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-   -   LT4 Vantage Project (https://www.6speedonline.com/forums/aston-martin/453728-lt4-vantage-project.html)

TripleRLT4Vantage 02-16-2024 03:22 AM

Fascinating to see someone else tackling the same bits.. like de-ja-vu!

I brought Craig’s old Vantage and converted it to dry sump. Obvious majority of the mounts and torque tube shortening already done. Avoided the accessory issues buy converting to wet sump belt line but also had to cut and modify the subframe. I went for a H frame arrangement vs slimmer brace.

Have utilised the OE Dry sump tank, and few engine mods:ATI damper & overdrive pully - Upper pulley - LT5 throttle body- ported supercharger etc.

As mentioned above majority of the can integration is working but would be interested in and solution to the traction control light, can send some can logs over if it’s of any help to you for yours etc.


https://cimg5.ibsrv.net/gimg/www.6sp...e30dd4b6b.jpeg
https://cimg0.ibsrv.net/gimg/www.6sp...c185daf18.jpeg
https://cimg4.ibsrv.net/gimg/www.6sp...f2d46885b.jpeg
https://cimg3.ibsrv.net/gimg/www.6sp...4042b1c8cc.png



Prefurbia 02-16-2024 06:21 AM

We need a Vantage Chevy Conversion Kit
 
I had two Porsche 928's with Chevy V8' using the Renegade conversion kits. The first one we bought for $5K in not too great shape and a rough Chevy motor, painted it Ferrari Fly Yellow and replaced the engine with a Blower Motor (600HP, 600lbs trq) with maybe a total 20K invested, and the other one I did the entire car purchasing a 1987 928 with a bad engine for $8K and redoing everything head to toe, reshaped body, placed cameras for mirrors in the fender gills, widened the car, electric doors, redone entire interior with built-in NAV, and a 450HP Chevy motor - stupid $$$$ spent on that one. With the possibility of an aging Vantage market and the 20,000 Vantages made if the Factory does not support the engines, a Renegade type conversion offering can be quite an attractive alternative. For the average person like me, having a local shop do what your doing and also having a proper 600HP+ engine installed, the V12S's hovering around $100K currently are probably a similar investment.
https://cimg7.ibsrv.net/gimg/www.6sp...a6a40221ad.jpg

Digitalsolo 02-16-2024 07:15 AM


Originally Posted by TripleRLT4Vantage (Post 4937125)
Fascinating to see someone else tackling the same bits.. like de-ja-vu!

I brought Craig’s old Vantage and converted it to dry sump. Obvious majority of the mounts and torque tube shortening already done. Avoided the accessory issues buy converting to wet sump belt line but also had to cut and modify the subframe. I went for a H frame arrangement vs slimmer brace.

Have utilised the OE Dry sump tank, and few engine mods:ATI damper & overdrive pully - Upper pulley - LT5 throttle body- ported supercharger etc.

As mentioned above majority of the can integration is working but would be interested in and solution to the traction control light, can send some can logs over if it’s of any help to you for yours etc.

Hey, great to see you over here. I'd heard Craig sold the car, cool to sync up with the new owner, since we're a rare breed with these. :D

I like your setup on the subframe, that seems like a great solution for strength, might crib that a bit to reinforce mine further. I'll keep you up to date on the traction light, I was able to keep it clear in my testing by sending a specific CAN message that shut it off on the cluster, but we'll see if that works in practice the same as it did in theory. I'm just using an Arduino to manage the CAN conversion/data as the Emerald team never got back to me when I tried to buy one of their units.

I've been making steady progress on my swap, just nothing interesting to share. I ordered up a new camshaft, mostly for the uprated fuel pump lobe, along with some valvetrain reliability bits (trunions, titanium retainers, etc.). I did get my torque tube back from being shortened, so I should have all I need to get the drivetrain in. The only real fab work left is the transmission mounts and getting custom half shafts made to mate the GM inners with the Aston outers. I plan to make a DIY set initially to test with, then have custom ones made out of appropriate metal once I'm sure the fitment is dialed in.

Still mostly on schedule for a late spring shakedown.

Digitalsolo 02-16-2024 07:24 AM


Originally Posted by Prefurbia (Post 4937129)
I had two Porsche 928's with Chevy V8' using the Renegade conversion kits. The first one we bought for $5K in not too great shape and a rough Chevy motor, painted it Ferrari Fly Yellow and replaced the engine with a Blower Motor (600HP, 600lbs trq) with maybe a total 20K invested, and the other one I did the entire car purchasing a 1987 928 with a bad engine for $8K and redoing everything head to toe, reshaped body, placed cameras for mirrors in the fender gills, widened the car, electric doors, redone entire interior with built-in NAV, and a 450HP Chevy motor - stupid $$$$ spent on that one. With the possibility of an aging Vantage market and the 20,000 Vantages made if the Factory does not support the engines, a Renegade type conversion offering can be quite an attractive alternative. For the average person like me, having a local shop do what your doing and also having a proper 600HP+ engine installed, the V12S's hovering around $100K currently are probably a similar investment.

