Sunny day, building MGB race car can it get any better!

Hello MG Race world,
Just having a tea break whilst building up the new race car, on a sunny day in the UK now that is a first especially over the last week when we have had so much rain im developing web feet! In the picture at last is the un-sung hero of our race car project "The Technical Director" Rob Mason, we have just finished the welding for the solid engine mounts and rear anti-role bar mounts from Dave at FAB-TEK, awaiting the clutch kit and the engine will go back in for the final time! hope the sun stays out for us!

Getting ready for Silverstone? I always make if just for watching the racing.

Did you guys pull the motor back out?

Hi yea to repaint the engine bay lol

Heres are some pics from yesterday of the newly repainted engine bay and the actual dampers installed, the engine/gearbox will go back in this coming tuesday for the final time prior to track testing

Superb, Tom. Are you having this work outsourced, mainly, or are you and your father actively involved in the work? And how about when racing--do you bring someone with you or is it just you two?

Keith/Tom, nice work with the engine mount brackets!:devil:

Don,
All of the work, fabrication, welding ect is done by myself, my father and Rob the only out sourcing was buying the suspension and engine from Dave. All the work is done at my fathers place, where the car is stored. Part of the enjoyment was and still is doing everything ourselves and learning a huge amount along the way.

Certainly doing quite afew race cars before this one has helped but this is meant to be the final all out go at building something a bit special and once it's done the plan is to keep it, race it as much as possible and gradually develop it over the years.

An thanks Dave they work really well, with some suitable pipe connectors the engine should be fairly "quick release" :)

Are those double U-joints at the fire wall on the steering shaft?

If so... the intermediate shaft doesn't look supported.

Steve,

Yea there are 2x UJ joints on the steering shaft, there had to be for everything to fit. Don't worry the long shaft is supported appropriately it just doesn't come across on the pics well.

I think my dad has the same roll bar as you in his car. What brand is it - safety solutions?

Steve, totally agree!

Fred, its a safety devices FIA cage which we have added extra bracing/support too.

Tom, that's it. Awesome!

Beautiful work! Even with all the modifications, I take it this is a vintage car?

James Wiley
SCCA HP Racer

Thanks,
I'm not sure of your exact racing class rules in the US but as far as I know its more of a SCCA style racer than vintage. In the UK the rules for where its going to race are essentially free apart from that it has to use a mgb engine as a base and remain normally aspirated.

Tom

Night shift finally over, weather looks good... well dry at least

Now off to work on the GT, plan for the day is fit the weber, fabricate the new Rad and carb ducting and cut the hole in the bulkhead for the dry sump oil reservoir should be fun :)

Steve, i like the video it does feel like that sometimes

If anything for working on the car today it was too hot, certainly makes a change! lots of progress made though plumbing of the dry sump is very nearly sorted just need a couple more connections. Ducting to the carbs and rad is done just needs bolting in place. The coil packs need wiring into the loom then its windows in, body painted and track test session.

The next pics will be of the car on track for its first on track test session!

Then the fun really begins :)

Tom

(tu)

Thanks Hap that means a lot, if everyones still enjoying the build updates then there will be more pics.

I'd like to share some pics of some of the smaller details I think, inc the window fixings we have planned since you mentioned them. Re the windows our front screen has to be glass the side an rear windows are the thinnest lexan we could legally use.

In a weeks time there is going to be a 3 day marathon of work on the car so there will be lots of pics then.

Tom, on the side rear vent windows, are you allowed to run them in the stock-type open position to let air escape? I've also saw people on GTs put vent holes in the rear glass when you using lexan.

TOM... keep the pictures coming.

Agreed on the pictures. Car looks amazing.

I may have missed it... what color is the GT going to B?

Thanks everyone, the pics will keep coming

Like i said i will try an focus more on some of the small fabrication parts we have done at home

Hap, like the new profile pic BTW, and yes we would be allowed to fit the side windows in an open position or cut vent holes in the rear screen, we may well do that, i like the reasoning behind it.

Steve, the exterior is not my part of the build that is my fathers area of expertise, obviously we both have input in all areas but essentially the running gear suspension etc is my area and the design of the body inc roll cage/lightening/exterior design is down to my father. The body will be British racing green and will include a number of period features you'll have to wait and see for more detail than that!

Thanks again everyone

Just deciding on tires for the race GT, new championship rules mean any tire in the MSA 1a,b list with no restriction in side wall height that means our previous choices of either Yoko A048R 205/60/15 or Dunlop historics are probably no longer the best choice out there.

Were running 15x8 wheels and have pretty big flared arches (as u've seen!)

