Main British Car:
'71 GT rebuild with 3.9 Rover V8
Posted by: Welshie
Date: January 25, 2013 06:14AM
Greetings all, a lot of you have probably seen this on the MGE forum but for those who haven't I thought i'd add it. I'll let the pictures do the talking but this is what i've done so far on my V8 conversion:
My current MGB GT shell is rotten, I've owned it since 2006 and decided its too far gone so i'll be using this new shell to base the rebuild on.Here is the car when purchased (2008) as a rolling shell but lots of spares and already converted to chrome bumper:
The engine bay had been primered over all the dirt and grease!
The wings had been fillered flat, I found out why shortly
Upon removal it seems that this fillering was done as a quick fix to cover some rust. The Ďbeadingí from the wing had rusted to the scuttle so when I removed them it left this damage.
When trying to remove the O/S wing it took me about 30 minutes because it was still seized solid after removing all the bolts. I eventually yanked it off and found that where the upper splash guard had rotted away from the inner wing, they had filled it with builders spray foam that had stuck the wing on! I think this car has been Ďrestoredí by 2 people. The original person who has done a very good job and fitted new castle rails, jacking points, sills etc. Then the guy I bought it from who has tried to shortcut things and filling holes with fiberglass etc! Looking at the shell originally the only welding I expected it to need was a pair of new inner wing upper splash guards, and the triangular section in front of them. As it turns out there were a few more areas that needed minor patching but apart from that the shell was excellent.
Underside as bought.
I originally sourced a 3.5 litre Rover P6 short nose motor that I actually got before buying the shell, but 2 of the bores were rusted out so I scrapped the block but kept all the short nose parts. I will now be fitting a 3.9 engine (see later)
Stripping was easy due to most of the bolts being new (lucky me). The crossbar in the image below I was told was for a soundsystem, but since i've started this restoration i've discovered it is most likely to extend the boot floor and replace the rear seat
First job. I removed the front suspension as a whole, stripped it and cleaned/painted it. Some of the bodges were horrific and had i known I wouldn't have towed the car home. Firstly some of the spring pan bolts had no nuts, and while the 2 anti-roll bar links are new, someone has forced a car wheelnut onto one, cross threading it. The only way to get it off was to drill the nut and of course the arm is useless. Idiots.
Here is the assembly removed from the car.
I've been told that the longer, rubber bumper steering rack mounts can crack when wider tyres and/or more loads are placed on them so I welded gussets to either side of both mounts to give it some better stiffness
Crossmember and suspension parts painted in 2 coats of POR-15 chassis black. Lowered springs were already fitted so i'm also fitting uprated MGB V8 spec bushes.
Next job was to get the shell on a jig and begin the repairs noted above, along with the V8 modifications. This includes extending the height of the transmission tunnel slightly, centralising the fuel tank and making a second lip in the rear valence for the exhausts. I hope to fit a webasto roof but am having trouble finding a frame at the moment and canít afford to pay a fortune for a new one.
After cutting away the worst of the rusty metal over the winter 2010 I finally got a dry day where I was able to get the shell out of the polytunnel to do the much needed grinding, check out the cool shell trolley...
Ground out the remaining metal and spot welds off bother the rusty areas of the inner wings on both sides
And finally cut out the infected areas at the bottom of the A posts. A lot of shaping was needed but I figured it best to cut this out properly so that no rust will spread/come back
Got the repair sections for the wings, and despite them being BMH repair panels they required quite a bit of fettling to fit. Before fitting I sprayed them with Zinc Rich Weld Thru primer then seam sealed them with seam sealer.
Fitment plate for the remote oil filter fitted to the inner wing
Rear axle painted, I have left the inspection plate as I need to fit the correct CW&P and also an LSD if I can.
The Rover LT77 gearbox that will be fitted is taller and so requires a taller transmission tunnel as i'm sure you all know. It can either be 'dressed' (beaten with a hammer) or I preferred the more professional method of making a taller plate. Many thanks to SImon Austin for his measurements and diagrams on here.
The wings were then fitted to give a guideline to the shape the base of the windscreen repairs, later on I decided to use the donor car wings as they are better.
Thought i'd show you the repair of the base of the A-posts. Dad made up some pattern plates and welded them elaborately
This was the shaping done, initially with fibrofill as its flexible and won't crack.
Cleaned all the underseal from the engine bay and scraped off any non keyed paint
A new wing was put on the car, yet they filled this entire area with fibreglass?! Its been removed and repaired
Got the car on its side and scraped off the loose underseal and paint ready for painting
Have got the engine bay & interior painted, and undersealed the inner wings
Talking of the fuel tank. I removed the said item from my 'donor' car and it turns out its had a stainless steel fabricated tank made that fitted to the original mounting points, result! Its slightly narrower than the standard tank but this works out perfectly for clearance with my twin exhaust pipe layout. I'll scrape the poorly keyed paint off the tank and may or may not re coat it. When using the car over the last 4 years fuel capacity was good so i have no worries there.
