MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - I need a recommendation, for a Spec. mechenist

I have nothing but faith and trust in my local mechine shop to do the most of the machine work, but Im thinking a specalist might be a good Idea to have the crankshaft wedged and lightened as well as the connection rods lightened....someone that has alot of experiance with A-series 1275 engines

can anyone recommend a good shop/person, and what would be a ball park price to have that type of work done...granted, MY local shop would still do everything else.

Agian thanks guys

prop
Prop

Prop,

Contact John Mangles - www.themgdoc.com

He'll probably have a good recommendation for you.
TheMiz

thanks miz, thats a good idea...ill do, Im guessing he wont be around till next week at the earliest

What about Les out in arizonia....do you do machine work. like this.

prop
Prop

Prop. I have neither the machines, nor the experience, to do this type of work. Find out who the mechanics in your area use to have their machining done and follow their guidance.

Les
Les Bengtson

Thanks Les,

I wasnt certian if you did that kind of work or not, If anyone knows of a shop state side that has done alot of advanced work on A-series 1275 crankshafts, thats what Im looking for. thanks

prop

Prop

Prop,
How far do you want to send it?
If South Carolina isnt too far, you could try Hap Waldrop at the Acmespeedshop. www.acmespeedshop.com
I have seen his work and it is sweet and he is highly recommended.
Allan
Allan Jacks

Yup, Hap's amazing too. And he's very nice. :-)

TheMiz

Im wanting to stay in the lower 48, ideally in the middle of the country (st. louis area)(the middle of the nation is not absolute...just desirable) But definatly in the lower 48 states

I just dont know of anyone that is A-series 1275 specific. granted I know some good mechine shops that do good work, but I think I want someone that is A-series 1275 specialized for wedging crankshafts and shaving metal off conneting rods

Thanks for the Acme speed shop link, Ill look into them

prop
Prop

Prop, Hap at Acme is a great choice. However, you should be able to find a good machinist in your area without any problems to handle the rods.

Skip the crank wedging, it is money wasted on a street car.

Trevor Jessie

Prop,

You might want to consider:
http://www.aptfast.com/

I'm not sure if David Vizard is still there or not, but Advance Performance Technology is the shop he was with. Anton may have taken over the shop in the last few years.

I think the web site indicates the prices for various machining services.

Charley
C R Huff

Prop,
Hap is definitely a specialist on the A Series. He builds SCCA, races them and has a tuned MG BGT.
Take a look at one of his projects that he did.

http://www.drooartz.com/index.php?page=44
Allan Jacks

Well, I looked at haps website, Im definatly going to give him a call on monday

thanks everyone
prop
Prop

Keep in mind Hap is an engine builder. He has a machinist that he trusts to do the cranks, bores, align hone, etc. However, there is more to building an engine than machining the parts and bolting it together. Hap is very familiar with the A-series.
Trevor Jessie

>>>>>>>there is more to building an engine than machining the parts and bolting it together<<<<<<

Hey Trevor,

Okay I'll bite....what else, Jesus??? Being most of the men in my family are "Brothers of the Cloth", I think I got that one covered...lol

what else is there???

Im curious as to your thinking as to why not wedge and balance the crankshaft for a hot street engine???

Thank you for the puzzle, "My lack of intelleagnce on the matter amuses me". (Lara Croft, Tomb Raider)

prop
Prop

What else is there?
Technique and proper tools.
You will need to clean and recheck the machinist's work. Do you know the proper clearance for your pistons and where it should be measured? Do you have the tools to do it? Do you know how tight the crank should feel after you get it torqued? Are familiar with what a proper radius should look like on your crank? (I think this was a suspected problem on your broken engine). There are many clearances to check on engines as they are assembled.

I'm building an engine right now for my car. I've built other engines, but not an A-series. As I put it together I keep finding things that I question if they are correct. I research them and get the best answer I can. Hap could answer all these questions for me, but since I have not hired him to do any work for me I certainly can not ask for free consulting.

Lightening a crank will help your engine rev up faster, but it is not something you need on the street. It also changes your engine braking properties, and if you already have a lumpy idle due to cam choice then a lightened crank/flywheel will only make it more noticeable.

