usdmholden

Hello, I've been on this site reading and researching while I have been working on my build, and I figured I should start a build thread.

I hope this will not be too much history. I've owned either Fox or SN95 Mustangs nearly continuously since 1989, except for 2008 while I had a Lancer Evolution and 2009 when I had no toy car at all. In 2005 I bought a brand new left over 2004 GTO, but still owned a Fox race car in parallel. Back when I had the GTO I kept thinking how great it would be if the GTO were about 1000 lbs lighter like the Mustang was, but still had the LS1 and six speed, and I lamented over Ford's lousy decision of putting mod motors in land barges.

In summer 2010 I bought a $1400, 1991, 2.3L hatchback with OEM black interior, which was in pretty good condition. I drove the car to work nearly every day until about Feb 2013 when the passenger side motor mount broke. I figured if the motor mount was broken, I might as well put an LS1 and T56 in it while I was working on it, and given that the 82hp 2.3L broke a 3/16" steel motor mount, there must have been some fate involved. And also I had already bought the fbody dropout a couple months earlier anyway.

I figure the LS1 / T56 will get at least as good gas mileage as the 2.3L did but it will increase crankshaft power from about 82 hp to about 400 hp.

usdmholden

I started off by taking a bunch of measurements off the 2.3L before pulling the 2.3L engine and T5 trans. I ended up selling the 2.3L/T5 for $450 and the 2.3L exhaust for $40.

Next I tried dropping the long block with the fbody oil pan in the engine bay using 4.6L motor mounts on a the stock 2.3L k member. The 4.6L motor mounts were a set of cheapo CJPony parts which I bought used off Corral for $30.

However, the 4.6L motor mounts would not work on the stock k member. I was not surprised, I figured I would try it and see what happened. The OEM k member mount pads are too low for the 4.6L motor mounts to contact before the oil pan hits the steering rack. Also, the oil pan hits the stock k member long before the bottom of the oil pan comes close to the steering rack. Unfortunately I do not have a good picture, but it is talked about and pictures are shown here, but they are not my pictures:
https://ls1tech.com/forums/conversio...-k-member.html

At this point I figured I would buy a 4.6L UPR k member and swap it in. However, when I called UPR the sales guy told me my dealer account had no purchases in their records and he could not give me dealer pricing. I was not really surprised at this because frankly the last time I bought anything from UPR on my dealer account was in 2002. Therefore I did the next logical thing and called Maximum Motorsports and bought the entire front end kit.

usdmholden

After test fitting my modified CJ Pony parts solid 4.6L mounts I decided they would be OK and I fit some angle steel to the cut legs and welded it on.

schreurs1

Thats a nice looking fox. Could be one hell of a sleeper

usdmholden

Thanks. It's gotten a little faded over the last three years, but a polish and wax and it would look about the same as the pics again.

MustangLS

iTrader: (5)

Nice progress so far. The car is in pretty good shape considering the age.

krochus

iTrader: (1)

I was able to fabricate a motor mount that allowed me to use a truck pan and the stock k-member and lower motor mounts on my 2.3 fox

usdmholden

I saw those mounts you made in another thread, they look pretty nice.

The truck oil pan is pretty different than the fbody oil pan. The rear sump is farther back and deeper, and also the front section is deeper. The 4.6L k member sets the engine so high in the chassis that I was not able to get the T56 in the trans tunnel at a driveline angle of less than about 6 degrees. The modified the 4.6L motor mounts worked, but they made the driveline angle to steep. With a truck pan I believe it would fit like the fbody pan does, but still the driveline angle would be too much.

I ultimately made my own motor mounts which puts the driveline at about 3 degrees, and I measured / calculated the 2.3L at about 2.9 degrees before I pulled it. Also since I was making mounts I set the engine as far back as I could and dropped it a low as I could. My goal was to get an Edelbrock Pro Flo XT p/n 7140 under the stock hood. As of now the Pro Flo 7140 will fit but I only have about 1/8" clearance between the mockup intake which I built and the hood. For this reason I'm planning to drop the k member .500" with spacers to get more clearance. The engine setback and drop puts my mass center much lower and farther back than with the LS1 in the "stock" position (for lack of a better term) on the 4.6L k member in the fox chassis.

