Well it's not really a rod, but my hot rod
I have a mgbgt that is going to get v8 power, So at work I got to thinking, instead of using a 302 powertrain, what about using a 318.
I don't really know much about smallblock stuff tho.
Does any have a good guide to the dimensions and horsepower of a decently built 318
I looked on line and at allpar, but didn't really get a good read on what I wanted.
Can anyone toss me some info? Thanks Mike

I don't have numbers and weights to help you decide.
I do have a story that may help. Back in the 60s the Cobra was a success. They also made the Sunbeam Tiger by stuffing a SBF into an Alpine. Chrysler bought interest in Rootes Group (owners of Sunbean) and imported the Alpines and Tigers here. They really wanted to put a 273-318 into the Tiger, but it was not going to happen. I'd imagine your MGB would run into similar issues.
Yes, you can put almost anything into almost anything, but sometimes it's better to do things the easy(er) way.

http://en.wikipedia.org/wiki/Sunbeam_Tiger
has it a bit wrong. Many Tigers have the Pentstar.

This is a bit better
http://www.conceptcarz.com/vehicle/z7994/Sunbeam-Tiger-MK1.aspx

and this
http://www.rootes-chrysler.co.uk/car-history/history-sunbeam.html

Two things prevented the 318 from fitting into the Sunbeam. Rear mounted distributor and length. SBF is shorter in length and height and has a front distributor.

Maybe a Magnum, which is short than an LA 318, and some sort of coil pack ignition might make it fit, you will need to measure.

How do you figure the Magnum is shorter than the LA smallblock? The accessory drive?

not worried so much about the dizzy in the back, more so about weight length and width.
I'll try to get pics of my other mg i never finished up. It's a gutted car so trimming fenders is no biggie, thanks

Mopar Performance book says a 340 measurements are:
Width
Outside valve cover to outside valve cover 20.5"
Oil pan sump 8.25"
Production manifolds 27.1" (some are narrower then this.)

Length
Bellhousing face to
Front of block (approx) 22"
Center of fan belt 27"
front of fan 31.8"

Height
Bottom of pan to
top of production air cleaner 29"
top of carb 26.5"
top of valve cover 22"
Pan rail to top of valve cover 14.5"

Approx weight 500lbs (about the same as a GM 350)
A 318 should be close to the same measurements.
--------------------------------------------------
Just for the record, a 400: and a (440) : and a [225 slant 6] The book gave no numbers for a Hemi.
Width
Outside valve cover to outside valve cover 22.5" (23.8") [17.3"]
oil pan sump 8,25" (8.25") [-]
Production exhaust manifolds ,some are narrower 26.25" (28.8") [17.3"]

Length bellhousing face to
Front of block 23.4" (23.4") [27.7"]
Center of belt 27.2" (27.2") [28.0"]
Front of fan 32.8" (32.8") [32.3"]

Height bottom of pan to
Top of production air cleaner 29.7" (30.0") [29.6"]
Top of carb 25.5" (26.3") [26.5"]
Top of valve cover 22.2" (23.1) [23.8]
Pan rail to top of valve cover 17" (17.7") [19.7"]

Approx weight: slant 6 400lbs; 400 & 440 600lbs: 426 Hemi 700lbs and the older Hemi is heaver then a 426. Any aluminum added would reduce the weights.

Now, swap that Mopar into your hot rod. Gene

Timing cover and pump are shorter, not sure how much. The LA is definately longer and wider and taller than the SBF.

The SBF has a 1.2" lower deck height but one disadvantage to the Ford is the IEIEIEIE port arrangement of the head tends to put the rearmost driver's side exhaust port close to the firewall and can often be a clearance issue with steering columns and brake boosters.