The 396-6.2 swap project

[gimpyrobb]

NOT a celeb, just an idjit that learns the hard way! It always seems like someone is there to catch me doing things I didn't think anyone would see.

[Barrman]

Well, I haven't been able to schedule a road trip without a trailer yet. I made another thread about how 21 Scouts learned to drive a standard in my M715 last weekend. I did have to drive the truck to the camp out pulling a M101 with the cargo cover on. About 7 miles each way.

The same tank of fuel had me pulling the very heavy Scout trailer against a head wind both ways for 30 miles.

Next weekend I will finally get to do a road trip without a trailer. 190 miles round trip to the Central Texas Airshow. I made a separate thread about that event a week or so ago. Anyway, I topped off the tank yesterday. 10.4 mpg's.

That might not sound too good. However, with the truck idling for about 8 hours straight with the student drivers, driving across pastures, pulling trailers and such. I was pleased. The stock engine would have been around 7-9 and the 396 probably would have been 4-6.

I am also hearing noises I have never heard before. The stock engine had a mess of an exhaust and since I was planning to swap it out from the start, I never really fixed it. The 396 had glass packs when I first put it in and set off car alarms driving through parking lots. I went to turbo style mufflers and it was quieter. Still pretty loud though. The 6.2 has exhaust all the way to the rear and lets me hear things.

Mostly with the NV4500. Every fall when I put the top back on, I would hear noises that I couldn't hear with the top off. I would hear a little bit of gear noise, but not much. Now though, I am getting noise at idle with the clutch out.

My 6.2 had been sitting for a number of years. When I got it running, the idle was at 700 rpm with a warmed up engine. Now that I have around 400 miles on it. The idle has gone up to 850 warmed up. I tried to turn it down yesterday and couldn't get below 720 rpm. The lower the idle, the louder the gear noise from the transmission.

I think the idle won't go down to the 650 it is supposed to be at because of IP timing which is right on the line or because I dumped a gallon of some new in the jug SAE 10 oil somebody gave me the other day. Anyway, that isn't a worry right now.

The NV4500 I pulled out of a 1993 C30 with a 6.5 in it that had thrown a rod. They had just put in a brand new NV4500 before the engine went. It sat in my shop for 3 years before I put it behind the 396. I drained the expensive Syntec oil out and put in a new gallon of the stuff about 5,000 miles ago. Which is probably close to 3 years or more. Then, it sat for 12 months while I did the engine swap.

When the noise got louder after the idle went down yesterday, I checked the fluid level. Something I had not done before because with the shifter removed, I could see there was oil in there. It was fine and clean.

I put a new throw out bearing in with the new engine. Since the noise goes away with pressure on the clutch, I don't think it is the bearing.

I will keep driving and see if it gets worse. If it does, then it looks like I will need a second 700R4 in my life. The first still not found is for the Bomber.

[gonz]

3053a. You know you want it.

[Barrman]

Actually, I do Mark. I just don't want to do the bell housing search again.

[gonz]

That's understandable. I hope some kid wired a couple of washers under your truck instead of the NV going out on you. I was pretty jealous watching the shifting up in Bueno Vista, way WAY smoother than my spicer.

[Barrman]

As I tried to point out in my long post last night. It has always made noise I don't like. I just don't know if it is more now or the same with less noise from everything else?

If it does go out. 700R4 will be the replacement. My CUCV trucks are so much funner to wheel off road with the automatic.

[Warthog]

Tim,

I have two 2wd 700r4s at the shop. Just need a rebuild. Also have two TV cable brackets......

[gonz]

I'm dense and miss the finer points sometimes, lol! My bet is it's the same.

[Barrman]

I put a little over 200 miles on the truck going to and from the air show over the weekend. The main thing learned is that the wind really effects the 6.2.

We drove 90 miles up there into a 20-30 knot head wind. I had to push the entire way to keep above 50 and my goal of 54 cruising didn't happen all that often. The truck ran great, just the wind was killing me. To be fair, the 396 had trouble with head winds in 5th gear too.

The 6.2 was so much more fun at the airshow than the 396. No overheating issues while we staged to be part of the show, no trouble starting because the fuel was bubbling out of the float bowl and the exhaust out the back didn't scare people off like the side pipes did.

I had a lot of people wanting to look under the hood at how everything fit. Saturday, Sermis had his 6.2 powered ambulance there. We had people walking back and forth between them.

Driving home last night we had a 15-20 knot tail wind. I had trouble keeping it below 54 most of the trip. I really could not feel any throttle applied as we just chugged down the road most of the time. As in I would lift and there was just minimal movement at most between cruise throttle and idle. Any hill I wanted to maintain speed on, we did.

I even got pictures with a few more planes. I like this one the best:


I will top off the tank sometime this week and figure out my mpg's. I stayed in a tent instead of the much more comfortable M101 this year just so the 6.2 could have a clean run so I know what to expect fuel use wise. It better be good because that little military surplus tent was small.

[Flingarrows]

I live thos corsairs, awesome plane