Also in order to set the engine back and down, I had to notch the fbody oil pan, which did not work out so well. See link below if interested. I ordered the new Holley 302-2 pan which should fit, and if it does not, I can space the engine upwards with a washer or two under the motor mounts.
https://ls1tech.com/forums/conversio...ing-notch.html

Also since the engine is far back in the engine bay, I cannot weld the bolts into the motor mounts, because installing the engine at an angle causes the heads to hit the firewall and when that happens I cannot line up the motor mounts bolt with the k member slot. The engine is back as far as it can go without cutting the firewall. The firewall has been hammered back about an inch on the passenger side engine bank to get the engine where it is. Really all this means is I need a wrench on the bolt head while tightening the nut. That's not too hard to accomplish.

usdmholden

I picked up a pair of cheap, used, Pro Mustang 1 7/8" N port headers for an 8.2" deck in a fox chassis. These headers are a Coast High Performance brand and are made by the same guy who makes Accufab headers, as well as some others. I welded on some 1 7/8" flanges and tried them out. Seven of the eight primaries fit adequately on the engine while it was being set up in the k member, however, only three primaries actually fit in the chassis.

I cut them apart and am using them as templates for DIY headers. I bought a 1 7/8 build kit from cone engineering which I have not completed yet.

usdmholden

At one point I calculated that the engine was set back .660" behind where the 4.6 motor mounts placed the engine. However, I'm suspecting that the engine is actually farther back then that and I messed up the calculation. I will have to measure the setback relative to the firewall or radiator support once I get the motor back in.

Since the engine is moved back pretty far, I had to cut the MAP port off the back of the LS1 intake manifold. I don't know if the swap kits require this or not, I pretty much assumed the swap kits do not require it.

usdmholden

Once the MAP port was removed a 51mm diameter freeze plug works adequately to plug the hole. I had to put some dimples in the plug to make the fit an interference fit, a few minutes with a hammer and punch took care of the dimples.

I bonded the freeze plug in with a Loctite adhesive that is supposed to provide about 1500 psi of shear strength when bonding to Nylon. The max operational temp is 180F so I will have to check it after a while and make sure the adhesive is holding up.

Also the MAP port was sanded to roughen up the surface which the adhesive will have to bond to.

usdmholden

For the transmission mount, I modified the stock trans crossmember which came with the car. It's a double hump crossmember which is basically the same on all T5 cars after 1986.

I cut it and welded in material to offset back to the OEM fbody transmission mount on the T56. The material for the rubber mount is just 2" angle steel. The material to dogleg back is 2"x.5" structural channel. I had to heat the channel with the acetylene torch to bend it as shown in the pics, and it is kind of funky looking. However, it's like that because it can clear a 4" dual exhaust and the exhaust tube will only sit below the OEM subframes by about 1". Basically the 4" exhaust would be about the same height as subframe connectors. I only plan to run a 3" exhaust so I should have lots of ground clearance as well as chassis and drivetrain clearance.

Once the modified trans mount was fitting well I boxed the channel and the remaining OEM portions of the cross member with 3/16" plate, so it is now very stiff. The rubber bushings were way too compliant so I replaced them with aluminum bushings, Competition Engineering p/n 3610. I don't have pictures of the bushings or boxed sections yet.

I still need to weld in the subframe connectors and reinforce the OEM trans mounts on the chassis side but that should be relatively simple and I have other stuff I want to get done first.

The trans mount can swing into position from either side, I was pretty happy with it when it was done.

When everything is finalized I'm going to slot the hole for the rubber mount. Right now it is just a hole.

usdmholden

At this point in time I believe I have had the engine in and out about 35 times. When I decided to set the engine back as far as I could, I ran into a problem of not being able to bolt the lift chains to the back of the heads because the chains would hit the firewall and I could not get the engine all the way back for the bolt holes to line up.

When I happened I made a lift plate out of some angle steel. It's 1.5"x1.5"x.125" angle steel. About 10 minutes of setup and about 30 minutes in the milling machine and I had a lift plate.

The bosses are there to offset the chain enough to put the center of the chain link at about the same horizontal location as the center of the valley cover bolts. I wish I had offset the bolt holes for the chain a little more, because in actuality, once I tighten the bolt for the chain, I can no longer get the 10mm socket on the valley bolt to loosen and remove the lift from the engine. Oh well, if I ever make another one I won't make the same mistake.

