Performance Increases in a BGT
Discussion
I am considering uprating my 1979 MG BGT instead of buying a £500 banger (PUG GTI or similar) for club motorsport. The wife is happier with this that addign another car to the fleet with increased tax and insurance costs.
Therefore, what recommendations does anyone have for "Low Cost" performance increases ??
Therefore, what recommendations does anyone have for "Low Cost" performance increases ??
Taking weight out will help, but there is no such thing as low cost performance increases I'm afraid.
Peter's book is a good start, and I'd recommend him for engine work (he builds the Engine for my race car that happens to be: a 4 cylinder MGB GT)
Weight removal and working on the suspension are the first areas, along with refreshing and sorting the brakes out. I race with the standard brake setup - but i use V8 size pads of a special compound. You don't need to buy fancy disks or calipers.
What club motor sport are you thinking of taking part in?
Tony
Peter's book is a good start, and I'd recommend him for engine work (he builds the Engine for my race car that happens to be: a 4 cylinder MGB GT)
Weight removal and working on the suspension are the first areas, along with refreshing and sorting the brakes out. I race with the standard brake setup - but i use V8 size pads of a special compound. You don't need to buy fancy disks or calipers.
What club motor sport are you thinking of taking part in?
Tony
Agree with the latter part about brakes - green stuff pads are fantastic and make a big difference.
The biggest problem with the B series engine is the way it breathes (badly). The cheapest things you can do see a noticeable difference in the power are therefore to improve the breathing so:
a) have the head gas flowed (it's badly designed)
b) fit K+N air filters
c) fit a LCB extractor manifold and freeflow exhaust.
You'll need to tweak or change the needles in the carbs to cope with the better mixture, so a rolling road session would prove of huge benefit here too.
A Peco exhaust will cost you about £90, but it would be worth buying a stainless steel one for £250 knowing it will last for life. The rest will cost about £300.
After that you can start looking at cam changes (don't go above a stage 2) in order to shift the torque to where you can best use it, better distributors (£100 +), electronic ignition (£200 for the gucci version), bigger carbs (£300). A weber adds 5 bhp, but costs you 5mpg, doesn't work too well with a better cam and you'll still need to shell out on a manifold.
£2k will give you a supercharged car, £5k+ will get you a v8 conversion.
The biggest problem with the B series engine is the way it breathes (badly). The cheapest things you can do see a noticeable difference in the power are therefore to improve the breathing so:
a) have the head gas flowed (it's badly designed)
b) fit K+N air filters
c) fit a LCB extractor manifold and freeflow exhaust.
You'll need to tweak or change the needles in the carbs to cope with the better mixture, so a rolling road session would prove of huge benefit here too.
A Peco exhaust will cost you about £90, but it would be worth buying a stainless steel one for £250 knowing it will last for life. The rest will cost about £300.
After that you can start looking at cam changes (don't go above a stage 2) in order to shift the torque to where you can best use it, better distributors (£100 +), electronic ignition (£200 for the gucci version), bigger carbs (£300). A weber adds 5 bhp, but costs you 5mpg, doesn't work too well with a better cam and you'll still need to shell out on a manifold.
£2k will give you a supercharged car, £5k+ will get you a v8 conversion.
The ultimate has got to be a V8- mine was the dogs. Having said that I too reccomend Peter Burgess book - have raced against cars with engines built by him and they were darn good. I would rebuild the engine, change the cam, K&N, uprate the brakes, sort the suspension & shocks, anti-roll bars, diff etc. But first check the rules of any series you want to enter and build the car to the rules
Hello Im new here so please bear with me.
My advice would be go for a V8. The MGB and the rover V8 engine is a marriage made in heaven. Not as thirsty as you might think. A 3.5 will return up to 30mpg on a run.
My car has evolved over the last few years ending up with a 4.6L engine.
here is some footage taken at an action day 9th Sept 06. The car filming is a 2.0L Nova. Quality is quite bad Im afraid. My Green V8 Gt can be seen about half way through. Hope this works.http://video.google.co.uk/videoplay?d
Mark
My advice would be go for a V8. The MGB and the rover V8 engine is a marriage made in heaven. Not as thirsty as you might think. A 3.5 will return up to 30mpg on a run.
