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The second project took and unexpected turn. Originally I was trying to convert a junked L31 into something equivalent to an L46. I was mainly after the Vortec heads and the OEM roller cam.
This is probably going to be permanently back-burnered as I found someone selling off a performance 400 CID with aluminum heads.
I once had a 400 SBC in another ride and I must say, I do have a very soft spot for them.
Furthermore to get the L31 to work there are so many other things that I’d need to do. Balancing, water pump, intake, connecting rods... too much effing around as one person here on the board would put it.
The person selling the SBC400 is including many additional items: MSD distributor, Holley carb, MSD box... many things I can resell to offset. I don’t need two intakes, for example.
it might be over-cammed for my purposes, but not by much. My plan is to pick the motor up this week. I don’t know how long it will be before I attempt the swap, maybe right away... maybe this winter.
So I decided to take a whack at swapping my tire old Frankenstinian creation for a performance 400. I have no ideas what to expect from the new/used engine.
In preparation I already threw off the intake that looks like it’s too big and wouldn’t fit under my hood anyway. My Edelbrock EPS took its spot.
I also pulled off my water pump and, Bubba strikes again...
I discovered that the bypass was plugged. Not sure what this would have as effect but I have had problems purging the coolant circuit. It has never been working to my satisfaction. Perhaps this is why.
Apologies !!! Long time no update ! Suffice it to say that 2020 is a very unusual year
We were at 'throwing in a 400 SBC mated up to a T5'.
Along the way I ran into a few snags such as a snapped oil pressure line and failing my every-four-years technical inspection twice due to a missing sticker that was not even on 1969 cars... Yes, 2020 is quite the lottery ticket.
The idle is a tick lopey... but I like it . There is enough vacuum to run my power brakes, the headlights and wiper door. That's excellent.
The oil pressure is good. At operating temp I get 35 PSI at idle and close to 70 PSI up in the RPM. The exhaust is clean. The plugs looked clean. I did not check the compression because at this point I am quite sure that this is a freshly built engine.
It gets a tick hot in traffic, but that might be an electric fan setting issue.
It does not like dropping under 1500 RPM, so I am learning to drive it "the way it wants to be drive"
Power is a little inconsistent in the lower RPM. My guess is that I need to tune the ignition timing a bit. The EFI is taking care of the carburetion.
The clutch, I have to be careful with... when I give it some onions, I need to keep my foot 100% off the pedal to make sure it doesn't slip. The low profile clutch kit was supposed to be good to 400 HP/TQ. The clutch disk is nothing special and might not have been the best choice. I'll stick with it for a while.
What did you end up doing for the reverse saftey switch?
Tie it into the brake light switch?
some how create a switch on the rod within the original T-handle?
Last edited by mongoose87; Dec 10, 2020 at 01:19 PM.
What did you end up doing for the neutral saftey switch?
Tie it into the brake light switch?
some how create a switch on the rod within the original T-handle?
Those manual transmission cars did not have a “Neutral Safety Switch”, like an auto transmission car had.
Instead, there was a switch connected to the clutch pedal, that only allowed the engine to be cranked when the clutch pedal was fully depressed.
Those manual transmission cars did not have a “Neutral Safety Switch”, like an auto transmission car had.
Instead, there was a switch connected to the clutch pedal, that only allowed the engine to be cranked when the clutch pedal was fully depressed.
my fault, I meant reverse saftey switch..
trying to see what others did for that
I'm doing an auto to t56 swap, and figuring out how to make this work.
not as much risk with a 5 speed wiring to the brake switch, but i think it would still be cool to retain the t-handle reverse lock out functionality.
haven't seen any kits for this. Only the "dummy" aftermarket handles where the t- handle doesn't do anything
The new cam has arrived. I decided to go with a roller cam. My goal here is to match or slightly exceed the L46’s 350 HP and 380 TQ erring on the side of more torque.
This here, installed in my 400 SBC should do the trick.
Dorian, have you determined who made the cam you removed?
"CWC" is CWC Textron, the largest maker of OEM and generic cams and cam blanks. CWC makes the cam shaft blank. It's then sent to the customer for them to grind.
What roller cam are you installing? Solid, Hydraulic? Any spec's on the cam?
I have no idea what cam is in there. All I could determine by measuring is that the intake and exhaust were 0.480 with 1.5 rockers. My rockers are 1.55
The duration and LSA are unknown.
Below is the card of the cam I plan to use. It is a hydraulic roller.
Last edited by DorianC3; Feb 12, 2021 at 11:37 AM.
Sometimes the Our Lady of Blessed Acceleration smiles upon you. I was dreading reinstalling the starter. It was silly easy. I was also worried about the oil pan. It was fairly straightforward as well. I think I should be able to do a test drive tomorrow.
For the one piece gasket I decided to be a guinea pig and NOT add blobs of RTV in the corners for the oil pan install. It says to install dry. Let’s see how well that works. I do like the product.
One issue many members have shown is major vacuum leaks along the China Walls.
Many don’t use any gasket along to wall, but build up a thick bead of silicone, let it set up some and gently set the intake on.
Good luck.
Yes, 2020 is quite the lottery ticket.
. There is enough vacuum to run my power brakes, the headlights and wiper door. That's excellent.
