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I have a '49 GMC I am putting a 305 in. I am curious as to what motor mount setup to go with. Jim Carter sells a right and left set of brackets that weld to the frame. They are a good couple of dollars but seem to allow access to the oil pan. Everyone else however sells the crossbeam with motor mounts attached that sits between the rail and under the motor. Can anyone recommend one over the other?

I used the crossbeam setup,and it worked out very well. To me it looked a lot easier to line things up and it was an easy install. It made the job of leveling up the engine and tranny much easier. Either setup is just fine,but remember to level and square things up as you go along.

I too went with the crossmember that goes all the way across. For two reasons actually. One was that it's so much easier to locate the motor, and it helps to have it bolted on rather than welded on, because once you have the engine between the frame rails, you need to be able to slide it straight back to engage the transmission's input shaft into the clutch. The other reason is to add frame stiffness.

And being a bolt-in deal, if you ever DO need to pull your oil pan for some reason, you simply support the engine, unbolt the crossmember, and drop your pan.

If you knew how tight it is in there, you wouldn't want a weld-in deal. The frame rails are really too close and that causes problems.

I'm sorry, I have one question about the V8 conversion. If you were going with an engine that made significantly more power than an inline 6, I could understand a V8 conversion. But at 140 hp for a typical stock 305, you stand to gain very minimal power improvement, and may actually lose some torque.
So why go through the trouble to convert if you're not going to step up in power?

Just curious. If the 305 is built for better power, than I totally understand. They are capable of about 330 hp on pump gas when built up. It's just that in stock form, they were very weak.

Actually very simle.. My sixer is 55 yrs old and needs a TOTAL rebuild. The 305 is free, sets me up for a 350 if I should ever want, it has a power steering pump and AC unit, and I plan on scraping the whole torque tube setup. In the end this is to become my everyday driver, not a restoration.

You could use the front fitting second series motor mounts from a 55-59 truck, there's a picture of these mounts fitted on my '50 Chevy truck here. http://i103.piczo.com/view/3/h/b/5/2/u/p/w/0/w/z/t/img/i283585210_46531_5.jpg you just need to put a simple crossmember immediately behind the original one at the front of the chassis. This gives you more space round the motor and more freedom with your exhaust manifolds/header setup than the mid mount setup.

Stuart.

I have read so many times on this site that the 305 is an underpowered motor.The 305s made in the 80s for high performance were definitly not underpowered. I had a 1984 high performance 305 in a 1956 BelAir that would run with just about anything.It left quite a few 350 powered cars sitting in the dust.Seems to me that there are two different 305 motors being discussed here.The 305s made for Camaros,Monte Carlos,Firebirds,etc. were really great performing engines,and not even comparable to an old inline six.

Its safe to say that my 305 is not one of those high power versions. It came out of an 80's Blazer.

The 305 may have felt fast at the time, because Detroit had nothing really any better. But I remember wiping out those 305 Z28's routinely with a turbocharged, 4-cylinder Shelby Charger. They could never keep up.

In later years, when I replaced my 305 with a pump-gas 350 in my '86 IROC, I had a guy in a 5.0 liter Z28 try to race me on one of those great on-ramps that start out two lanes and in about a quarter mile narrow to a single lane, and I remember being about an eighth of a mile ahead of him by the time I merged onto the highway, completely destroying him.

But yes, I do remember when the 3rd gen Camaro first came out with the 305-HO Z28. I rented one in the early 80's to get to the top of a mountain on business in Utah, when they were out of 4WD trucks. This was back in the good days when you actually COULD rent a bonafide sports car with a (gasp) STICK SHIFT!
That was one of the most exhilarating trips I had ever taken in an automobile. The 305 DID feel powerful on that dirt road, and I did a lot of throttle-steering climbing the mountain.

But they still did not make a lot of power. The typical quarter mile times for those was in the 15 to 16 second range. And my Shelby Charger when it was stock, would do a high 14 second quarter. 5.0 Mustangs and Z28's could not keep up with it.

Anyway, back on subject, yes, this will make your truck be able to accept a 350 in the future, which makes total sense. It's also a few hundred pounds lighter than a stovebolt, I believe. That right there will help too.

Actually, the 305 is too big. Find a 3.1" stroke crankshaft from a 262 V-8, and build a small block 255 cubic inch engine. With a set of angle-milled 305 heads with 1.94" intake valves and 1.6" exhausts, plus some porting and polishing and a roller cam, it turns 8,000 RPM and blows away well-built 350's. I build these engines for short-track dirt cars, and with all the externally-visible parts with 305 casting numbers, the competition can't figure out why all they're seeing is the back bumper!
Jerry

Unless you're Grumpy Jenkins, who in the 70's, built a 600 hp 350 small block Chevy which ran 11's in the quarter and destroyed the hot Hemi Mopars at the time. They still haven't forgotten it.

But when you're building a truck, a high winding, low torque small block is probably not the most efficient motor to put in it. Sure, as a race car with super steep gears, why not? But traffic light to traffic light, he's probably not going to like it.

