LT1 swap into a 1991 300ZX

dts300z

Member
Ok here it goes… I have been back and forth with engine swaps in this car for a long time. Since 2003 or so I have done 3 swaps in this car and I have finally made a good choice with the LT1. I actually initially started with the LT1 and then took it out and sold everything off to put away money for a house. I then dropped a turbo 4cyl. In it thinking that would pacify my needs (well that did not last long). So here we are again with the new swap (back to the ole LT1).

The first time I did this swap I really did not plan anything out and pretty much just threw the setup in and wired it up… it turned out pretty shitty to say the least (but it was a lot of fun). So this time I really thought things out and just dove right into a huge project. I first started with tearing out the inside of the car and cutting some big ass holes… lol.

DSC01114-1.jpg

DSC01116.jpg

DSC01117.jpg

DSC01118.jpg

DSC01119.jpg


I got excited after cutting the hole and forgot to take some good pictures so here is the new tunnel in rough stages. I pretty much took a sheet of 16 gauge for the fire wall and cut out a nice radius and tangent legs to wrap underneath the car. Then I used a sheet of 22 gauge to create the tunnel. The 16 gauge piece on the firewall acted as a guide for putting the tunnel in and just kinda fell in place (with a little persuasion of course). Then I broke out the good ole body filler and sander and went to town.

DSC01122.jpg

DSC01123.jpg

DSC01124.jpg

DSC01125.jpg

DSC01128.jpg

DSC01126.jpg


Ahhh amazing what a little bondo and paint does…

DSC01130.jpg

DSC01131.jpg

DSC01132.jpg

DSC01135.jpg

DSC01139.jpg

DSC01140.jpg

DSC01142.jpg


Now its time to fab up some mounts. First thing is first lets see how far back we can shove this engine and center everything up. You have to center everything up tack it in place then build your mounts. Don’t do what I originally did and wedge it in and weld it… lol. Take you time and be sure everything has clearance and nothing will interfere with the engine rocking from torque and settling in place with the new mounts. I’m not a pro just a DIYer so don’t take everything literal. So here are the engine mounts and how the engine sits.

DSC01196.jpg

DSC01197.jpg

DSC01202.jpg

DSC01207.jpg

DSC01206.jpg

DSC01204.jpg

DSC01208.jpg


Here is the tranny mount… kinda beefy. Gotta have reinforcement.

DSC01198.jpg

DSC01201.jpg

DSC01200.jpg

DSC01199.jpg

DSC01203.jpg

DSC01209.jpg


Now you gotta figure out the wiring. Its pretty simple if you do your research. And here is the first fire up. Ohh and don’t forget everything else like exhaust, driveshaft, radiator, fans, fluids, filters, etc….



And when naturally aspiration is not enough you gotta build a home made turbo kit.

DSC01729.jpg

DSC01732.jpg

DSC01768.jpg

DSC01769.jpg

DSC01770.jpg

DSC01771.jpg

DSC01773.jpg

DSC01774.jpg

DSC01775.jpg

DSC01776.jpg

DSC01777.jpg


And this is what happens when you don’t tune the car and just turn up the boost without adjusting the timing on a 130k engine that has overheated a few times due to a bad fan relay… lol. Blown head gasket and broken ring lands on pistons 1 and 3. I heard the detonation on the final dyno pass. I get excited when I start making power and well I’ll turn up the boost until something happens… woops.

http://videos.streetfire.net/video/Turb ... 158121.htm
DSC01781.jpg

DSC01780.jpg

DSC01827.jpg

DSC01826.jpg


Its amazing when you have a ton of time to figure things out cause your broke and you have nothing to do but think of ways to spend the money you don’t have. So instead of just replacing a few pistons and the head gaskets might as well go the distance. Now I’m working on installing a MSII engine management and Ford EDIS-8, injectors, forged pistons ARP hardware and a bunch of other goodies. Here are the pictures of the progress with the EDIS stuff. This is from design to finish.. well almost finished. Here is a good place to get informed about the EDIS stuff. http://www.projectlt10.com/content/modu ... x.php?id=1

triggerwheel-Model.png


This is a bracket a I came up with to hold the VR (variable reluctance) sensor… and it bolts right where the opti used to reside.

DSC02277.jpg

DSC02276.jpg

DSC02272.jpg

DSC02274.jpg


Here is the wheel after getting it back from the EDM. Man it turned out good…

DSC02296.jpg

DSC02297.jpg

DSC02298.jpg


Here is everything mocked up on a timing cover.

