MGExp

MGC Forum

Partial rebuild underway

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

Page 12
Topic List Forum List Newer Older Start New Topic
Partial rebuild underway
#1
  This topic is about my 1969 MG MGC GT
tjh Trevor Howcroft
Edenvale, Gauteng, South Africa   ZAF
Sign in to contact
1969 MG MGC GT
Hi all
The long awaited partial rebuild of my C is now firmly underway and I am finding a few interesting anomalies as I go. One of these is the fact on a UK spec car manual with overdrive there is no angle drive the cable is screwed straight into the gear box. Could this explain a previous post issue where my speedo seems to hopelessly overstate the speed. The needle on the dial is quite steady. Do all UK models have an angle drive and what would be the impact of not having one.

For those interested the engine and Gearbox are out and the engine in the hands of an expert to tear down and do what is necesary. Planning a few tweaks to the motor nothing too intrusive.
- Lighten the flywheel
- Convert head for lead free and gas flow the head.
- Tublar branch exhaust manifold.
- Street CAM to 270 dergrees opening
- Electronic distributor.

Any thoughts and recommendations appreciated.


Thanks all Trevor

Reply
Was this post helpful or interesting?
Yes No Thank
. Become a Supporting Member to hide this ad & support a small business
Re: Partial rebuild underway
#2
jsrivard Avatar
jsrivard Joel Rivard
Riverview, FL, USA   USA
Sign in to contact
1968 MG MGC GT "Maggie"
If I recall correctly when I had the angle drive out and I was spinning it by hand, the ratio seemed to be 1:1 so I don't think that the angle drive introduces any increase or decrease in spinning the cable. I know my non-OD right hand drive manual trans car has an angle drive. The parts catalog does not list an angle drive for the OD transmission, just a "bearing speedometer" which appears to be a straight-through unit.


Cheers,
Joel

MGC "how-to's" available on YouTube:
https://www.youtube.com/playlist?list=PLSuil-nCBffJwKeCv5ZKF02CgPkp1sVvj

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#3
mgcbrian Brian Hutchison
Hampshire, UK   GBR
Sign in to contact
1968 MG MGC
1969 MG MGC
1969 MG MGC
Hello Trevor. No angle drive on UK cars except auto boxes. Brian

Reply
Was this post helpful or interesting?
Yes No Thank
. Become a Supporting Member to hide this ad & support a small business
Re: Partial rebuild underway
#4
kirks-auto Robert Kirk (RIP)
Davenport, IA, USA   USA
Sign in to contact
Most all after market distributors are from China....ALL Lucas replacements are from China. Given your location you may or maynot have a competent service but a rebuilt Lucas original would be my choice given the failures of Chinese goods over the long haul. There are experts in both the UK and USA who can tweek your unit and avoid the mostly unnecessary cost of "no lead head". FWIW, British cars are built to run on just about any sort of petrol found around the world as the world was the market place for these cars and the heads are very well made as OEM units. Valve seat inserts that fail can cause a lot of damage should they fall loose.

270 degrees seems rather aggressive for the street cam and ditto above about where new units are made.


Regards,
Robert Kirk

kirkbrit@yahoo.com
E-mail PLEASE for quote/questions/orders

Business phone 563 323 1017

http://kirks-auto.com/
Moss distributor/UK importer
Beat or match most retail/delivered quote

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#5
JMA Avatar
JMA Silver Member John Anderson
Donvale, Victoria, Australia   AUS
Sign in to contact
1968 Ford Mustang
1969 MG MGC GT
Trevor,

Depending on how you will be driving your car I am agreeing with Robert on the cam.

270° duration is a very aggressive cam, even for me a horsepower tragic. I'm in a similar position to you and currently doing set up for fuel injection, the cam I have chosen is "only" 240° duration and I wouldn't want my cam for a carburettor equipped street engine.

The rest of your list is highly recommended.

John

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#6
kirks-auto Robert Kirk (RIP)
Davenport, IA, USA   USA
Sign in to contact
270 is an all out race cam IMHO and the car will never idle with that duration FWIW. 240 or 250 are street driven cam profiles and 250 still lopes a lot at idle...rather rough.


Regards,
Robert Kirk

kirkbrit@yahoo.com
E-mail PLEASE for quote/questions/orders

Business phone 563 323 1017

http://kirks-auto.com/
Moss distributor/UK importer
Beat or match most retail/delivered quote

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#7
windjammerusn40 Avatar
windjammerusn40 Gold Member windjammerusn40 McCord
East Peoria, IL, USA   USA
Sign in to contact
1968 MG MGC GT
Is that on the trans or on the speedometer? I have a 1968 MGC GT and it has one on the speedometer, although I think that is country (U.S.A.) specific.

Bill

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#8
kirks-auto Robert Kirk (RIP)
Davenport, IA, USA   USA
Sign in to contact
In the USA (NA spec) manual trans have two angle drives...one at each end of the cable.