Any thoughts out there? :)

At present we are considering Toyo's, wider and lower A048's and Goodyears

Thanks!
Tom

I still think the 048's are a great tyre there contact area is bigger than others of same size so you should be able to go wider 225 x 55/50 depending on ratio etc.
Also they are rounder on the shoulder so can fit under the arches ok..

data taken from track driver mag!!

My problem is I can't get any more than 205's under my arches even with max offset on the 15 x 8's

The 048's are better than 888's on most medium weight cars on track days here , the 888's seem to be used more on the caterhams

This free mag has some good stuff on tech
http://subscribe.trackdriver.com/

Progress so far today,

Pics included of the base for the dry sump oil reservoir, this goes in the passenger side foot well.

We have also removed the down plates from the rad ducting so we can remake them, also visible in the other pic is the most forward of the wheel well cut outs these should channel the excess air from around sides of the grill (outside the rad ducting and carb channel) to the wheel wells.

More pics later today!

Some pics of the reservoir base bolted in place

and a pic trying to show the inner wing ducting to promote airflow out of the wheel wells and hence out of the engine bay

Tom, I don't understand what you have done for wheel well ducting. Are these just openings in the fender walls into the wheel wells? Do you also do something to better move air out of the wheel wells?

I also don't understand why you would let any grill air in except to the rad or induction side. It would seems to be an aero-negative without a corresponding gain. What the HELL are you up to, man?:S

Don, if you look at the external contour of fenders on cup cars, you'll see how they use this to pull air out from underhood. This helps when restricted grille inlet air is used to tune downforce. "adding tape made the car loose, pulling tape made the car tight".

If I were going to build another MGB racer with flared fenders, I would attempt to replicate these shapes. I did it a little on my last SCCA car but the fender molds used minimized the effort.

Vintage race rules don't allow this type of aero work.

More baffles and ducting in place, yet to be attached are the side plates, one on the drivers side that will block off the area at the side of the vertical rad divider this is angled to direct more air into the rad "tunnel". The one on the other side surrounds the silver pipe that leads to the carbs and blocks off any air entering the engine bay around the sides of the pipe.

Hahaha Don it will all become clear! there are quite afew more baffles to be added yet! I haven't missed my anti-psychotics today i promise :)

The air gaps i showed earlier today behind the wheels in the wheel well are fairly wide appertures that lead all the way back along the front fenders the air is then ducted in a few directions including a gap between the fender and the door.

Tom, does your carb feed go directly into a closed box which encapsulates the ram tubes on the carb---true ram effect--- or does it just feed cold air to the general carb area?

What I recall from K&N was that induction is optimized by encapsulating the ram tube ends in a race filter which creates a "quiet air" space around the tubes opening. Then the ram tubes can do their job. I recall reading that it was best to direct colder air to the carb area, but not try to ram it in to the box encapsulating the ram tubes. Too much turbulence at the ram tube entrance, which interrupts flow.

Your thoughts?

Don, this is a topic of much debate between me and my father, the decision like most others on the race car will be made over a number of beers and probably a BBQ tomorrow.

The cold air feed from the grill will (if we stay with my current plan!) go to the area close to the Weber/HS6s, with the ram pipes for the Weber enclosed in a filter housing.

We just about finished all the ducting at 9pm tonight after a beer and curry break, i will post some pics tomorrow.

Nice work Tom.

I remember last year Race Car Engineering had a GT2 Porsche in the MIRA wind tunnel. They cut holes at the back of the inner and outer front wheel arch and yielded another 7% front downforce.

The only problem I see with playing with aero at this level is you don't really know what you're starting with. I think I'm right in saying that none of us have access to a wind tunnel so how do we know the aero balance of the standard car? Plus, the modifications made might generate some downforce, or in reality anti-lift, but at what % increase in drag?

The other problem with doing this "too well" ( pun intended re wheel well, thank you) is that the possibility of dynamic imbalance is introduced--high speed oversteer. In his great book about the development of the Porsche 911, Paul Frere recounts that the initial design had too much lift at the front. They added a chin spoiler. But then the rear was too light. They came up with the famous ducktail. In vintage we do not have the option of a ducktail. I do NOT want to go through the kink at Road America with high speed oversteer, and would not want to create any mod which could not be relatively easily undone. The track is our wind tunnel.

More progress today on the engine bay, most of the rad ducting/carb induction is now in place. The biggest task of the day was fitting the dry sump pipe work which is extensive to say the least! The engine bay doesnt look very "MGB" anymore..

The whole project isnt far off now, some tidying to do in the engine bay inc splicing the crank fired ignition into the old loom, windows, paint and suspension set up then track testing >:D<

So the wiring for the new ignition and other engine bay items is now in progress and going well, the brake ducts for the hot weather/short circuit valance are also almost complete (as i said the second air dam/long circuit valance will not have brake ducts) so these have to be removable. Its amazing how long it can take designing and making a few brackets.... After the ducts are connected we can reconnect the brake lines.