I'm using a piece of cardboard from an old shipping box sandwiched between the block and the old valley cover seal to keep junk out of the engine.

usdmholden

I had some problems welding my fbody oil pan, because I warped it while I was welding the notch. I've tried fixing it multiple times and basically I have given up. At this point the fbody oil pan is now flat enough, it is about .010" on one side and about .008" on the other side. However, in order to fix the warpage I had to add weld with the TIG to get the pan to shrink near the sealing surface and flatten the sealing surface. Doing this has made it ugly, which I don't really care about, but has also made pinholes in a few places, and when I pressure test it to 100 psi, ithe pinholes start to leak.

usdmholden

I never considered an aftermarket pan until recently because none were really shallow enough in the front, and the only one which was almost shallow enough was the Mast oil pan, but it does not have mounts for the transmission like the OEM pans do.

However, Holley recently released the 302-2 oil pan and I calculated it would most likely fit. If it does not fit as is using the drop motor mounts I built, I believe I can space the engine upwards about .080"-.100" and it will be fine. So I ordered one from Jeg for $330 shipped. It arrived today and I took some pictures.

usdmholden

The fbody windage tray needed to be modified to fit the pickup tube.

This was about 30 seconds with a sawsall and 2 minutes with a half moon file and 10 minutes cleaning the metal shavings off.

usdmholden

The fbody dipstick physically fits but it does not line up with the baffle inside the pan. I need to pick up an LS3 dipstick and tube.

Serioussn95

iTrader: (1)

keep us posted about the headers! This is a big deciding factor for me to go nitrous or turbo. The damn dynatechs are so expensive i cant justify buying them. Ive been trying to find more info on the 351w swap headers but havent found much. Thanks for the pics and the info on the thread!

usdmholden

Will do. There have been lots of swaps using 1 3/4" Mac 351w swap headers with LS flanges welded on. The Macs are pretty cheap used, but I wanted a 1 7/8" primary.

The header build kit is about $400 for everything (bends, collectors, velocity spikes, O2 bungs, etc), and then flanges are about $40-$50, and vband clamps if you choose to use them are another $80-$100 or so. The reality is, Dynatechs are about the same price as DIY built, all said and done. Only problem for me is my engine is dropped in the chassis about 1.85" and the Dynatechs or other off the shelf header will sit much too low. That is really the only reason I'm building my own.

The Pro Mustang / Accufab headers were 1 7/8" and also cheap enough that I gambled on them (and lost).

In my experience from having had both on small block Fords, by the time you build all the nitrous stuff and set up the engine and car to run nitrous, you will be at 90% of the cost of a DIY turbo setup, and then you still have to pay to have the nitrous bottles filled.

I have considered doing a turbo on my car, maybe in a couple years. Right now all I want to do is get it on the road so I can show "the boss" some progress. She's patient and is happy that I have a hobby, but I don't want to spend 100% of my spare time in the garage forever.

usdmholden

One of the many times I have had the engine in the chassis, I bolted the shifter base to the T56 to see how the shifter would work and if I could get everything to fit. At first I planned to just weld on a steel bar and offset the handle forwards, but after doing that and seeing how it shifted, I hated the shifter. The shifter had throws which were about 10-11 inches forwards and back. Also, because of the long forward offset, the **** climbed several inches while pulling the shifter back, and dropped several inches while pushing the shifter forwards.

After realizing I hated the shifter I decided to design and build something better. I used Solidworks (I have my own license because I moonlight and do part time contract mechanical design) and reverse engineered the OEM shifter and modified it to work better for my application.

What I wanted was:
1) Throws that were about 4 inches longitudinally
2) Positive stops
3) No **** climb or drop when shifting
4) Optimal **** placement, or at least placement which was as good as the original T5 location

I figured I would need a mechanism that works alot like the GTO shifters, but moved the shifter handle forwards rather than backwards. What I came up with is this. There is about a 1.8:1 longitudinal motion ratio between the shifter base and the shifter handle. IE the shifter handle moves 10 degrees and the shifter base moves 18 degrees. The lateral motion ratio is still 1:1.

The motion mechanism is basically a spherical rod end which is mounted on a 3/8" bolt which is welded into a bracket which is welded to the OEM shifter base. The rod end is about 4.5" forward of the OEM shifter ball. There are positive stops built into the top C plate and that top C plate allows the spherical rod end to come out should it ever need to be replaced.