The best-performing 350 I've had on the dyno was also a round track engine,(actually a 355, 350 bored 30 over) made 610 HP at 7,200 RPM. We use the "305" engines in the street stock classes where the 350's are illegal. By using parts with all 305 casting numbers, nobody is willing to risk the high protest fees for anything other than a visual inspection. No, that engine wouldn't be streetable at all!

A 60 over 440 MOPAR made 714 HP on my dyno, at 6500 RPM. It was a tractor pull engine.
Jerry

focus guys; say it with me "motor mounts, motor mounts"

I had an '83 Trans Am with the L69 305, 5-spd and factory 3.73 gears. I added a cheap ($129) Dynomax cat-back, K&N filter, bumped the timing up, and shortened the stock shifter, and I ran a best 14.55 at 99 mph. And this was in 1995. Some of my friends say that it was a "freak." I sure do miss that car.

(Its possible your thread has been stolen.)

Hey I have a 305 out back too. It made horsepower back when it ran...

Are the bolt in crossmember type mounts adequate for a 454 and Turbo 400 in a trailer pulling appication?

I also used the crossbeam setup it worked out sweet It came with the trans crossmember also and it looks awesome too http://rides.webshots.com/photo/2765989600100410726Qopvlq
a little closer shot
http://rides.webshots.com/photo/2170864010100410726zwlBqg
The steering linkage cleared it also but it was kinda tight
http://rides.webshots.com/photo/2690489320100410726AyCvfD
http://rides.webshots.com/photo/2967347810100410726bThvxl

Hope this helps
Todd

Okay, back on the subject I guess.
The crossbeam mount I used from Speedway motors comes longer than you need and you have to cut to fit. That's the tricky part, because I first had to hang the motor in there, attach it to the transmission temporarily, and then I taped off a range as close as I could to where the V8's side mounts begin and end (about 6 inches). Then I pulled the motor out and decided where in that 6 inch range I wanted the crossmember to reside. I chose near the front because of the firewall. Then with my wife standing next to me with the tape measure, I took a piece of wire extended from frame rail to frame rail, then held it up for my wife to measure, and I cut the crossmember a little long, and then ground it until it fit snugly with taps from a rubber mallet.

So yes, I believe this tubular crossbeam motor mount would be robust enough to use for towing duties. It's thick wall tubing.

With a Turbo 400, you have to decide where exactly you want that transmission to reside, based on where the shifter will be in the cab. But others who have used non-original transmissions have been able to move them forward enough for the V8 to clear the firewall. If you use an original tranny, the V8 ends up too close to the firewall, which will then have to be modified for valve cover and distributor clearance. Which sucks.

Then you'll have to locate the tranny mount by some similar method.

A tip, the Speedway motor mount comes with an option of bolting it in or welding it. I definitely recommend bolting it in, because I needed it to move a little when I was trying to get the engine with clutch attached to slide back straight into the transmission's input shaft, and if I welded it in, I would have been screwed. You see, the transmission tunnel isn't tall enough to allow more than about an inch of vertical movement.

You're application with the TH400 will be a little different, but you may find it advantageous not to have that crossmember welded permanently in place also.

Thanks Dad!

The trans is actually going to be a T5 from an 87 Camaro and the rear is from a 78 Firebird. No TH400.

I think the TH400 response was based on the subject correcting question I asked.

As for a reccomendation regarding a crossmember versus the brackets, I think I'd go with the crossmember. I think it will be stronger, and if you look at most cars the small block Chevy has been installed in they generally have a crossmember under the motor in about the same position.

Hopefully, dropping the pan will be a rare thing once the truck is together!

I'd have to measure it, but I'd estimate the bottom of my pan is at least 6 inches away from the crossmember. It may be possible to still drop the pan if you had to. I can't think of too many reasons to, unless you were going to change the rear main seal without removing the engine, difficult but possible; or to change the oil pump.

The T5's a top-loader, isn't it? I'd take some preliminary measurements to the existing shifter hole in the floor of the cab before putting that in there. Because you may end up having to modify your firewall to get the shifter in the right place.

If it was an automatic, the shifter would be on a cable and you could put it anywhere.

I ended up going with the tubular cross member with motor mounts pre welded and now have the motor sitting in the truck. I am a bit bothered though by how low the motor sits. There ends up about 2 in. worth of fan that is below the radiator. I would like to get the fan up higher but to do that I would need to notch the frame to get the crossmember though it, than modify the firewall some. Has anyone else noticed the fan being low? As a note, I am keeping the stock suspension.

I was going to suggest you fabricate your own mounts from some 3/8 ID pipe and some plate. That way you could get the height you need. Now that you have it mounted you will probably find that the distance between the radiator and the mechanical fan is pretty tight especially if you are running the long style water pump. If that is the case then ditching the mechanical fan and using an electric one will be a good option. Going to a short style pump may require you to change all your alternator, Pwr steering and AC bracket setups.

After installing my engine and new radiator I found an interference between the fan blades and the lower radiator hose. I am running an electric fan assembly from a Four Taurus which has two speeds, 2700 CFM and 3200 CFM. I will be wiring the high speed side so it kicks up to that level when the AC is activated.