DSC02293.jpg


Well I ended up adding a revision to the design. I got a ATI balancer hub and now where I decided to key the factory hub is not going to work with the ATI. So since this happened I decided to make the wheel concentric to the ATI hub to minimize runout. But I still mocked everything back up so I could get everything lined up and ready to go. Although this is not the final 36-1 wheel you can get the idea.

DSC02329.jpg

DSC02328.jpg

DSC02327.jpg

DSC02326.jpg

DSC02325.jpg

DSC02324.jpg

DSC02323.jpg

DSC02322.jpg

DSC02320.jpg

DSC02318.jpg

DSC02317.jpg

DSC02315.jpg

DSC02319.jpg


There will be more to come!!!!

Ok just an update to show you where I’m at… I’ve got some goodies in the mail over the last few months and the engine is going to the machine shop tomorrow. So far I have everything for the bottom end build minus the cam.

DSC02398.jpg

DSC02399.jpg


I’m still waiting on the new 36-1 wheel but I got the new alternator bracket I drew up and it fits pretty well. I still need to wait till I get the engine together to build the spacers to line up the pulley but you get the idea.

DSC02393.jpg

DSC02400.jpg

DSC02402.jpg


I’ve also installed the new shifter… going with an ole turbo 350 to take some stress off the R200 and axles in place of the T56 I previously had.

DSC02405.jpg


I got a wild hair and threw together a side exhaust that exits out of the lower front quarter. I have always wanted to do this… I took an old magnaflow muffler and cut it down to about 8” from its original 12 or so. I took great care not to screw up the packing and overall it turned out great. I revised the engine mounts just a touch centering the engine in the bay within 1/16”. I made the new down pipe to connect to the muffler and cleaned all unnecessary wiring and fuse blocks out of the engine bay. I relocated everything in the car under the dash (easy access). Incase you are wondering about tire clearance between the exhaust there is plenty from lock to lock.

DSC02403.jpg

DSC02409.jpg

DSC02408.jpg

DSC02301.jpg

DSC02302.jpg

DSC02306.jpg

DSC02305.jpg

DSC02300.jpg


This is the block off plate I made for the clutch master.

DSC02418.jpg
 
IVE got to say (HAVING BEEN PERSONALLY INVOLVED IN LOTS OF ENGINE SWAPS) that your skill and ability with a camera is appreciated, ALONG with the effort to document the swap, even before I get into saying IM impressed with the swap and all your work!
DARN IMPRESSIVE --CONGRATS ON A WELL DONE JOB!
the more I look over this post and the photos the more IM impressed with the thought and detail work that went into this
 
Man that thing should flat git with-it!
I like those Z's , and V-8's Like Grump has said Hp to Wt. ;)
How much more does the sbc weigh than the v-6 ? Did you have to do much to the suspension?
I'll be looking for more U-Tube!
Tuck\o/
 
Thanks for the compliments they mean a lot!

Actually I think it was almost a wash when I swaped in the LT1. I put it on corner scales with the LT1 during the 1st attempt at the swap and it weighed in at 2850lbs. Since I have drastically altered the car as far as removing alot of weight from behind the dash and etc... No suspension mods were made and the funny thing is it sits at the same ride height as it did when it was stock.

Dan
 
Alright! So I got the block back from the machine shop along with the rotating assembly and I went to town... I gapped the top rings at 0.025" and the second at 0.024". I plastigauged all the bearings and all the mains were right at 0.0025" across the board and the rods were from 0.0025" - 0.0030". After assembly and torque everything to spec I put a torque wrench on the end of the crank and it took about 25 ft. pounds to start rotating and about 15 or so to keep it going. So far so good!!!

DSC02425.jpg

DSC02426.jpg

DSC02427.jpg

DSC02428.jpg

DSC02429.jpg


Yea I'm kinda a messy builder and I'm very liberal with the moly... lol
 
"After assembly and torque everything to spec I put a torque wrench on the end of the crank and it took about 25 ft. pounds to start rotating and about 15 or so to keep it going. So far so good!!!
Yea I'm kinda a messy builder and I'm very liberal with the moly... lol"

ITS DARN HARD TO GET TOO MUCH MOLY ASSEMBLY LUBE in a new engine assembly and both the clearances and the rotational resistance should be well in spec....looks like your off to good start!
BTW IM STILL VERY IMPRESSED WITH YOUR CAMERA SKILLS
 
Thanks Grumpy! Just a good old Sony Cybershot does the trick... I had the guys at the machine shop check everything out real good and you know you can't be too careful checking them again. Thanks again Grumpy! Your site has been the go to spot for all my unanswered questions about engine building and amongst many other areas around the car. I keep passing along the word too.
 