A post repairs are almost complete, because the wing profiles differ side to side they have been shaped according to each wing being fitted
Reached a milestone on Saturday 24th September 2010. The rebuild of the car began!
I finished painting the underside with underseal. I used Schutz as its plyable but also a LOT cheaper than POR-15
I found that if you 'stipple' it with the brush it removes any brush marks and looks more professional
Engine bay with the crossmember and steering rack fitted
Front suspension built up
Project V8 rolling! Front and rear suspension and the steering fitted so I took dad out for lunch to celebrate :D
While work was stagnant I had a go at the heater. I also found out the bulkhead where the heater pipes connect to has been cut away on me new shell so a new plate needed to be made along with finishing off centralising the fuel tank and repairing some rear valence rust before respraying the shell. I also decided on the colour, Dark British Racing Green.
Aside from that I got the heater back together. Using a new seal kit from Brown & Gammons I also perfected my spraying technique and for the first time I did a good job. I painted the inside white to reflect heat and I flushed out the matrix before refitting. Instead of buying new clips i sandblasted the old ones and sprayed them gold, i'm pretty pleased with the results.
I sliced my thumb open doing work on my brothers Alfa so wasn't best impressed, but got the MG over the pit to finish the welding.
I modified the bump stops for the lower ride height by cutting and welding them together, removing the aluminium spacer. I have a source for stainless steel bolts now so replaced some of the old bolts and it looks much nicer.
This shows the final part of welding that needed doing. The rear corner had some rust and at the same time dad did the modifications to centralise the fuel tank.
The car kept being moved in and out to make space for other work but finally got the last of the welding done (dad is awesome)
As I mentioned before, someone had cut the heater panel out of the car, is should look like this
So dadm made a repair panel. It had to be made in 3 pieces to fit it in there, the first part
This was replicated the other side before making a cardboard pattern for the main panel
Before a plate was made up
And fitted into the car
Thats been painted now and screwed/bonded in so what was left to do before the painting was centralising the fuel tank. I tried taking the wings off the donor car as they are better but the bottom edge thats normally screwed on has been welded, so they needed grinding (later). Just out of interest as I was stripping my old MGB (the donor car), i've realised how rusty it was, here are some pics.
By April 2012 the welding was done
Rear quarter, seam sealed
Heater bulkhead now fitted. I still need to seal it with sealing compound.
The filler neck for the fuel tank relocated. There was a slight error with this so dad inserted a blank plate with a hole then welded the original fuel filler hole onto that. It gave him some more flexibility with movement along with better strength.
One of the fuel tank tabs had to be cut down to fit too.
All that needed doing then was the welds cleaning up around the light area on that side.
One of the things holding the project up before the respray has been the final shaping of the scuttle where it meets the wing tops. The wings from the donor car looked better than the ones that came with the new shell so I wanted to use them, but they were welded to the sill instead of being attached by the usual self tapping screws. Being in a polytunnel meant we couldn't grind them off so we got a chance to look at them. The drivers side came off with a few small holes drilled, the passenger side was cut as close to the base as possible
Both wings are pretty tidy and more importantly, are unrepaired originals. The others are rubber bumper items with bodged repairs so i'm glad I swapped them. They just need some localised repairs.
Upon removing them, it showed just how far gone the donor car was:
In November I got a new V8 motor, A 3.9 interim jobbie.
Bargain off eBay as it had no picture, but the description was detailed enough I was happy it was good. It had done 90,000 miles in a Range Rover and the guy threw in some extras and delivery too.
I will be using a carburettor so wont be needing the injection system. I want to rebuild it so first job was to strip and check it:
Looking clean so far
Bores are all good :)
Stripped as much as I could over the weekend
The shell is now just about ready to paint but unfortunately the weather is holding it up. I live 100 miles away so only get home a few weekends a month so progress is annoyingly slow. However once it gets painted things should progress much quicker.
Here are some photos of the wing fitment issues. You can see that the wing is being held out slightly but I can't take much more off the scuttle material. Of course when the wings are bolted on they will be held tighter and i;m replacing the lead beading with rubber beading so that will give some more flexibility in fitment etc.
As you can see, the nearside wing needs some scuttle profiling to fit....i'm sure each wing is different!!!
The final bit of shaping work needed will be cleaning up this repair...but I need it out of the tunnel before I can grind that and in the middle of winter in Wales there is zero chance of that.
Now onto the engine, the heads look in good order but need a clean up, I had some spare heads but they are the older 14 bolt versions and these are the 10. So I will probably sell the spares ones I have.
Progress is slow due to the weather at the moment and other work being in the garage, plus my brother has found his shell again so has decided to do work on that instead of the MGB...you very much have to get him in the right mood ;) To keep motivated i;m trying to do trims and things indoors.
