Mgb v8 sebring project
Discussion
Hi all,
I have been busy fitting sebring valances, arches and mgc bonnet to my 79 bgt. So far the bodywork is under control so Whilst having a look at the engine options I had a bit of a spontaneous bid on a rover p6 3.5 v8 the other day and won. Turns out it's coming with a auto box from the p6.
So after a bit of reading I now plan to mate it to a lt77 5 speed manual box from an sd1. Any advice on this would be great if anyone has done this before?
I have also read that if I pop in the cam from a 3.9 and sd1 heads then I should get some more bhp. The engine is currently fitted with the classic su set up but seeing as though this will most likely stick out of my bonnet then I plan to change this to a holly carb and have a nice big air filter on show.
It'll rig up to the standard rear axle and see how many tyres I get through with the slightly off diff ratios.
So any tips on this plan? Anything I need to be aware of? Any heads up before I start would be good.
Here is the car currently just to give you an idea of what's going on.
Cheers
I have actually just changed the front valance to a wider one with the winged edges to match up with the arches
I have been busy fitting sebring valances, arches and mgc bonnet to my 79 bgt. So far the bodywork is under control so Whilst having a look at the engine options I had a bit of a spontaneous bid on a rover p6 3.5 v8 the other day and won. Turns out it's coming with a auto box from the p6.
So after a bit of reading I now plan to mate it to a lt77 5 speed manual box from an sd1. Any advice on this would be great if anyone has done this before?
I have also read that if I pop in the cam from a 3.9 and sd1 heads then I should get some more bhp. The engine is currently fitted with the classic su set up but seeing as though this will most likely stick out of my bonnet then I plan to change this to a holly carb and have a nice big air filter on show.
It'll rig up to the standard rear axle and see how many tyres I get through with the slightly off diff ratios.
So any tips on this plan? Anything I need to be aware of? Any heads up before I start would be good.
Here is the car currently just to give you an idea of what's going on.
Cheers
I have actually just changed the front valance to a wider one with the winged edges to match up with the arches
Thanks for all your help Andrew. I have been sanding and priming this weekend so here is another update picture.
I am also powering through the kindle version of how to give your mgb v8 power. It's a great read and a must for anyone attempting the conversion. My budget isn't big and so I am doing all the work myself in my spare time. The body work is getting there and I will get it back on the road with the standard 1.8 in it while I gather the various bits and strip and re build the engine.
I am hoping for somewhere close to 200hp in the end so by not going too fast I can keep the budget down. In a small light car it should be pretty quick.
Still a lot of work to do though but I'll get there. I have never done anything this major to a car before so I am learning as I go. The body has gone alright so far though, it won't be concours but it'll be pretty good.
I am also powering through the kindle version of how to give your mgb v8 power. It's a great read and a must for anyone attempting the conversion. My budget isn't big and so I am doing all the work myself in my spare time. The body work is getting there and I will get it back on the road with the standard 1.8 in it while I gather the various bits and strip and re build the engine.
I am hoping for somewhere close to 200hp in the end so by not going too fast I can keep the budget down. In a small light car it should be pretty quick.
Still a lot of work to do though but I'll get there. I have never done anything this major to a car before so I am learning as I go. The body has gone alright so far though, it won't be concours but it'll be pretty good.
Not added anything to this thread for a while now so thought I would add some pictures, old and new of the mgb. 
Rear bumper fitting. A long time ago now
And arch fitting, had to cut away a lot of the arch. With the rears I had to cut away both outer and inner arch and then weld in some sheet metal to extend the inner arch to meet the new outer. I stopped this half an inch short and then fibreglassed the new metal to the new fiberglass outer arch.
After this a lot of blending started
Rear bumper fitting. A long time ago now
And arch fitting, had to cut away a lot of the arch. With the rears I had to cut away both outer and inner arch and then weld in some sheet metal to extend the inner arch to meet the new outer. I stopped this half an inch short and then fibreglassed the new metal to the new fiberglass outer arch.
After this a lot of blending started
I was having a nightmare with blending the curves and so I glued together sections of hard wall insulation board and the cut and sanded profiles into them with my bandsaw. This made individually shaped sanding blocks for each task. Work speeded up a lot then.
Then I eneded up with the primed car that I posted earlier.
That then turned into this
Then I eneded up with the primed car that I posted earlier.
That then turned into this
Then I had to move it out of my workshop as I got really busy with work so I've moved now, bit more space and a bit more evening painting. So it now looks like this.
I have today lowered the front but I am not sure the banded steels are big enough so I may have to stump up for some alloys soon.