So things are going well, we've started thinking about the test sessions now e.g. which circuits to go to, what we want to test and how long..... obviously engine rebuilt time factors in this. We don't want to spend all the run time on testing and then have no time actually left to race it!

We will post some more pics soon of the brake ducts and latest developments

Thanks
Tom

Hello everybody,
As requested some close up detail pics of the work completed today the first pic shows the fabricated front disc cooling pipe ( the other side is a mirror image) and mount which is fed from the front valance, now finished the front valance will be removed and painted with some minor mods to the outer face while its on the work bench prior to final fittng.

The second pic shows the placement of some of the drivers controls, most are plumbed in now except the fuel line and the wiring mods which need finishing, the pic shows from the forward most position on the transmission tunnel firstly the fuel cut off lever then the 2 red T handles to operate fire supresion system and electrical kill switch, next down the line is the brake bias adjustment control and the last item shadowed by the carbon battery box is the hydraulic handbrake control button. The work has been around placement and ease of operation by the driver, final fixing will happen over the next few days with bolt trimming and tidy up. More to follow on the wiring and water plumbing over the next few days.

(tu)

Superb. Now you Brooksmen have to come over here during the 13 season and show us what for.

I do see a couple of points for discussion.

One is cooling to the carb. When I researched this about a year ago I concluded that the optimal Weber configuration was properly-shaped ram tubes encapsulated in the biggest, best race filter I could find. That was a K&N. What I read was that ram effect was maximized if the tube opening was in as much calm, relatively cool air as possible, not fast-moving or disturbed air.

The other is rotor cooling. Initially I will have no ducts in the valence. If I find that I need ducted air to the rotors, I will construct a rotor hat which will capture ducted air and channel it to both sides of the disk. I had this on my '73 BMW 2002, a fluid-boiling nightmare on tight tracks, and it was a worthwhile improvement compared to directing air over one surface.

This is not to quibble, or diminish your fine work. I know that you both seek excellence and love the exchange of ideas, which is why your presence on this forum is so valued.

Don

Don,

You mean a rotor hat similar to the one in the picture below? I have never tried this because we run with the temp stickers and our brake temp is usually pretty low with zero ducting. I have seen this solution used on a lot of competitive bigger, heavier cars so I'm guessing it must work well if you're marginal on brake cooling. The one in the picture below is a Bizzarrini that is regularly entered in the Spa 6 hour race

That's it, Joe. I'm betting on no need for ducting too, and am having a valence built with no holes whatsoever, even for the oil cooler. Sin bravely.

Don

Don, Joe
Great thoughts and comments, the reality with the carb ducting is that we will be testing various air box designs on the track coupled to this supply air feeder so this element is going to be an ongoing trial, we have also the Dave H twin SU set up to play with:S, as with the disc cooling it may not be required as Joe points out in his comments but we have a policy when building race cars that we put it in at the begining, its often less painfull than trying to fit an adaptation when the car is racing and time is short! both ducting elements are planned in to fit with other features so the brackets are all in situ.
There is no weight penalty with the designs, but there could be benefits who knows>:D< thats the fun of building these cars. To be honest it would be fun to see a trans American/Euro series(tu)but in the absence of this dream becomming reality it would be great to see overseas GT race cars on this forum I know you guys like your roadsters but come on there must be more GTs out there to share designs and running data?????????:)-D beer time now!

Just finished a late shift at work 13hrs of well let's say not a lot of fun...

Thanks for the input always v v welcome!

Don, I'd love to bring the car over and see some of you guys one day! One thing my Dad didn't mention but I may have done before is the valance pictured is one of two we will be testing the second is a plain air dam with splitter and only a narrow central gap for flow to the oil cooler. No brake duct holes or brake ducts that's why we went with a simple removable design. As for the carb air supply iv always liked a carb cold air feed but not a ram effect as it were. For the weber we will try a couple of filter an box designs and see what performs best. As my Dad said we also have the twin Headley HIF6s that we plan to compare to the weber and possibly use on bigger circuits they will run with KN cone filters an the cold air feed as pictured.

Thanks for the kind comments too Don!

The work continues at a pace, apart from the wiring work completed we have re-fitted the rear ally seal deck to seperate the driver from fuel, cell next piece of work is to construct the ally shock tower covers which will re-seal the whole area as per MSA regs, these tower sections will be capable of being removed for shock adjustment purposes,
The other pick is of the front valance with its trade mark air intake winglets fitted ,in position and in primer will require a little more work but nealy finished, nice period touch>:D<

Another day another set of issues resolved on the list of "how to build a race car" pics show the laminated screen fitted following several hours work by Rob and myself, we were quoted £125 to fit the screen from a local company! so we had a go ourselves and it looks well tidy!
The second pic shows the new brake pipe brackets we have fabricated and fitted today because the original mounting points no longer exist on our car due to the modifications, the brake system has now been re-built just needs bleeding now.