Those Porsches are great, that blower through the hood looks so wrong and so right at the same time!

I think if a kit were to be made to do this, it would need to utilize an adapter for the stock torque tube/trans and a custom clutch setup. Most of the work is in adapting the rest of the driveline. I concur with your numbers on the swap cost. My build will be around $35K dollars in parts. If I was charging labor it'd be at least $15K. Put that on a $40K dollar car and you're dangerously close to nice V12V pricing. I do expect to have more power (I'm aiming for ~700 RWHP) and future drivetrain maintenance is notably cheaper. You could put together a 500 RWHP setup for probably $15K in parts if you were smart about it, but that's a lot of effort/money for not much more than a modded 4.7 gets you.

Prefurbia 02-16-2024 04:18 PM

Since the 4.7 was essentially a Ford product at the time - would a Ford instead of a Chevy motor be closer to a bolt on???

Digitalsolo 02-16-2024 07:25 PM


Originally Posted by Prefurbia (Post 4937154)
Since the 4.7 was essentially a Ford product at the time - would a Ford instead of a Chevy motor be closer to a bolt on???

The V12 is a Ford thing. The 4.3/4.7 are Jaguar AJ-V8 based, so closer to that side.

The equivalent Ford engines to make power like the LS/LT would be the mod motor/Coyote stuff and those are MASSIVE. I've got a built Coyote in a '65 Mustang with some turbos on it and it's a real PITA to deal with, because of the proportions. The GM stuff is just so compact. An early Ford OHC motor (302/289/etc) would fit about the same as a GM V8, but then the power isn't there without big cylinder heads or forced induction that won't be as well packaged as the LS/LT blower motors. The big reason I went this was way was the power vs. weight/packaging (plus I know the GM engines well).

This swap really isn't -that- hard compared to a lot of stuff I've built. But there are a ton of little things to deal with and obviously not a lot of documentation.

Digitalsolo 04-12-2024 11:08 AM

Video status update:


Digitalsolo 04-12-2024 08:01 PM

And another video update:


Matt(inMA) 04-14-2024 10:52 AM

Simply impressive talent!!

Digitalsolo 06-04-2024 06:58 AM

No pictures/video today (I know, I know, will get some soon), but a quick status update on my build.

Plumbing is all fully finished. Supercharger cooling system, engine cooling system, dry sump, oil cooler, A/C system, fuel system, transmission cooler, differential cooler. Oil and fuel systems have been leak tested, I'll pressure/vacuum test the cooling systems soon.

Wiring is mostly finished. I've tied the chassis and engine harness together (it's all done with Deutsch DT, DTM and HDP connectors). The stock Aston fusebox manages everything, and I am utilizing the Aston chassis wiring for most functions as well (DBW pedal wiring, clutch switches (both top and bottom of travel), relay controls, etc.). Clutch switch and start button control starting as normal also.

I was able to start the engine up very briefly yesterday. It won't hold idle/stay running yet, but I expect that's due to a couple of the remaining items on my list, which are:
  1. Fuel pressure sensor (feed line) is acting weird. Need to check the wiring and sensor to see what's wrong.
  2. Fuel pump control module (using the Chevy part here) is also acting weird. Might be related to item 1, might be related to item 3, might be something else. Wiring to it is good and checked and it gets power properly. Will figure it out after the fuel pressure sensor.
  3. Drive by wire pedal needs swapped to the GM unit. The Aston pedal inputs are flip-flopped from the GM and it's less work to put the GM pedal in. Just need to swap harness plugs and build a bracket.
  4. Need to program my CANbus gateway to communicate between the GM ECU and the Aston gauges.
  5. Need to tie in my A/C control CANbus box to take the Aston A/C request and put it on the GM CANbus so that the ECU reads the Aston request.
  6. Need to build an exhaust from the headers to my VAP valvetronic back box.
  7. Still need to get the custom half-shafts made. I have someone lined up for this, just need to get them measured. I've been waiting until I was sure I wouldn't need to drop the whole drivetrain out again (so waiting for the engine to run properly and validate my wiring/plumbing is good).
  8. Need to install poly bushings in the front suspension, then reinstall the suspension. Also waiting on the "don't have to drop the drivetrain again" step to be done. https://static.xx.fbcdn.net/images/e...2/16/1f609.png
  9. Once all of that's done, I need to put the interior back together, modify the front/rear shear plates for clearance in a couple areas, build a boot to seal the shifter, etc.
Still a lot of work to do, but most of the hard stuff is done. I think. Probably.


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