I keep passing along the word too.
Thanks Grumpy! Just a good old Sony Cybershot does the trick... I had the guys at the machine shop check everything out real good and you know you can't be too careful checking them again. Thanks again Grumpy! Your site has been the go to spot for all my unanswered questions about engine building and amongst many other areas around the car. I keep passing along the word too.

THANK YOU!!!!!!!

BTW heres pictures of a very similar SBC swap /pics of z31 v8 hybrid

z_323.jpg
[/url]
pass. side mount
z_306.jpg
[/url]
drivers side mount
z_305.jpg
[/url]
modified tranny crossmember and custom rubber mount
z_303.jpg
[/url]
pic of mounted tranny
z_105.jpg
[/url]
 
cool!!! I didn't see that one!

Alright I got it idleing good! Here is a little taste of poor quality video at its finest... lol.



BTW Grumpy that cam sounds pretty good!
 
I hooked up the line lock today…

http://www.grandsportregistry.com/lt1vslt4.htm

DSC00217.jpg


I used a main activation switch and 1 switch is for just the front and the other is for both front and rear. I set it up this way to give me better staging and to be able to load the drive train a little better.

DSC00213.jpg


I also installed the tranny cooler and lines.

DSC00214.jpg


DSC00219.jpg


DSC00215.jpg



Lastly I ran into a little snag with the transmission. The aluminum boss crack when I torqued down the front pump… what a bummer and one stripped out. Oh well looking for a new case now.

DSC00220.jpg


DSC00221.jpg


I now have a new hole to fill in the back of the car… lol. I got bored and I couldn’t drive the car so I decided to cut on it instead. Just so you know this was a spare tire well. For the time being I’ll use this gained area for a single muffler with dual tips.

DSC00218.jpg
 
Sorry for the huge delay.

Here are a few pictures with the LS1 coils and a quick video. I still need to work on the tune but it will get there. Also I ran out of electrical tape so the harness is not fully wrapped...



DSC00418.jpg


DSC00419.jpg


DSC00420.jpg



Well one more thing to hold me back just a little bit longer till completion. I have been bouncing back and forth on what I was going to do for the gearing in the rear end. I have finally made a decision and I'm sticking with it... . I have decided to modify the sub frame to accept a 350z differential that so happens to have the perfect gearing (3.35:1) for my tire size I'll be running (26").

So far I have yanked out the sub frame and cut it up a little to make room for the wider footprint between the ears on the 350z diff. As seen below in the comparison picture. You will also notice the the height of the ears are different as well in comparison from the centerline of the pinions and this will also be addressed.

300z on the left and 350z on the right


DSC00234.jpg


DSC00804.jpg


DSC00803.jpg


Here is a pic of the mounting for the new diff.

1114091338.jpg
 
So I stopped at spools-r-us the other day :lol:

DSC00855.jpg


DSC00856.jpg


Yeah I think thats called a lincoln locker.

Here are the pictures from start to finish on the rear subframe modifications. I got real lucky and everything just seemed to fall in place.

I ended up just getting some G35 axles and swapping the ends onto my axles and they seem to work perfect.

DSC00854.jpg


DSC00853.jpg


DSC00852.jpg


DSC00851.jpg


DSC00850.jpg


DSC00849.jpg


DSC00864.jpg


DSC00863.jpg


DSC00863.jpg


DSC00865.jpg


DSC00866.jpg


DSC00861.jpg


DSC00860.jpg


DSC00859.jpg


DSC00867.jpg


DSC00868.jpg


DSC00869.jpg


DSC00870.jpg


DSC00871.jpg


Here are a few pictures of the ducting I'm working on to keep a low pressure under the hood during driving conditions. So far it seems to be working rather well and I'll need to get some more permanent solutions going.

DSC00872.jpg


DSC00873.jpg


I still have alot of tuning to do but I'm thinking over the next few weeks I'll be able to get it up on the dyno and see what kind of numbers we will be working with. I'm shooting for low 500s to the tires on the current setup so keep your fingers crossed.
 
Great pictures.

The bigger something is and the smaller the space you put it in the more complicated it gets.

I recall years ago, a Sprite with an SBC in it.
 
Thanks IBob and Grumpy.

I try to get all the important stuff in the pictures and ask myself "what would I want to see in the pictures and what angles show the most" it seems to work. I really like taking a lot of pictures too because you can really never have too many.

I'm hoping to have some time over the next few weeks to get her up on the dyno, I'm really thinking this thing is going to have some potential. I took it out for a spin yesterday and from a 60mph roll it would just break loose and finally get some traction around 75 or so :lol: . That gear ratio (3.35:1) is a perfect mix for a street and track car with the TH350. I'll be running a 26" ET street on the back at the track.

Edit: I just saw your sig after I posted that :lol: :lol: .
 
Back
Top