 360 to get...

Sorry that didnt turn out how i typed it but i think if you take the time you can make it out. The first figures on each line is LA the last is the difference maybe write it out on paper.

Because im running a stroker crank the 6.123 rods will work in my project. Even thou the Holden 253racing pistons are 2.92mm lower than the Mopar. For those not going to stroke thier motor maybe rods with around the length of 6.250 as suggested by Rumblefish360. For the racing piston to achive...

It's early days the motor has not been fully pulled down yet. My thought on the rods is I'm going to either try and order the scat rods with the smaller pin bushings or have them rebushed. The piston catalogue lists clips so I'm guessing these are for a full floating wrist pin. I will go full...

Im still looking at options, being a machinist my options are varied outside of the box so to speak. The heads have the early angled manifold bolts. I believe later 273 heads are the same as all the rest of the LA mills. I will point out for those reading. I have an Edlebrock performer manifold...