Stepping up to a Vortec (LM7)

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FluByU said:
Did you reuse the original frame motor mount locations? I have been considering this swap when my F finally gives up and just curious if I can reuse the original mounting location or if they need to move forward or back. Can you post an up close pic as well?

Thanks

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This rig already had a 283 sbc chevy using the AA biscuit style mounts. All I did was buy the AA gen 1 (old school small block) to gen 3 (LSx) adapter plates. I can take pics if you like of the location of the mounts but couldn't tell you if they are forward or backward from the original F/2F location.
 
Badsamaritan,

I see you switched to headers. Did you have a problem with the Corvette manifold? I bought a set, that might not work, blocking the four mounts too much.

Thanks, Ron
 
scrapdaddy said:
Badsamaritan,

I see you switched to headers. Did you have a problem with the Corvette manifold? I bought a set, that might not work, blocking the four mounts too much.

Thanks, Ron
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Ron,

Yup I had the same issue. On the passenger side the manifold flange hit the frame rail. On the drivers side it hit everything, steering shaft, frame rail, etc. I had the C5 corvette manifolds with the O2 bungs built in.
 
Apparently there are the two motor mounts on the block and then you have to use a trans mount on the rear....anyone know who sells the trans mount?
trans mount.webp
 
40's rock said:
Apparently there are the two motor mounts on the block and then you have to use a trans mount on the rear....anyone know who sells the trans mount?
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AA sells the mount in that picture. I have seen it referred to as the "batwing" transfercase mount.
 
JTeeg said:
Lokar makes both a cable and drive by wire pedal that's failry easy to work with.
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It would be pretty spendy to switch to cable at this point. I'd have to get a different ecm/harness/tune as well as the correct throttle body. Probably $800 or so. I looked into the lokar pedals and I believe that they are for the 07 and higher engines. I'm not positive but I don't think I can use one. I talked to speartech and I can use the c5 corvette pedal or any 03-05 truck pedal
 
This may have been suggested, but why not mount the ECU UNDER the glove box?
That's where I have mine an it's not obtrusive, gets plenty of air and also frees the space IN the glove box.
 
chicago said:
This may have been suggested, but why not mount the ECU UNDER the glove box?
That's where I have mine an it's not obtrusive, gets plenty of air and also frees the space IN the glove box.
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The only reason I wasn't sure about the glove box was because I thought my harness would be too short. But in the end everything looks good; I shouldn't have any issue getting it in there.
 
Finally getting to put some more time into this project. Pan swap is complete and torqued down. There is a lot more room between the front DS and the pan now.

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The last few times I have been in the garage I have been working on the clutch slave cylinder. The PO setup hit the new AA headers and was just generally taking up too much space. I tried using the AA bracket that bolts to the back of the bell housing but wasn't able to. The clutch fork is curved so far forward that there would have literally been no pushrod. Since everything is already bolted in place I am going to try what ever I can before I go in and drop the trans and transfer case to change out clutch forks.

In the end I took the PO's bracket and cut it in about half and drilled some new holes for the slave cylinder. I had to take about 1" out of the pushrod but everything looks like it will work. because space is so tight right there I am going to run -3AN lines all the way up to the clutch master cylinder. That way I can do a 90* right off of the slave cylinder. I found a bunch of -3AN to 10x1.0mm fittings on Summit

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I also picked up the Man-A-Fre battery box that mounts to the shock tower for the driver's side since that's where + and - harness cables are. The box is nice, it just doesn't account for much amount of body lift ( I have 2") so I am going to have to make some kind of small bracket so the box can mount to the fender and still reach the shock tower.

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looking good, following this thread like a hawk!

Thanks for all the details and good luck with the rest of the swap.
 
thanks Griffin,

I found some correct firewall grommets on Ebay and cleaned up a few of the holes in the firewall. I ended up pulling the harness back into the cab and cleaning some of up. I still need to re-loom it and then run everything to the correct place.

Also got the hoses and AN fittings I needed to finish the clutch. I'm a little concerned with how close of the fittings is to the header but not much else I can do really. If this ends up not working I'll have to look at using a different clutch fork or going to a hydraulic throwout bearing.
 
I am running the stock H41 trans and was having an issue with the shifter too far forward. Found a cool trick on Mud...use a 60 series trans top....it sets the shifter at the rear and almost exactly into the stock location on my 79 floor pan.
(pic is stolen from Mud)
trans topcover.webp
 
40's rock said:
I am running the stock H41 trans and was having an issue with the shifter too far forward. Found a cool trick on Mud...use a 60 series trans top....it sets the shifter at the rear and almost exactly into the stock location on my 79 floor pan.
(pic is stolen from Mud)
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The problem I was having was with the clutch fork arm. When the PO did the sm420 upgrade he used the stock arm for that trans. With the new engine and the block hugger headers it was all in the way. GM made a cast straight arm that would have been the best option but I already had the engine and trans in. If this new setup doesn't work i'll have to go that route.
 
Sheck44 said:
Wondering whats new, following this closely

Thanks
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I made some progress last night and cut the hole for the harness to pass through the firewall. I may have screwed myself though as I am having a hard time finding a grommet big enough to fit the 3" hole I had to cut to get the pcm connectors and the harness in there. I also tapped the blank port above the oil filter with 1/8-27 NPT threads for my autometer oil pressure sender. I'll try and get some pics uploaded tonight and get this thread caught up with part number's
 
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