My car has evolved over the last few years ending up with a 4.6L engine.
here is some footage taken at an action day 9th Sept 06. The car filming is a 2.0L Nova. Quality is quite bad Im afraid. My Green V8 Gt can be seen about half way through. Hope this works.http://video.google.co.uk/videoplay?d
Mark
As others have already stated, Peter Burgess knows about everything there is to know about these engines. His book is very useful as well. He modified the HRG Derrington crossflow head on my '65 MGB (when Chris Betson of Octarine Services was building the engine) and he also did the jetting etc for the Dellortos once the engine was run in. I'm very pleased with it! So pleased, I'm just about to buy a set of his modified heads for the GT V8
As far as other modifications: get a 3/4" front anti roll bar, it transforms the handling of the car. To improve braking, I'd recommend Mintex 1144 pads and shoes. They work very very well from cold.
Stay away from telescopic shocks as Koni, Spax ... Those just make the ride very harsh without really improving handling (I'm going back to lever arm dampers on my car!). If your car is a rubber bumper model, lowering might improve the handling as well!
As far as other modifications: get a 3/4" front anti roll bar, it transforms the handling of the car. To improve braking, I'd recommend Mintex 1144 pads and shoes. They work very very well from cold.
Stay away from telescopic shocks as Koni, Spax ... Those just make the ride very harsh without really improving handling (I'm going back to lever arm dampers on my car!). If your car is a rubber bumper model, lowering might improve the handling as well!
Before going off the deep end with cross flow heads, V-8 conversions, etc, I would suggest studying the rules carefully for the class you plan to run the car in, then select from what's been mentioned already to go to the max power level you can get to in a particular class.
A lot can be said for just doing improved brake pads, shocks (dampers) if allowed, and some wheels/tires - then get out on track and get some experience. If you are like most you will get a good bit faster as you learn what to do.
All this assumes you don't alrady have experience, if you do, then back to making max power (and braking and handling) within the rules for a particular class.
I would think a V-8 conversion could get right interesting if driven hard on track.
A lot can be said for just doing improved brake pads, shocks (dampers) if allowed, and some wheels/tires - then get out on track and get some experience. If you are like most you will get a good bit faster as you learn what to do.
All this assumes you don't alrady have experience, if you do, then back to making max power (and braking and handling) within the rules for a particular class.
I would think a V-8 conversion could get right interesting if driven hard on track.
Grizzly I run a business in Yorkshire restoring MG's, and I've tuned my own cars for many years, I also do a lot of autotesting, buzz me an email if you get 5 mins and we'll have a natter about some ideas for your car, the good news is you can make a b very competitive on autotests for very little money, in all fairness its the driver that wins it at club level not the car.
But I can certainly point you in the right direction to make it a bit zingier, particularly as its one of the rubber bumper models which I have a lot of experience with!
But I can certainly point you in the right direction to make it a bit zingier, particularly as its one of the rubber bumper models which I have a lot of experience with!
Some advice after more years than I care to remember of running and modifying MGAs and MGBs. Quickest, easiest and cheapest improvements relate to shedding weight by taking off unecessary stuff that is already there - like bumpers. Acceleration is a function of weight and torque, not out and out power. Also when competing, don't forget that you don't need to carry the spare wheel, road atlases, CD collection and kitchen sink with you. Nor a full tank of fuel, but use Optimax or Ultimate in it, not cooking unleaded. It all adds up.
As well as a bigger anti roll bar, and sticking with lever arms, fit poly bushes on the front (but not the back). If the damping on the front end is still too soft, try thicker oil in the dampers. That should cost you well under a hundred quid and give you razor sharp turn in compared to the standard set up. And think about lowering it to chrome bumoper B height. Make sure your brakes, tyres and steering are in tip-top order, otherwise fabulous engine mods just kill you that bit quicker.
