496 RB on the dyno

[andyf]

Can I ask about your distributor ,ignition system ?

Holley Sniper EFI system with the matching Hyperspark distributor, ignition box and coil. That combination allows me to have complete computer control of the ignition timing. What I found on the dyno is that the engine wants a lot more initial timing than I used to run and it wants a lot of timing while cruising down the freeway. The Holley Sniper setup allows me to program in the timing that the engine wants rather than just giving it what the springs and bushings in the distributor allow it to have.

 

[andyf]

Sounds like a stout engine, should be a lot of fun to play with.

So did you already cut those headers, the Exit looks really high? I'm also looking for a better fitting header, every brand I've seen hangs low including TTI.

Yes the headers have been cut and modified to fit in my car. I need to shorten them a bit and then weld on the rear flange. I have the pipes pretty close to the floor since I don't want the exhaust system to be hanging down below the rockers. I don't like seeing the exhaust system hanging down below a car.

 

[Tim2266ev2]

I'm working on getting the engine ready to go back into the car. Making sure that the headers fit and checking the fit on the starter. I haven't figure out which motor mounts to use yet but I'm leaning towards the big block A body style.
View attachment 740240 View attachment 740241 View attachment 740242

What kind of starter is that?

 

[Andew Sury]

What's the bore and rod length. Well versed in BBC strokers. But not the Mopars. Yet.

 

[andyf]

What's the bore and rod length. Well versed in BBC strokers. But not the Mopars. Yet.

It is a 4.31 bore with 4.25 stroke and 7.100 long rods.

 

[andyf]

What kind of starter is that?

RobbMc

 

[andyf]

Yes the headers have been cut and modified to fit in my car. I need to shorten them a bit and then weld on the rear flange. I have the pipes pretty close to the floor since I don't want the exhaust system to be hanging down below the rockers. I don't like seeing the exhaust system hanging down below a car.

Here is what the headers look like after being modified.

 

[Andew Sury]

It is a 4.31 bore with 4.25 stroke and 7.100 long rods.

Good lord that's a long rod. The BBC is a 6.385

 

[Hemirunner]

Here is what the headers look like after being modified.
View attachment 756720 View attachment 756721

Those are well done. They tuck in nicely.

 

[andyf]

Good lord that's a long rod. The BBC is a 6.385

The Mopar RB block is 3/4 of an inch taller than a BBC so you add the extra distance to the rod. The longer rod keeps the piston further away from the crankshaft and the oil. 7.100 long rods are fairly inexpensive and they seem to be bulletproof at this power level.

 

[andyf]

Working on getting this 496 bolted into my '65 Coronet. I have the transmission crossmember installed so that locates the transmission but I still need to fabricate the motor mounts. I'm using a fixture to hold the engine in the correct location while I fab the brackets. It is a little tough to figure out the correct dimensions so the going is a little slow but I'm getting closer. The Borgeson PS box is in place and the steering column has been rebuilt so things are coming together. The headers seem to clear just fine but we still need to build up the X pipe and mount the mufflers.

 

[557hemi]

I love the fixture, great idea. I’ve used a tool like that too hold up the motor/trans in front wheel drive GMs when pulling the subframe.
Is that left mount bb A body ? The borgeson looks as small as a manual box in there...nice

 

[andyf]

Yes, the LH mount is from a BB A body. It is the only mount that fits since the engine has been moved back as far as it will go. The Borgeson box is small but it still gets in the way a little bit. We had to trim one of the motor mount lugs on the block down for clearance. Typical hot rod project, move one thing and then you have to adjust a bunch of other things.

 

[557hemi]

I’m sure you’re aware or maybe I’m wrong but I think I remember reading you could use a later K in an early B to move the engine back two inches ???

 

[andyf]

I’m sure you’re aware or maybe I’m wrong but I think I remember reading you could use a later K in an early B to move the engine back two inches ???

Yes you can use a later model K frame in an early B body to move the engine back but that isn't what I did with this car. I probably should've tried that trick since it would've solved a bunch of other issues for me but that wasn't the way we built the car. If I was going to start another build like this I'd use a 70 or newer K frame with the anti-sway bar in the K and the double shear idler mount. And then I'd modify the tunnel and transmission mount to make it work. I think that would be less work in the long run but when we built this car we started at the transmission mount and worked our way forward. We had to do it that way at the time but these days I'd do it differently.