The engine strip down has begun and my piper 270 cam, uprated springs, followers and push rods have arrived. Also some nice air filters and a new uprated alternator. Still got to save up for those rv8 exhust manifolds, wing strengtheners and the rest of the exhaust system. Will try to get it running on the bench first though.
Some progress to report, I spent some time stripping the engine down and dropped off the bits to Barry at T&L engineering. He has acid washed all the parts, honed the bores, ground the crank, fitted the larger Pistons to the con rods. Skimmed the heads, reseated the valves and generally given it all a good going over. The finished result are these bags of goodies 
Today I unpackaged the block and mounted it back on the engine stand. Then I continued stripping the bits off the old engine to pull that out. The exhaust was a bit stubborn and after 45 minuets of struggling I took the reciprocating saw to it and cut the thing off. Very satisfying.
Lovely and clean.
I started this with the intention of not spending loads.... Well it's gone to pot. Engine work cost a fair bit and the shopping list is still long with brakes to buy and exhaust and I'm looking into getting an offenhauser intake and eldebrock or holly carb. Obviously rad as well. Will do a reverse scoop on the bonnet to increase airflow and the rv8 exhaust manifolds through the side of the engine bay.
The necessary addition of larger brakes has meant that I needed to consider larger wheels. Found some on eBay, bought, delivered and now they are on but I'm not sure about them. I like a wider stance with a deep dish but I'll consider that again later on after the engine parts are bought.
Anyway, tomorrow I will start the engine rebuild. Fingers crossed....
Today I unpackaged the block and mounted it back on the engine stand. Then I continued stripping the bits off the old engine to pull that out. The exhaust was a bit stubborn and after 45 minuets of struggling I took the reciprocating saw to it and cut the thing off. Very satisfying.
Lovely and clean.
I started this with the intention of not spending loads.... Well it's gone to pot. Engine work cost a fair bit and the shopping list is still long with brakes to buy and exhaust and I'm looking into getting an offenhauser intake and eldebrock or holly carb. Obviously rad as well. Will do a reverse scoop on the bonnet to increase airflow and the rv8 exhaust manifolds through the side of the engine bay.
The necessary addition of larger brakes has meant that I needed to consider larger wheels. Found some on eBay, bought, delivered and now they are on but I'm not sure about them. I like a wider stance with a deep dish but I'll consider that again later on after the engine parts are bought.
Anyway, tomorrow I will start the engine rebuild. Fingers crossed....
Thanks Andrew. Work has slowed progress massively. Interesting that I started out thinking I'll just stick a v8 in for as cheap as possible and have a bit of fun but when you start all the little bits you start to get anal about things and wanting little bits to be right before you do the next. I'm still not building something as nice as yours but it's certainly going to be a lot better, cleaner and more sorted than the original plan. Taking a while though.
Still checking your thread every now and then and am enjoying seeing the progress. It's looking great.
Still checking your thread every now and then and am enjoying seeing the progress. It's looking great.
Hi Andrew,
They are white 15'' rota grid alloys, actually pretty deep but he curve on the spokes makes them look flatter. I'm not totally sure if I will stick with them but they at least give me the space for some larger brakes when I get them.
Quick question for you if I may (or anyone reading who may have an answer) I have got the block together, crank, pistons (and rings) and cam and it is torqued up to the correct settings. The heads are not on yet and neither is the sump. It is incredibly hard to turn over by hand, was yours like this?
It was impossible to turn with a spanner on the crank nut and do we have to put some of the flywheel bolts in and turn with them using a three foot bar. Even with that its still bloody hard. It seems Far too stiff.
I might be that it is normal because it's got so many pistons but I have no experience with this and so don't want to get too far if it's not right.
All the parts have been either honed or polished and the company that did it supplied the new Pistons, rings, bearings and gaskets for the rebuild so they should all be the correct sizes etc.
I know it's a different engine but though I would ask. Is it normal or do I need to be looking into it further?
Any advice would be great, thanks
They are white 15'' rota grid alloys, actually pretty deep but he curve on the spokes makes them look flatter. I'm not totally sure if I will stick with them but they at least give me the space for some larger brakes when I get them.
Quick question for you if I may (or anyone reading who may have an answer) I have got the block together, crank, pistons (and rings) and cam and it is torqued up to the correct settings. The heads are not on yet and neither is the sump. It is incredibly hard to turn over by hand, was yours like this?
It was impossible to turn with a spanner on the crank nut and do we have to put some of the flywheel bolts in and turn with them using a three foot bar. Even with that its still bloody hard. It seems Far too stiff.