As to the engine, free up the inlet breathing with feeflow filters and a 3-2-1 exhaust manifiold (wrapped) and straight-through sysytem which again should be less than a hundred quid. Use decent oils and lubricants and change them regularly - one circuit race or track day decreases their useful life massively.
After that, the faster you want to go, the more it costs you.......
MG Mark
As well as a bigger anti roll bar, and sticking with lever arms, fit poly bushes on the front (but not the back). If the damping on the front end is still too soft, try thicker oil in the dampers. That should cost you well under a hundred quid and give you razor sharp turn in compared to the standard set up. And think about lowering it to chrome bumoper B height. Make sure your brakes, tyres and steering are in tip-top order, otherwise fabulous engine mods just kill you that bit quicker.
As to the engine, free up the inlet breathing with feeflow filters and a 3-2-1 exhaust manifiold (wrapped) and straight-through sysytem which again should be less than a hundred quid. Use decent oils and lubricants and change them regularly - one circuit race or track day decreases their useful life massively.
After that, the faster you want to go, the more it costs you.......
MG Mark
Church of Noise said:
Mark, why wouldn't you advise poly bushes at the rear? Lack of compliance?
I'm also quite interested in ways to lighten the car. Removing the bumpers and going the Sebring valence route is already planned (but not for the very near future)...
I'm also quite interested in ways to lighten the car. Removing the bumpers and going the Sebring valence route is already planned (but not for the very near future)...
Spot on - on the front, together with a decent thickness anti-roll bar, they provide a really nice, very positive feel to the steering and handling; on the rear, the handling becomes stiff, jarring and less predictable in terms of when you are reaching the limit. Other ways of lightening the car depend on how much you want to be able to use the car for normal road use as well. I am assuming that you want to keep the car available for road use as well as having fun racing it. If you do, then you probably need to keep some creature comforts, but you can do away with a lot of interior trim, either permanently or just when you race it; I mentioned earlier about leaving the spare wheel out when racing, the same applies to the passenger seat, rear seat, boot floor cover, and they are all 5-minute jobs to remove, which can be replaced at the end of the day to go home. You can go for big bits like that, and small bits as well - do you need the bonnet prop and boot/tail gate stays or will a stick of wood do? Do you need the heater? It's surprising what you can remove and the weight that it all adds up to, without costing you any money. After that, you really are then doing away with glass windows and winding mechanisms, fitting lighter (i.e. fibre glass or composite) panels, and upping the engine performance.
MG Mark
I've got parabolic springs on the rear of mine - they're a lot springier than normal (technical term that!) which is why you need to fit them with gas shocks (koni in my case) to keep up with the bounce. I fitted fast road poly bushes at the rear just to stiffen it up a little and have no problems with jarring at all. I agree they'd be overkill with normal springs, but they're a revolution in handling / ride compromise with the parabolics.
Hiya,
I don't think that polybushes on the rear shackle affect compliance which is more a factor of the spring and damper.
What they do is keep the rear shackle more upright and help with centering the axle, which tends to wander off to the left otherwise!
I would not fit the poly axle pads though - these will transmit more road noise from the axle to the car.
Chris
I don't think that polybushes on the rear shackle affect compliance which is more a factor of the spring and damper.
What they do is keep the rear shackle more upright and help with centering the axle, which tends to wander off to the left otherwise!
I would not fit the poly axle pads though - these will transmit more road noise from the axle to the car.
Chris
I had the response below from the MGOC:
I would agree with almost all of the aspects that you have mentioned. The only area that I would suggest care should be taken is with the flushing of the oil and water system. The water system can be flushed but you need to ensure that you do not flush the crud in to the radiator and cause a blockage. Regarding the oil system there is a thought that suggests that flushing can disturb sludge that contains metal particles which then start to circulate the oil ways and potentially cause issues with damage/increase wear in the engine.
Any comments anyone ??
Also can anyone recommend a engine flush addative, and a flushing oil to do this in a 2 stage process ??
Andrew
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