Well folks last pic for today we have the new front grill we have made from scratch its a works replica using stainless steel mesh and thinned down chrome frame as per the original works grill, all fitted now cannot wait to get the car painted in its works colours, getting ever closer to the finish line and that job list gets shorter!:)-D beer time.

Gosh, it's like tuning into my favorite TV program! I just can't wait for the next episode!
I'm sure you can't either.

Oddly enough, I'm in exactly the same place on my GT. I'm tiddying up all the little details I've added that have to be done before I shoot the basic primer for the paint job I'm doing in....BRG. I shot the intire car in self-itching primer as a guide coat for this stage. I got to admire my efforts in one color (sort of a flat olive green) for about 45 minutes before getting back to work. It's mostly sanded off now with all the little fills I put on the car's 45 years of life.

I've spent two weeks just on the fitment of the Sebring headlight covers alone. I wanted them to fit the headlight buckets like those on a D Jag or a Ferrari GTO. That's meant repositioning the entire headlight assembly a quarter inch down and slightly right or left, depending on the headlight, to get the covers to fit right. And I had to fabricate the little fittings. Then there's the fun of taking two $150.00 light covers and cutting off an inch and a half of material all around each cover and drill 10 holes, all with unerring accuracy.

When I make a mistake on something like this, I'm always reminded of Donald Pleasance in the movie, The Great Escape when he found an error on some German documents he was forging, "That's three days of work up the bloody spout!"

Anyway thanks for sharing!

Keith,

In the photo of the new brake lines... how close is the line to the header?

It might just be an optical delusion, but it looks like the two are very cozy!

Steve, I'll speculate that he'll come back and say at least 2". But good job in pointing that out. Extra eyes are always helpful even from a long distance.:devil:

I think it is an optical illusion. The header does not swing out through the fender well like a lot of V8s and the hydraulic brake pipe is exact where it would be on a street B.

Pretty good movie!
I reposition brake lines on MGB such that they go straight up to the MC, no U bend, no bleeding - bleeds itself. And uses a lot less pipe than stock!

FRM

Hi guys

Don't worry it is an optical illusion, thats the problem with pics

The pipe is actually a fair bit further away than 2" and the bend is much more gradual than it looks like in the pics, thanks though as Dave said extra eyes are always a good thing!

More pics soon i promise glad your enjoying them!

Tom

Technical Update!
Yes folks thanks for the comments we are open to all comments and thoughts, the actual distance is 3" so we think thats enough any thoughts anybody? the bend is more gradual than it looks the "slow bend is something I have always done, I do not like tight angles on pipe work on a race car I do worry about vibration stress and then cracks on sharp angled elements so I have always put in a slow bend/curve to help ease the possible tension at these points. Is this OCD ????? the lines then follow the contours of the inner wing avoiding other elements as the bay is getting rather busy and cramped. The bracket position on the inner wing optimises the travel allowance on the braided brake pipe, to allow for all suspension travel and turning angles, we must have taken two hours to place these brackets:S

Why did you put the windscreen in before you paint the car????? You're going to have to take it out again to before paint!!!!!

Andrew to be honest this car was never going to be a concours show car, the frame was painted around the rubber seal area before it was fitted, we shall now shoot paint up to the seal, it will only have a minimum depth top coat to paint the car, although dont get me wrong the paint finish will be top quality, its still a functional race car as far as we are concerned by the time the Lexan bolt in windows are fitted and the minimum re-fitting of chrome body finishers it will look the part as well as, more importantly go well, hopefully;)

HI Tom,
What ignition system are you using? Sorry if this is a repeat post. Roll cage photos? (tu) Thank you.

To answer Steve's question about "is 2" enough", heat radiating off round surfaces(exhaust pipe) dissipates rapidly with distance. Similarly, heat absorbed by round surfaces is low because very little of the surface is directly facing the heat source. This does not apply to conductive heat transfer.:)-D

Scott,
We are using one of Dave's crank fired ignition systems.

An the email plus the pics you wanted will be on the way tonight!

Tom

Hello everybody, another day, another job list task completed, pics show the internal quick release door mechanisms which has been fitted to both doors, with no internal door structure left this idea was poached from this forum and I have to say works a treat with no weight penalty, the other pic shows the dry sump tank now sealed into the bulkhead, previous pics show the fabricated base stand this shows how we have achieved the sealing of the tank apature to meet regs. The black seals are removable if required for removal of the tank for cleaning, beer time now and watch England thrash Sweden in the Euro football:)-D

Just love the kitchen tiles!!