Regards,
Robert Kirk

kirkbrit@yahoo.com
E-mail PLEASE for quote/questions/orders

Business phone 563 323 1017

http://kirks-auto.com/
Moss distributor/UK importer
Beat or match most retail/delivered quote

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#9
mgcbrian Brian Hutchison
Hampshire, UK   GBR
Sign in to contact
1968 MG MGC
1969 MG MGC
1969 MG MGC
My reference was for UK cars. Just for clarity UK cars don't have an angle drive at the gearbox end or the speedo end either except autos which have it at the gearbox end ONLY.

US cars ALWAYS have it at the speedo end no matter what gearbox but NO angle drive on Overdrive gearboxes at the Gearbox end. Like UK cars US auto cars have an angle drive at the gearbox end. I'm not sure about US manual non overdrive gearboxes. I will have to check it out.

Hope this all helps. Brian.

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#10
jsrivard Avatar
jsrivard Joel Rivard
Riverview, FL, USA   USA
Sign in to contact
1968 MG MGC GT "Maggie"
In reply to # 3700164 by mgcbrian My reference was for UK cars. Just for clarity UK cars don't have an angle drive at the gearbox end or the speedo end either except autos which have it at the gearbox end ONLY.

Are we sure about this? My UK car has an angle drive on the gearbox end. My trans is manual, non-OD.


Cheers,
Joel

MGC "how-to's" available on YouTube:
https://www.youtube.com/playlist?list=PLSuil-nCBffJwKeCv5ZKF02CgPkp1sVvj

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#11
mgcbrian Brian Hutchison
Hampshire, UK   GBR
Sign in to contact
1968 MG MGC
1969 MG MGC
1969 MG MGC
Joel. Yes I think you are right. Will double check today. Brian

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#12
mgcbrian Brian Hutchison
Hampshire, UK   GBR
Sign in to contact
1968 MG MGC
1969 MG MGC
1969 MG MGC
Just checked a manual non overdrive gearbox. Has the angle drive fitted. That means that both US and UK cars have angle drives at the gearbox end for non overdrive boxes. Brian

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#13
chormy Avatar
chormy Gold Member Shaun Holmes
Norwich, Norfolk, UK   GBR
Sign in to contact
1963 MG MGB MkI "3330 PE"
1964 MG MGB MkI
1967 MG MGB GT "BABE"
1967 MG MGC    & more
Cams what a wonderful subject,

I run a 312 and soon 320 , 270 is now a fast road cam . The 312 in the injection car idles at 800 no problem.


Member Services:
Holmes Racing www.holmesracing.co
MGC Racing , Alloy parts and uprated items for the C, Engine rebuilds to full race or EFI. Secondhand parts available. Facebook page "Holmes racing" www.holmesracing.co
Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#14
tjh Trevor Howcroft
Edenvale, Gauteng, South Africa   ZAF
Sign in to contact
1969 MG MGC GT
Thankyou for the many posts it would seem the UK variant for overdrive manual does not have an angle drive at either end and even if it did on a 1 to 1 gearing would not answer my problem on speedo reading. so I will service the cable and possibly get the gauge done as well.

As far as cam shaft goes so appreciate the posts and insights but I must confess I am somewhat confused. In readings that I have been doing it would seem a standard CAM has a lift of .254 inches and duration of 252 degrees and that a good street duration without impacting lift is about 270 and race spec 285 to 320. I guess I need to do more research into the matter and would appreciate any other insights. My sources Are Derek Welch motorsport, Roger Williams how to improve MGB, MGC, MGV8. Keep the views coming either way I reckon I do not want to enhance it more than 5-7% from where it is now.
Chormy's post seems in line with my understanding.

Regards
Trevor

Reply
Was this post helpful or interesting?
Yes No Thank
Re: Partial rebuild underway
#15
tjh Trevor Howcroft
Edenvale, Gauteng, South Africa   ZAF
Sign in to contact
1969 MG MGC GT
Robert
Thanks for the insight on the distributors have you any views on the Dutch 123 distributors.
Trevor

Reply
Was this post helpful or interesting?
Yes No Thank
Page 12
Topic List Forum List Newer Older Start New Topic

To reply or ask your own question:

or

Registration is FREE and takes less than a minute

Forums  

Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster





Join The Club
Sign in to ask questions, share photos, and access all website features
Forum List
MGB & GT MG Midget Buy, Sell & Trade Vendor Market MG Performance MG Engine Swaps Factory Correct MGA MGC MG Magnette 1100 & 1300 T-Series & Prewar EV Conversion Modern MG MG Motorsports Events & Meetup MG 2024 Katy Texas Other Vehicles Off Topic Clubs Archived
Your Cars
1947 MG TC
Brendan Wilson   NZL
1947 TC
Text Size
Larger Smaller
Reset Save