I might be that it is normal because it's got so many pistons but I have no experience with this and so don't want to get too far if it's not right.
All the parts have been either honed or polished and the company that did it supplied the new Pistons, rings, bearings and gaskets for the rebuild so they should all be the correct sizes etc.
I know it's a different engine but though I would ask. Is it normal or do I need to be looking into it further?
Any advice would be great, thanks
Engine all sorted turns now with no problems. I didn't realise there are lobes on the con rods to signify that they are handed and also the bearings are slightly set to one side so basically we had a few of these the wrong way round which resulted in sideways friction on the crank. All sorted now thanks Andrew.
It'll be a carb system, most probably a holly 390cfm with an offenhauser inlet.
Just purchased today the rv8 style exhaust manifolds which I am very excited about. Very immaturely I will fab up some silencers and then route these out just in front of the rear wheels.... Because quite frankly I really want to.
Bit more cleaning etc to do on some other parts.
Lifted the old engine out the other night so some cleaning to do in the engine bay as well.
It'll be a carb system, most probably a holly 390cfm with an offenhauser inlet.
Just purchased today the rv8 style exhaust manifolds which I am very excited about. Very immaturely I will fab up some silencers and then route these out just in front of the rear wheels.... Because quite frankly I really want to.
Bit more cleaning etc to do on some other parts.
Lifted the old engine out the other night so some cleaning to do in the engine bay as well.
Nice video. That's exactly what I'm thinking, sounds amazing. The rods had little directional bulges on the base which I missed to be honest. Plus I was stupidly trying to assemble without a Haynes manual and when your doing it for the first time I guess this is not advisable. Got one now though
Thanks for the comments guys, nice to know that people read it. When I was looking to start all this threads were an invaluable resource as I've never done anything like this before. It's my first attempt at bodywork, bodykits and this much engine work (as you can probably tell). I've fixed my broken cars before but nothing this extreme. Started out with a mk1 cortina and now my daily drive is a 200tdi defender which I had a lot of problems with originally. Learning all the time though.
Flying phil I must say your thread in a huge inspiration to me to just get on and do it. I love a hotrod and it always amazes me that mgbs generally get looked over as a starting point. One day I hope to do a build as extreme as yours. I would love to see it in person one day.
Andrew your thread gives as all something to aim for when it comes to quality and finish.
Anyway I'm still waiting for my exhaust manifolds. U.K. Mail are being crap.
I'm basically just degreasing parts and starting to sort the engine bay. That will go satin black I think as it will give me scope in the future if I fancy changing the colour. Plus the engine bay spray paint from frosts should make it easy.... Hopefully.
Any advice on clutch and flywheel. Should I just get a standard flywheel and have it lightened or buy one that's already done? If that's possible. That is assuming that it's worth while?
Thanks for the comments guys, nice to know that people read it. When I was looking to start all this threads were an invaluable resource as I've never done anything like this before. It's my first attempt at bodywork, bodykits and this much engine work (as you can probably tell). I've fixed my broken cars before but nothing this extreme. Started out with a mk1 cortina and now my daily drive is a 200tdi defender which I had a lot of problems with originally. Learning all the time though.
Flying phil I must say your thread in a huge inspiration to me to just get on and do it. I love a hotrod and it always amazes me that mgbs generally get looked over as a starting point. One day I hope to do a build as extreme as yours. I would love to see it in person one day.
Andrew your thread gives as all something to aim for when it comes to quality and finish.
Anyway I'm still waiting for my exhaust manifolds. U.K. Mail are being crap.
I'm basically just degreasing parts and starting to sort the engine bay. That will go satin black I think as it will give me scope in the future if I fancy changing the colour. Plus the engine bay spray paint from frosts should make it easy.... Hopefully.
Any advice on clutch and flywheel. Should I just get a standard flywheel and have it lightened or buy one that's already done? If that's possible. That is assuming that it's worth while?
1.Rv8 manifolds.
2. I'm not 100% sure I'll stick with the red. I suspect I might have this car for a while. I don't see changing the colour as that big a deal and am thinking in the future I might change it therefore a black engine bay gives me that freedom as I won't need to worry about changing that.
3. The original p6 v8 apparently had 161bhp.
Mine has been skimmed to +.020 so a tiny bit bigger (probably won't make much difference).
It has sd1vienese heads which have very large ports and valves (much larger than the p6 ones) and they have had a light skim.
It has a piper 270 cam which is a fast road cam and piper state gives up to a 24hp increase. Not as harsh as the ultimate road 285 cam.