Trevor Jessie

Ah, good points on all, I do have all the tools to do the job, As to clearances, I figure I'll torque to the specified settings, and see what happens, obviously if something is binding or feels odd, I will certianly investagate, as to experiance, I have never done an A-series all at one time, but I have rebuilt all the differannt sect. at some time or another, the exception being the actual removal and installation of the crankshaft, rod, and pistons, and I dont see anything in that area that gives me room for concern, it appears to be like removing a rod/piston assembly to replace the rod bearings on the mazda pick-up engine I did years ago.

beyound that use basic common scence and take your time, measure twice cut once approach, use the right tool for the current task, I dont see the rebuild being a problem

As to lumpy ideal, Im planning on going .60 over so that will take alot of the lumpy out, which I dont think the SW507 swiftune has alot of anyway

On the crankshaft, the reason I want to sub it out to someone like "Hap" is I really want someone that has done a few of these crankshafts to do the filet radiuos, lighten the chrankshaft...meaning knowing where to take the metal off of, and might as well let them balance while they got it, If this crankshaft was just a common 16n crankshaft, but because this is a rare crankshaft 1 of 1000 made, Id rather go the extra mile and do it correct the first time.

the one real drawl back Im really conserned with by using an aluminum flywheel, and lighted drive train is the amount of momentum on long hills

prop
Prop

You did say one thing that has me concerned,

you said he farms out all of his machine work, does that mean he wont take on my machine work of just the crank and rods?, in other words he will want to do the whole engine and not just the few pieces, which I can understand that.

prop
Prop

I guess he would do the rods and crank. But if it were me I would have him port the head and let a local machine shop with a good rep lighten and balance the rods and turn the crank. Or... you could have sean brown port the head.
Trevor Jessie

Treavor, my fear is this,

I have a great mechine shop been in business about 60 years, and does alot of race car work, but its all Ford, chevy, and dodge an lots of common inport, toys, honda, bmw, ect.

So I have no problem with them doing the basic stuff re-boring, straightening the crank, turning and polishing the crank, ect.

its the so called fine detail stuff like the filet radius, knowing where to remove the metal esp. on the connection rods, "Hap" says he can remove 100 grams, Im not sure My mechine shop would know where to remove 100 grams off each rod for an MG midget, for a 454 chevey I have no doulbt they could do it in there sleep


THR MEAT AND MAIN PART OF MY CONCERN
Are my fears real, or is mechine work, just mechine work, does it matter if the connection rods came from a chevy or a 1275, you seen one lightened rod and applied a filet radius on one chrankshaft, its the same for all, no matter the make, brand, or model...my gut tells me its not the same, am I wrong, is one engine is just like any other??

If I am correct, then that is why Im looking for a more A-series 1275 experianced specific mechine shop to do just the pieces I doublt my well trusted shop has ever worked on before.

prop
Prop

Prop, don't spend 90% of your money to get the last 10% of performance. For a street car spend your money to get balanced to get 90% of the performance and use all the extra cash (that you didn't spend on the last 10% of performance) to make the car handle well on the street.

Just my opinion. Call Hap and see what he can do for you. He won't steer you wrong on where to spend your money.
Trevor Jessie

Prop. Yes, being familiar with the engine you are working on and having done several before is a very good thing. If you want specialty tasks performed, such as lightening the connecting rods, you want someone who has lightened those connecting rods before. Such a person will have a better understanding of what works and what will not work and has the best chance of doing the custom modification in a manner that will be reliable for the long term.

I agree with T-J that the last little bit of performance is wildly expensive and few of us would appreciate it. Perhaps Bob (Robert) might address this. He was a champion Midget racer and should be well qualified to address how expensive it is to get that last one half horsepower out of an engine. Needed, on the race track, but not really needed on the street.

You are worrying, excessively, on the "filet radius" when this is a "standard shop practice" type of thing. It should not change from engine to engine because, in this, they all have the same needs. Any machine shop should be able to grind the bearing journals in a competent manner.

But, it would be much better for us to focus on what degree of undersize would be desirable/allowable when doing a performance rebuild. My own engines use crankshafts which have been turned no more than .010" undersized on both the main and rod journals. Again, this is an area which Bob (Robert) could make a significant contribution to.

