January 17, 2019, 10:28:00 PM

Author Topic: Supe's NASCARX-7 (SB2.2 swap)  (Read 2987 times)

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #15 on: July 29, 2018, 07:19:31 PM »
Nothing new to report.  Engine made its way to the garage yesterday.  Step one will be pulling the intake to send off to Induction Solutions for the EFI conversion.  I also need to drop the oil pan - it appears it has several broken studs, and I need to figure out what I will need to do for surgery on the pan to make it fit with a Granny's cradle (kickout on the pan won't clear passenger's side motor mount) and clear the rack.  I was going to use a pan from Champ, until I realized that the GM SB2 block does not have dipstick provisions, so a standard pan rail won't seal due to the dipstick kickout.  I may still have to go that option, but would need to weld a piece into the dipstick kickout.  The current pan is a nice Moroso aluminum pan with the external wet sump conversion already plumbed and has a nice billet rail, so I'll make it work if I can.

Have you talked to champ?  they may be able to make you a pan without a dipstick kickout.  It seems like on a lot of their pans that is available just not advertised.  I like the champ pan I have

I did, and they've been surprisingly unhelpful. 

Good news is that there weren't any broken studs, just some sealant that looked like it.  Whatever chassis it was in must not have had adequate clearance, so they welded a few of them up.  It basically uses 6 pan bolts, 4 front, 2 rear.  The pan has a thick ass billet rail, and the gasket showed no evidence of leaking. 

Upon closer look and some measuring, it looks like (big surprise) the rack is going to be the issue.  Because the pan is so wide (it basically goes out to the fuel pump boss), it's going to hit the rack mounts, not just the rack.

Initial assessment has me thinking that I should just raise the entire granny's cradle up about 1/2".  I think this will let me use that pan with no modifications and clear everything.  I'm not running a distributor, so no complications there.  There will need to be some hood adjustments for sure and I'll probably need a new strut tower bar (I probably would have anyways), but those are easy fixes.  I think I'll still have adequate clearance to get at the bellhousing bolts, and the driveline angle shouldn't be too funky to cause problems.  May need a bit of massaging at the front of the trans tunnel to clear the T101a linkage, but that's TBD because it's really tight up there. 

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #16 on: August 05, 2018, 06:44:10 PM »
Did I say 1/2"?  I really meant 1 1/2"... after grinding on the cradle  :banghead:

Turns out my eyeballing was off.  If I shim the entire cradle up, a 2x4 made it perfect.  Unfortunately, this means the bellhousing juuuust kisses the trans tunnel, the trans linkage will juuuuust kiss the trans tunnel, and the headers juuuuuust won't f*cking fit even if I chop them up.

*sigh*

Currently plan is still to shim the entire cradle up - I will fab 4-5 spacers to do so.  Eventually, I will look into a front/mid plate mounting option, but this will be the easiest for the time being.  I am abandoning modifying the old headers, and will fab up a new set of 1 7/8".  I'm not particularly worried about equal lengths, since the car has more power than it will ever need, so it's just a matter of making it fit.  I will likely have to lay the engine back another 2 degrees or so - about 5 degrees total looked ideal, though with EFI and an external oil pump, it's only the u-joints I need to worry about. 


Online digitalsolo

  • Administrator
  • Top Fuel
  • Location: Fort Wayne, IN
  • Posts: 22357
  • View Gallery
    • View Profile
    • LS1FC.com
Re: Supe's Engine Swap Thread
« Reply #17 on: August 05, 2018, 10:02:30 PM »
Giant pain in the ass, but should be SUH-WEET when done!
Blake MF'ing McBride
1988 Mazda RX7 - Turbo LS1/T56/ProEFI/8.8/Not Slow...   sold.
1965 Mustang Coupe - TT Coyote, TR6060, modern brakes/suspension...  project car
2013 Focus ST3 - Stage 1 BPU

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #18 on: August 06, 2018, 09:48:37 AM »
I was debating lowering the rack to not deal with the engine placement issues, but I fear it would f the geometry up too much, even with bump steer spacers on the tie rods.  I contemplating hacking the pan up some more, but the windage screen is basically flush with the pan up front, and the front pan dimensions are comparable to basically any dry sump pan I'd end up using in the future, so may as well just make it work. 

Offline DDv8

Re: Supe's Engine Swap Thread
« Reply #19 on: August 06, 2018, 11:14:27 PM »
Have you looked at lowering the K frame? The steering linkage (wheel to rack) has a bought 1/2" adjustment and changes the rack to steering arm angle is only as much as lowering car the same 1/2 " although tire stays in same location as before.

DD
86fc old school 327, T5, converting to 8.8 tbird

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #20 on: August 07, 2018, 06:54:02 AM »
No, I hadn't!  Might be a good way to net me some extra clearance over raising the engine on its own, especially since the clearance at the trans tunnel is so tight.  Good thought, thanks!