The rv8 exhaust manifolds should help
The carb will most likely be a Holley 390 with an offenhauser manifold.
All in if I had 180 to 190 bhp I would be very happy but obviously 200 would be the dream.
So with all that in mind I will probably go for the heavier duty 10" one.
4. I'lol take your advice on the bolts. Got to order from real steal anyway. My car will probably be pretty bare so I'm hoping on the low end of the weight scale. Plus a far amount of it is fibreglass anyway really.
I do have an idea of one day just using the whole car a mould and making carbon fibre panels then cutting out and replacing as much as possible with the new bits to make it ultra light. Maybe once I've finished and got bored. But I guess I would be better off doing a space framed project and then doing a while carbon fibre body.
Have you seen this, probably the best mgb project out there.
http://www.speedhunters.com/2014/09/im-sorry-youre...
2. I'm not 100% sure I'll stick with the red. I suspect I might have this car for a while. I don't see changing the colour as that big a deal and am thinking in the future I might change it therefore a black engine bay gives me that freedom as I won't need to worry about changing that.
3. The original p6 v8 apparently had 161bhp.
Mine has been skimmed to +.020 so a tiny bit bigger (probably won't make much difference).
It has sd1vienese heads which have very large ports and valves (much larger than the p6 ones) and they have had a light skim.
It has a piper 270 cam which is a fast road cam and piper state gives up to a 24hp increase. Not as harsh as the ultimate road 285 cam.
The rv8 exhaust manifolds should help
The carb will most likely be a Holley 390 with an offenhauser manifold.
All in if I had 180 to 190 bhp I would be very happy but obviously 200 would be the dream.
So with all that in mind I will probably go for the heavier duty 10" one.
4. I'lol take your advice on the bolts. Got to order from real steal anyway. My car will probably be pretty bare so I'm hoping on the low end of the weight scale. Plus a far amount of it is fibreglass anyway really.
I do have an idea of one day just using the whole car a mould and making carbon fibre panels then cutting out and replacing as much as possible with the new bits to make it ultra light. Maybe once I've finished and got bored. But I guess I would be better off doing a space framed project and then doing a while carbon fibre body.
Have you seen this, probably the best mgb project out there.
http://www.speedhunters.com/2014/09/im-sorry-youre...
It may be a little mad but it's great engineering and I think one of his main aims is that it's all British. I can't help but admire the effort. If he had just dropped an ls in it wouldn't be anywhere near as impressive. It also looks like he's not really got any budget issues. Good on him I say. He may be running close to the wind of insanity but it can take that to make something of real genius.
its been a while since my last post. I have still been gradually getting little bits of the enging sorted. Still have a few jobs to do on it but its getting there.
Here it is so far
All shiney with chrome rocker covers.
I have a super lightweight flywheel from V8 Tuner and full clutch kit to install.
A friend of mine has been helping with the engine build as he has loads of experience with old engines. Here is John gas welding. We had to modify the oil pickup so that it worked with the sd1 sump. John did a great job.
I have also been making progress with cutting the holes for the rv8 exhausts and the lt77 gearbox. Great fun chopping. Soon I will offer the engine and box in for the first time to make sure all of the holes are big enough and in the right places. Fingers crossed.
Today I started to modify the gearbox cross member, and by started I mean chopped the old mounts off and cleaned the thing up. I will be ordering form 10 gauge mild sheet to make the new mounts.
Here it is so far
All shiney with chrome rocker covers.
I have a super lightweight flywheel from V8 Tuner and full clutch kit to install.
A friend of mine has been helping with the engine build as he has loads of experience with old engines. Here is John gas welding. We had to modify the oil pickup so that it worked with the sd1 sump. John did a great job.
I have also been making progress with cutting the holes for the rv8 exhausts and the lt77 gearbox. Great fun chopping. Soon I will offer the engine and box in for the first time to make sure all of the holes are big enough and in the right places. Fingers crossed.
Today I started to modify the gearbox cross member, and by started I mean chopped the old mounts off and cleaned the thing up. I will be ordering form 10 gauge mild sheet to make the new mounts.
Wow that's looking amazing Andrew.
This evening I have won some new wheels on eBay. I wasn't happy with the look of the white rota grid alloys so now I will be trying some rota Rbx wheels, dark grey with a chrome outer. We'll see If they work. Good offset and width for the arches but they may be a little too large in diameter at 17".
Test fitted the engine for the first time the other day, very exciting. I need to enlarge the exhaust holes a bit I think. Very difficult to get in with the bend lower down. I'm not sure of the best method of putting them in. Surely it can't be that they need to go in before the engine? Does anyone know?