Les
Les Bengtson

Thanks everyone,

I do tend to get lost in the details in projects like this, And Im certian thats where I am at currently, I'll go back thur my notes and sources and figure out what is needed and re-evaluate, perhaps your correct my local mechine shop can handle everything.

one aspect Im dealing with is called "In for a penny, in for a pound" a vary common problem I deal with on alot of projects like this.

Currently with the en40 crankshaft and the Aeg-521 connecting rods and the basic mechine work,(aka line boring, magniflux, polishing, ect. ect.) EXcluding the exotic stuff like wedging, taking 100 grams off each rod ...Im looking at over $1000 for parts and labor, at this point whats an extra 200-300 dollars to go all the way....Im just not the type of person that spends $500,000 for a rembrant painting then use a wal-mart picture frame.

To me qaulity cost money, I certianly dont need this type of quality in my work truck, but for a car Im planning to use as a coffin at the end of my day...hopefully 50 years from now...I think quality should be the 1st thing on my agenda.


Back to the flogging table of reality
prop
Prop

an added note

If I were using a common 16n crankshaft, and common everyday Aeg 625 connection rods, Id certianly not want to go the extra distance as Im currently driving head long into, after all these parts are common and cheap and easily replaceable

So am I assigning to much value to my en40 crankshaft 1 of only 1000 made, and my Aeg- 521 rods, that are apperantly well sought out for as well, Trust me those 5 items where not cheap, I certianly dont mind adding a few extra dollars to get the most out of and the Insureance to a life time of protection.

After all it dosnt make much scence to spend $125 a sq. yard for carpet, then go cheap and buy a $3.00 a can of do it yourself carpet sealent/protectent.

prop
Prop

This begs the question Prop. Why do you feel like you need the EN40 crank and AEG-521 rods?

I honestly do not know the value or worth of those components. But, I know there are plenty of fast spridgets on the road without those components.
Trevor Jessie

Aaahhhh ....cool factor?, LOL.

It just sorta happened, But not totally by acceident, when the engine blew up at the crankshaft at normal driving speed, it certianly had an effect and strongly effected both my Phyci as well as my design thinking, so my engine devoloped 2 primary goals, high performance, and bullet proof.

When I learned I needed a new crankshaft, devine providence stepped in and the the EN40 came up on ebay, after some discussion and debate on here and talking to others, it just seemed like a great Idea, then when the Aeg 521 rods came up, and some further discussion, It was Mark T. That made an un-aviodable point that I simple couldnt argue with, and sealed the deal for me. "The 521 rods would give credablity to a well thought out high performance engine"

It was after getting these parts that it occured to me, the mods I want to make are sorta "one shot" mods, If the mechine shop screws it up...not only did I just lose a chunk of money, but the parts are essentially non-replaceable, so the need for high experiance is curical, where as the N16t crankshaft are common and can be had for $75 any day on ebay, so it wouldnt bother me to have my trusted mechine shop screw those up all day by trying to wedging it

I just feel that these parts need to be done right the first time....as there are no second attempts

prop
Prop

Prop,
I understand what you mean. I have been doing some reading on engines and replacement and going back and forth about what I need to do and even if I have the skills to do it. My buddy at work who is has a Mustang said thats the only way you will ever learn if you ever do it yourself. I still have some convincing and have not made up my decision, but you dillema brought up a good point from my reading. In one of the posting stated when you use a professional for the job, they have already made the mistakes and that are less willing to take risks because that is their job and that is what you are paying for. I know the cost of the White Healey was about 5K but that was the full engine parts and labor. Where are you willing to put your risk, in somebody that may be unfamiliar with these expensive parts, or somebody that has probably worked with them in the past.
Just my 2c
Allan (Who still doesn't know what he is going to do) Jacks
Allan Jacks

Prop,

I understand your consideration for the high dollar and rare parts that you have accumulated for your build.

Do you have David Vizard's book on the A-series engine?

I assume you do, so I don't understand why you have not considered my earlier suggestion to investigate Advanced Performance Technology for the machining.

I believe I am correct that many of the machining pictures in the book came from that shop.

Charley
C R Huff

Hey CR,

Like my grandmother used to say, If you cant speak well of someone else, dont say anything at all. (unless its about george bush...thats fair game...lol)

Thats all I have to say, and will say as to APT

prop
Pro P

This thread was discussed between 24/12/2008 and 27/12/2008

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.