hey i recently got my second 93 s13, close to being done with all the body work and ready to start working under the hood, i dont want to be like everyone else and just swap a sr20 into it.. boring. to me its all about being an individual, my uncle recently came across a 350 small block and it stuck in my mind and im definetly wanting to swap it, i know i have to fabricate my own motor mounts and that i have to cut pretty deep into the fire wall, but i know that cant be it and that it doesnt just fit well in there, can any of you mad scientists help me out or even throw a parts list i might need, i'd gladly appreciate it

sorry this is a tad long but I want to make sure you have somewhat of an idea about the task it is to push back the firewall and the repercussions.

you don't have to cut the firewall, so far I am the only person I have come across on these forumns that has done that.can use a different pan with the front sump and modify the crossmember.

If you are thinking of cutting the firewall here are the pros and cons.

to start now that my firewall is cut I can only run in e-modified from what I can see in SCCA.

pros-engine sits back nicely helping weight distribution, I used a tko500 transand the shifter is centered in oem location. think the t56 is longer so need to consider having to modify the trans tunnel for shifter if setting motor back. I have a canton road race 7qt oil pan on mine and with a small dent hammered in it sits right behind the steering rack.

cons- have to cut into the main structure at top of firewall because that is where your distributor will go. then you are going to want to reinforce this structure. have to make a custom cover so that rain will not go directly on distributor. the gas pedal mounts to the area that needs to get cut out and pushed back, which means you have to cut off the bottom brackets and make them stick out less so you can mount the pedal with out having it stick out(mine sits about half inch to inch closer still than the brake pedal). only way to keep AC is to pull it and custom mount it in the back seat or trunk. I made the mistake of throwing mine out before realizing I did not need an aftermarket AC. will need to move the passenger side windshield wiper closer to the driver side by a few inches then customize the control arms going from windshield wiper motor to windshield wipers. the passenger side windshield wiper moves right through the location the distributor will end up in. you also need to make the control arm from the windshield wiper to passenger wiper bend around distributor with enough clearance so that it does not start banging on it when you turn them on. if you are planning on running windshield wipers than this is obviously not an issue. being you are in florida though i am assuming you want AC and wipers functional.

I cut my firewall so I could set the motor farther back to make room for my turbo and to help with weight distribution, and to salvage my 300+ dollar pan

at this point I wish I had done the front sump, modded the crossmember, still had AC, and could have used a procharger. would have saved me tons of hours. All the custom work that is required takes too much time.

If you intend for the car to be street legal(legitimately)there is also the issue of smog and engine change laws which you will want to research extensively for your state. there is also the issue of not altering or removing the VIN on the firewall.

having first hand experience with pushing back the firewall I would not recommend it.


Modified by 450SX! at 10:55 PM 3/16/2010

thanks man i really appreciate it do you have any suguestions for tranny and rear end because i know that the rear end i have now will have to come out, any advice i would like as far as getting it running well would be great, thanks.

I am using a 90-95 q45v lsd . the hp you are building for and the driving purpose will depend on what option you should do.

I don't know the details for the other diff swaps but if you search this site there are plenty of options.some I can remember for searches are J30 vsld , s14 vsld, s15vsld , q45 vlsdI think the z32 NA diff works as well as the r32 diff.

if you have any questions about the swap pm me and I will help if i can.


Modified by 450SX! at 7:39 PM 3/17/2010

I would find out if it is a 2 or 4 bolt and have the block sonic tested to make sure it is solid.

thanks man if theres any other heads up you could give me about the swap i'd really appreciate it

McKinney Motorsports makes a kit for swapping a SBC into a 240SX. It includes the engine mounts, transmission mount, and oilpan. And they can also make a custom driveshaft. Above and beyond this, I am not sure what other issues might be encountered with a SBC swap. But if you are not comfortable with fabrication, the McKinney kit might be well worth it.