Spent two hours today removing the auto pilot bush from the crank. Real pain to get out but done now. Another day of tinkering over.
My engine hoist exploded and shot hydraulic fluid everywhere. A replacement Jack was ordered and now all is working much better.
Will post some pics of the new wheels later in the week.
This evening I have won some new wheels on eBay. I wasn't happy with the look of the white rota grid alloys so now I will be trying some rota Rbx wheels, dark grey with a chrome outer. We'll see If they work. Good offset and width for the arches but they may be a little too large in diameter at 17".
Test fitted the engine for the first time the other day, very exciting. I need to enlarge the exhaust holes a bit I think. Very difficult to get in with the bend lower down. I'm not sure of the best method of putting them in. Surely it can't be that they need to go in before the engine? Does anyone know?
Spent two hours today removing the auto pilot bush from the crank. Real pain to get out but done now. Another day of tinkering over.
My engine hoist exploded and shot hydraulic fluid everywhere. A replacement Jack was ordered and now all is working much better.
Will post some pics of the new wheels later in the week.
Working on the gearbox tunnel recently, lots of cutting. I found it impossible to mark up lying underneath the car to cut the tunnel, nothing worked. Tape wouldn't stick, pens wouldn't show up. I could have cleaned everything off to make masking tape stick but then I had a brain wave, I have laser levels for my day job so was able to fix the beam and set them up to map out the cutting area. Worked great.
After test fitting the engine and box I then turned my attention to making the new raised panel. The result is below, I will weld it on and fine tune it one evening in the week.
I also need to make up the mods for the gearbox crossmember. Mapped out in "how to give your mgb v8 power" (thanks Andrew for suggesting it) I have cut off the old mountings and have marked up the 10 gauge mild steel for cutting ( although it's hard to see in photos)
The holes for the exhaust still need a little enlarging but they'll be there soon
After test fitting the engine and box I then turned my attention to making the new raised panel. The result is below, I will weld it on and fine tune it one evening in the week.
I also need to make up the mods for the gearbox crossmember. Mapped out in "how to give your mgb v8 power" (thanks Andrew for suggesting it) I have cut off the old mountings and have marked up the 10 gauge mild steel for cutting ( although it's hard to see in photos)
The holes for the exhaust still need a little enlarging but they'll be there soon
The hoist Jack luckily wasn't under load when it went Andrew. I was testing it after filling it up with fluid because it wouldn't lift up. I dodged the shooting fluid as it shot past me and hit a wall across the garage. Obviously under a lot of pressure.
I will enlarge the exhaust holes as I can't be doing with the fiddle.
No idea what the tyre profile will be but I am into low cars so I will be modifying the front crossmember a bit and dropping it down. We'll see. I'm on my 4th set of wheels so the tyres will probably change at least a couple of times. I think the wheel look is so important to the overall build that it's worth a bit of buying and selling to get it right.
Practical performance car mag has an article on modding mgb's this month. They are obviously finally getting a bit of cool retro recognition. Not an amazing article but a few nice pics of the John Wilson racing mgb. Very nice race modified, I would love mine to head down a similar direction. It's a bit of a basic look at modifying them. Not quite a flying Phil epic modifying adventure but still good to see.
I will enlarge the exhaust holes as I can't be doing with the fiddle.
No idea what the tyre profile will be but I am into low cars so I will be modifying the front crossmember a bit and dropping it down. We'll see. I'm on my 4th set of wheels so the tyres will probably change at least a couple of times. I think the wheel look is so important to the overall build that it's worth a bit of buying and selling to get it right.
Practical performance car mag has an article on modding mgb's this month. They are obviously finally getting a bit of cool retro recognition. Not an amazing article but a few nice pics of the John Wilson racing mgb. Very nice race modified, I would love mine to head down a similar direction. It's a bit of a basic look at modifying them. Not quite a flying Phil epic modifying adventure but still good to see.
Im after some help,
I cant find a ball cup for my remote selector anywhere unless i buy a whole unit so we are going to make one. Is there anyone out there who has one who is willing to measure theirs for me? I need the lower diameter, upper hole diameter, vertical height and size of the arch but out at the front.
Or if anyone has a spare one that they are willing to sell that would also be great.
Thanks in advance
I cant find a ball cup for my remote selector anywhere unless i buy a whole unit so we are going to make one. Is there anyone out there who has one who is willing to measure theirs for me? I need the lower diameter, upper hole diameter, vertical height and size of the arch but out at the front.
Or if anyone has a spare one that they are willing to sell that would also be great.
Thanks in advance
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