Engine looked good though the big-end journals at the back of the engine have some scoring
The accompanying bearings.
Given that further forward you went, the better the bearings were, seems to indicate its been starved of oil a bit maybe at some point. It may be ok but to be sure i'm getting the crank checked and ground if needs be. The shells were the originals so I have oversize to work with.
Looking pretty clean
I've been doing a lot of research on the front timing cover issues. I have a P6 spec cover and seeing as a water pump stud is snapped in it and I think i've damaged it beyond repair I gather my best bet is to get an SD1 front cover, though my brother is still trying to salvage the original
On the left is the cover removed from the 3.9 and on the right is the cover I want to fit.
The block is now cleaned and blasted, and i've rubbed all the mating faces up before it has a final clean. I have found a local machine shop that will balance the crank and flywheel for me, though i've still not gotten a concrete answer on how much mass to remove from the flywheel for road use. I'm also buying gearbox this weekend so the plan is to rebuild the bottom end and fit it with the box into the car so we can line up gearbox mounts and the like in the cold months, and then finish the bodywork when I can get out to the shed without a polar suit.
In the meantime, the car is now officially a V8 :) Got the logbook back recently with the updated details.
In the last week i;ve started looking at the dials as cleaning them up is something motivating I can do indoors. More updates as I go, so enjoy :)
Well, had 6 days at home to play on the B this weekend. Of course there were other distractions so it wasnít all spent on the car but I got a bit done. I got home to boxes of bits
And an LT77 gearbox, complete with the release bearing, arm and gear lever, all for the price you usually just pay for the box! I also lined it up to the engine to check the bellhousing, fits perfectly.
Engine first, here it is with the crank in
This engine came with a crank driven oil pump, and therefore had a thicker timing cover so when my dad and I measured the SD1 cover & pulley with the new crank we expected there to be a gap between the pulley and timing gear. So we fitted everything up and it all marries perfectly, which is a relief
Metal Cloyes adjustable timing gear fitted. There are 3 slots on the crank gear allowing you to use standard or advance/retarded timing. Seeing as the standard 3.9 cam is being used I stuck with standard.
And here it is, the short motor almost fully built up
I have 2 distributors. One from my old 3.5 from a P6, the other from this circa 1993 3.9 and has electronic ignition. Can I use this system on my non fuel injected B or shall I just fit electronic ignition to the older distributor?
The sump and oil pickup are being cleaned and will be fitted next, once the gearbox is cleaned up I will fit them together and to a trial fit in the car. Dad thinks it might be easier to install the engine with no heads but I have one question: Can you install the cylinder heads with block hugger exhausts attached to the engine in situ?
Onto the body. The donor car was put back together and made rolling ready for sale or scrapping
The car has good wheels, and nearly new tyres when I parked it up, so I fitted them to the shell. Its amazing how good a set of wheels cam make a project look isnít it?!
Fitted the brake drums which Iíd painted some time ago
Got the car out for some grinding, as the welds had failed on this part under the rear light
Ground it down and covered it in weld-thru primer ready for dad to weld it
Iíve not done much bodywork before, as my brother and dad are the experts at it. BUT in a bid to get confident with it I had a go on a simple part of the car first, so here is the rear quarter after some spot welding
I painted it to protect it a few months ago
Then I grinded it down.
Onto the shaping! First layer
I then sanded this with 80 grit to get the basic level and shaping, flattened it back again then added a bit more filler to take out any dips
Measuring it with a straight edge after the 3rd levelling off showed two tiny indents which I have put a slim of filler over. Dad tells me filler sinks sometimes so I ran out of time yesterday to finish it off but left this final layer on to harden before I go back in a few weeks to put the skim coat on and flatten it back with wet and dry, for my first attempt Iím very pleased so far:
I also got the floor painted with underseal in the corner that had to be left bare for the above welding, so now Iím just awaiting some padding material then I can paint and fit the fuel tank.
Got some work done on the car today, though or some reason I had a distinct lack of motivation and enthusiasm but I hope the photos are enjoyable and re-motivate me.
Fitted the front calipers that I painted red:
My balanced flywheel is now back from the machinist:
Something that caught me unawares was that the engine mounts fouled against one of the strengthening webs. Seeing as these are the best part of £100 I wouldnt have been impressed had I paid that much for mine.
So I had to grind a bit of each plate away to get the correct clearance. Voila:
I hung them up after this and painted them gloss black. I also found the starter I had from my previous engine, I'll send this off for a recondition.
Thats about it for now, I want to clean and paint the gearbox tomorrow and maybe with get more of the bottom end built up, fingers crossed. I keep telling myself that even a little progress is progress.
Edited 1 time(s). Last edit at 05/09/2013 12:12PM by Welshie.