March 12, 2015 9:41 a.m.


this AD by this mechanic says $800 core exchange for a block and crank assembly

seeing if anyone would look it over and see what you think?? as i have a block and crank to exchange with him.

NOHOME UltraDork
March 12, 2015 4:52 p.m.

Those pistons do not look new.

March 12, 2015 11:15 p.m.

My guess is the engine is still standard bore and cleaned up with a hone. That said, I would want to see receipts, documentation, etc. before taking a shortblock I bought off Craigslist and running with it.

I'm noticing a lot of cleaning, polishing, honing etc. I'm not noticing resizing, turning, boring. Not every block cleans up with a hone. Not every crank cleans up with a polish. I'd want to know where he got the machine work, cleaning, mag check, etc. done.

Truth of the matter is, unless whoever goes to look at it with you takes a set of mics and bore gauges with them, and Jose allows them to disassemble the engine and check clearances, they can't tell anything by looking that you can't, apart from recognizing readily apparent finish problems.

I would also want to know what qualifies Jose as a "Mustang Mechanic". I've changed a Mustang's oil before, am I a qualified Mustang Mechanic?!

Also, unless you've already got the swap done and are just replacing the motor, or simply prefer Ford power, I'd consider a 5.3 LM7 engine. More power, less weight, and cost is probably a wash at this point.

Skervey Reader
March 12, 2015 11:53 p.m.

Im with these guys, my GT40P motor (with heads, oil pan, intake, everything but front exorcises) with a "said to be 45K" on it was $500 and the motor is clean inside, I know it is not rebuilt but still very clean. This sounds like a start up shop trying to sell product rather than take care of customers. If its a good shop doing the work you will be on a waiting list or ask them to do the work, they wont have time to have 302's built ready to sell on CL.

Saying all of that im going to stick with my guns and say the 302 (SBF) is still a good option for a swap RX7 although I am bias I am working on a swap now. My build in progress-. The 302 has good power and tons in the form of aftermarket and know how. It is not a 600HP monster but will be fun for cheap with a pile of replacement parts still in the junk yard. That being said if you do want to have 600HP EFI twin turbo ect. ect. one day go with the LS motors they are the next small block to take over the world. Just spend some time looking around, ask a shop how much it would be to build a short block for you and compare that to what they are asking. Do some looking around and see if you will be happy with what the 302 brings to the table or if you are looking for something more. Either way the RX7 is a good start for any motor, that or the obvious answer MIATA!

Almost for got no matter what you do have fun and post pic!

pres589 UltraDork
March 13, 2015 4:38 a.m.

Why did they paint the lifter valley? I've heard of special paints being applied there but that looks like plain old red engine paint from over there. Same with the area that faces the back of the water pump.

darthmayndawg New Reader
March 16, 2015 2:29 p.m.

In reply to Ambitious_But_Rubbish:

Thanks for the input, i currently have two RX-7 FC's one complete and one just needing the motor (everything the listing showed) and a pair of heads.

My buddies are doing the Chevy swaps I'm doing the Ford. The Ford opportunities fell on my lap easily so i went with the grain. I suppose those are good questions to ask before giving up my old block and crank assy. I have a few qualified buddies that I will have tag-along as well.

darthmayndawg New Reader
March 16, 2015 2:44 p.m.

In reply to Skervey:

WILL DO!! I'll post as soon as i get a chance...

I called and apparently they don't build them until you order them. And I'm with you on the 302 being easily modified, slightly on the conservative with power, and easy to replace parts.

A crank assy is almost triple what the cost of this "complete" motor would be. Patience has been my friend for the most part and has kept mefrom spending too much.

akylekoz New Reader
March 18, 2015 7:14 a.m.

racsirx on corral.net parts out nice 5.0 mustangs LX to Saleens. He would be a great source of a 5.0 and T5 with supporting gear.

Beagle New Reader
March 19, 2015 7:19 a.m.

I don't want to come down on Jose, but it looks like it's been cleaned, new rings and bearings, and the major expense is the ARP main bolts. Probably decked with a belt sander, bottle brush / brake hone, no real machining done. Glyptal paint is pretty old school. This has all the earmarks of a 2 car garage "blueprint".

2 and 8 look suspect. They look like factory TRW's and the only way I know to get them that clean is a scotch brite pad on a rotary disk, after which I'm not very interested in them because labor spent was more about appearance than performance.

That said, a "freshened" HO 302 with decent heads is pretty light, and can make decent power for relatively cheap. Finding the mythical 400.00 5.3 LS that makes 500 hp around here is turning out to be a unicorn hunt. The "it only took a cam for 500 hp" is amusing to me because the cam was only 300.00 but the springs and pushrods and supporting cast are another 700.00... and another 500 to tune it. Unless it's an aluminum block, it's not any lighter than a 302.

Not to turn this into a Ford v. Chevy thing - I love Chevy engines. If you're planning to beat on the Chevy boys, be prepared to spend some money on heads/cam/intake. They'll have to do the same thing - and Chevy parts aren't free. The LS does have great heads and a stronger block to start with but it still takes parts to make them really go. Gen 1 SBC's need heads every bit as bad as a SBF.

For 800.00 down here, you can bore a seasoned 302 and put new forged pistons (300) in it with fresh bearings, it might be worth chatting with your local machine shop / rebuilder supply.

I think Skervey's build is on the money for fast for cheap. He's doing an excellent job of documenting it. I'd use it for a recipe to get started. There's a lot of incremental improvements that can be done with the SBF but if the ultimate goal is over 450-500 hp, you may want to look at the LS. I'm not sure how easy it would be to plant even 400 hp in an RX7, suspect it may take suspension money $$ before you run out of motor!

Skervey Reader
March 22, 2015 5:45 p.m.
Beagle wrote: I think Skervey's build is on the money..

Thanks Beagle! I will give you advice that I wish someone would have given to me then I started the build. Just buy a donor car! You will spend less $ if you buy a foxbody with 150k on it then you will if you buy all the pieces one at a time like I am doing. Foxbodys can go for $1200 and up and that gives you almost everything you need. then sell the shell to someone who will take it and drop a 351 in it and go drag racing. With a swap its the little things that kill you. Having a complete motor and drive line would be sooooo much easier. I have spent untold amount of hours doing research trying to figure out what parts work together and what I will need and where to buy it from. With a donor car you know that everything works together and when you go onto rock auto to buy replacement parts you go to one make and one year and its all there. I am all over the place buying parts, it can be a pain.

That's how you need to do it if you want to do the swap fast and for cheap. It wont be the fastest car in the world, you will have a 220hp motor assuming it is stock but that's still better then even the turbo II RX7's when they are stock but on the flip-side you will have a stock SBF so the HP only goes up from there.

If you want to build a high HP motor and a really nice swap do like you have been doing. Find a motor that will give you want you want and go from there buying supporting parts to get you to the end goal.

Either way it will be fun and a pain in the ... but if you are like me and just love the build for the sake of the build then you cant go wrong with any motor setup.

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