Offline shainiac

Re: Supe's Engine Swap Thread
« Reply #21 on: August 07, 2018, 10:55:37 AM »
Won't lowering the subframe negatively impact roll center? If you keep ride height the same, the control arms are going to be at an even greater upwards angle.
'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

Build Thread      Instagram      Youtube

Offline cool

Re: Supe's Engine Swap Thread
« Reply #22 on: August 07, 2018, 12:05:52 PM »
Any chance a fancy @Phish subframe would help?

Offline Phish

Re: Supe's Engine Swap Thread
« Reply #23 on: August 07, 2018, 01:31:40 PM »
The subframe that i provide keeps the steering rack in the same location as stock.  However, we can lower the rack however much you like in a one off production, but then its the buyers responsibility to figure out all of the angles associated with handling, bumpsteer, steering column,  etc.

Also, we only have an LSx mount version, so to run one for a SBC you would need to purchase the version without mounts, and fab your own mount off of the pad upward to the SBC mounts.   However, this would also give you a clean way to put the motor where you would like in the vehicle.

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #24 on: August 07, 2018, 02:56:48 PM »
Won't lowering the subframe negatively impact roll center? If you keep ride height the same, the control arms are going to be at an even greater upwards angle.

I'm less concerned about roll center than I am Ackerman and bump steer.  The car is oversprung as it is and there's very little perceivable body roll.  Lowering the car 1/2" shouldn't hurt much- I run a very tall tire (275/40r17 or 315/35r17), so the car is barely lowered using the GC Koni setup..

Going to a tube k-member doesn't solve the issue.  If I do one in the future for weight savings, I'll fabricate one myself, but I'd sooner get rid of the rear semi-trailing arm setup than bother with the front K-member. 


Offline Supe

Re: Supe's Engine Swap Thread
« Reply #25 on: August 15, 2018, 08:54:48 AM »
Rack came out last night, and rack mounts have been removed (5 stars for Harbor Freight spot weld cutter).  It looks like I can only go about 1/2"-5/8" lower on the rack without major K-member surgery due to the thickness of the k-member and the depth of the rack, especially the driver's side mount, which will require some relief cuts as it is.

Current plan is to shift the entire rack about 3/16" to the driver's side, which will have the big driver's side mount fully clear the pan, and relocate the passenger side mount as far outboard as I can make fit to clear the other side of the pan.  Alternately, I can slot the cradle holes and shift the motor the same distance towards the passenger side, but am still undecided.  This gets the rack mounts out from under the oil pan, and gains me a good 1/2" of clearance right there.  It may be worth sacrificing the engine location for the sake of not f'ing with the tie rod lengths.

Between those two changes, I will only need to gain about 1/2" elsewhere, with the current plan being to cut and lengthen the Granny's cradle to move the motor mounts up.  This will still give me the clearance I need in the firewall/tunnel area, and will minimize the bump steer issues. 

Anyone know offhand if the Speedway Ford/Pinto style bump steer kit will fit an FC spindle?  It's a 7 degree taper. 

Online digitalsolo

  • Administrator
  • Top Fuel
  • Location: Fort Wayne, IN
  • Posts: 22357
  • View Gallery
    • View Profile
    • LS1FC.com
Re: Supe's Engine Swap Thread
« Reply #26 on: August 15, 2018, 09:50:28 AM »
It fits an FD.  :)
Blake MF'ing McBride
1988 Mazda RX7 - Turbo LS1/T56/ProEFI/8.8/Not Slow...   sold.
1965 Mustang Coupe - TT Coyote, TR6060, modern brakes/suspension...  project car
2013 Focus ST3 - Stage 1 BPU

Offline Supe

Re: Supe's Engine Swap Thread
« Reply #27 on: August 15, 2018, 12:21:07 PM »
Worth the gamble as cheap as they are.  I know Ford stuff has fit other RX7 parts, like the steering U joint splines.  Will just have to make up some 5/8-18 to M12x1.25 tie rod adapters for adjustment.

Offline freeskier7791

Re: Supe's Engine Swap Thread
« Reply #28 on: August 15, 2018, 09:42:04 PM »
Worth the gamble as cheap as they are.  I know Ford stuff has fit other RX7 parts, like the steering U joint splines.  Will just have to make up some 5/8-18 to M12x1.25 tie rod adapters for adjustment.
I believe the 7 degree taper is correct.  You could also drill out the taper and use a long 5/8" bolt

Sent from my SM-G920V using Tapatalk


Online digitalsolo

  • Administrator
  • Top Fuel
  • Location: Fort Wayne, IN
  • Posts: 22357
  • View Gallery
    • View Profile
    • LS1FC.com
Re: Supe's Engine Swap Thread
« Reply #29 on: August 15, 2018, 10:19:20 PM »
I have that kit on my Mustang project.   Obviously re-drill them for safety wire or cotter pins, but it's a nice kit, really.
Blake MF'ing McBride
1988 Mazda RX7 - Turbo LS1/T56/ProEFI/8.8/Not Slow...   sold.
1965 Mustang Coupe - TT Coyote, TR6060, modern brakes/suspension...  project car
2013 Focus ST3 - Stage 1 BPU