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BJ7 Engine Rebuild and Mods

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sfovc2003

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This is a great forum and a great source of helpfull info for me. I just started a nuts and bolts resto on my BJ7 (hopefully to concours standard, but I'm still somewhat undecided) and am getting ready to send the engine out for a complete rebuild. I have heard and read much on what should be done from a variety of sources, but would like to hear some opinions from this group as well. At present, I plan to have the engine blueprinted and balanced, the head ported and polished (and milled if needed), the cam ground to BJ8 specs, and the flywheel lighted by about three pounds. Should I consider an aluminum head (I have some room in the budget)? Should I upgrade the carbs to the 2' SUs from the current 1 3/4s? What about a heavier duty clutch? I want to maintain drivability, but extract as much power as I can. How much horsepower and torque is it reasonable to expect with this engine with these kind of mods?? I would love to hear this group's suggestions and advice. Thanks.
 
Those Modifications fall side out of the concourse envelope. ---Keoke /ubbthreads/images/graemlins/nonod.gif
 
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At present, I plan to have the engine blueprinted and balanced, the head ported and polished (and milled if needed), the cam ground to BJ8 specs, and the flywheel lighted by about three pounds. Should I consider an aluminum head (I have some room in the budget)? Should I upgrade the carbs to the 2' SUs from the current 1 3/4s? What about a heavier duty clutch? I want to maintain drivability, but extract as much power as I can. How much horsepower and torque is it reasonable to expect with this engine with these kind of mods?? I would love to hear this group's suggestions and advice. Thanks.

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As Keoke said, those Modifications fall side outside of the concourse envelope. If this is not really important, your mods should give the same performance as the late BJ8, plus a little. all good ideas.

The flywheel lighten will make it more responsive to the throttle, especially in the lower gears. The BJ8 clutch will help. The late BJ8 cam profile will help. The HD8 carbs will help.

Be very carefull about changing the ports. It should be done by someone who has real world practical experience in porting this particular engine. Port gas velocity & entry angles to & through the valves is much more important than port size & maximum flow capacity. Often what would appear to work better actually hurts port performance.

A good aluminum head, such as the DW full race complete # CENG 999AF, with all of its accompanying valves, springs, guides, studs, washers, etc. Will give the very best performance with your other parts & already be optimumally ported. The cost is high though, probably around $4,500 USD. It will also reduce front end weight for better handling.

Don't forget to use good tube headers such as the DW CEXS120, plus muffler & tail pipes To top things off. Likely another $800 USD. The head & headers could add another 20% power to the late BJ8 specs.

It is assumed that you will use only top quality parts & machining in the rebuild to reliably extract this additional power.

It all depends on how much you wish to pay. You could end up with $10,000 in a very good performing engine, or less for something inbetween.
D
 
It depends on what you expect out of the little cars. I am 54 and have raced almost everything with an engine that floats,drives or flies and have found that there is a lot to be said for just plain old enjoyment. If you want all that performance Ford is making the GT-40`s again but as for me give me something that I can depend on that performs like it was designed. Build a good ,clean ,stock engine that is balanced and spend your money on sway bars, new bushings, good tires and I am sure you will enjoy the car much more. The mods you want will all affect reliability and driveability and if you figure out the cost of HP/$ ratio it will scare you. Just my 2 cents worth. Skip
 
Good advice and certainly food for thought. Based on your collective input, I think I'll scale back my plans somewhat and stick to the mods that will improve performance but remain out of sight from the concours judges. Someone else warned me about the potential loss of performance from porting. Also, the cost of the aluminum head made me gulp. What about forged pistons and an increase in compression? Finally, I assume electronic ignition is a must. Drivability and reliability is a priority (I drive my cars).
 
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Finally, I assume electronic ignition is a must. Drivability and reliability is a priority (I drive my cars).

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I must admit I have my own opinion on electronic ignition - so much I wrote a short article for our car club - if you want another opinion - check out - Electronic Ignition? /ubbthreads/images/graemlins/cool.gif
 
For my two cents worth, Healeys have all the performance they need for what they are, which is a car designed and built 40's and 50's technology. Unless you are into sanctioned vintage racing, Healeys are suited to leisurly driving, and modifications are best kept to those which improve safety and reliability. If you want a high performance street machine put your money in a Bemmer, Porche, or such.
 
Bob's article on electronic ignition was interesting. It seems like half the mods I was considering may not be such good ideas after all. But that's why I posted my original question. Interestingly, my 72 E-Type is fully restored ... and bone stock. Any other tips, tricks or warnings are appreciated.
 
[ QUOTE ]
[ QUOTE ]
Finally, I assume electronic ignition is a must. Drivability and reliability is a priority (I drive my cars).

[/ QUOTE ]

I must admit I have my own opinion on electronic ignition - so much I wrote a short article for our car club - if you want another opinion - check out - Electronic Ignition? /ubbthreads/images/graemlins/cool.gif

[/ QUOTE ]

Bob--

I laughed out loud when I read your article. Luckily I formed your ultimate conclusion: "If you feel you MUST fit electronic ignition, my advise would be to buy a new distributor that already has the components fitted" at the beginning of my quest for the perfect fix and bought a Mallory Unilite distributor. Yes, it was expensive but it is very big and very red and has that expensive "Mallory" name written all over it. But with the exception of a ground wire's once becoming disconnected it has been trouble-free.
 
I am restoring my BJ7 to Concours specs and the engine is in the shop right now. Most of what you mentioned can be done within concours guidelines ... BJ8 cam, clutch, balancing, porting, etc. Obviously, the 2 inch carbs and alum. head would get you deductions but all the internal modifications will never be seen by the judges.

I'm going with the BJ8 cam and lightened flywheel. I had the head and intake/exhaust ports matched (brought out to the dimension of the manifold gasket) but no polishing or extra porting. My engine guy said it was better not to polish with this manifold setup ... something about the roughness helping the gas/air swirl properly. I also have roller rocker arms which I found to really help the motor rev smoother and quicker. I did have tube type headers on the motor but have switched back to the stock system for now.

I'm keeping the ignition stock. Peter and Ann Hunt went around the world in 2000 in a BJ7 with the stock setup and didn't change or adjust the points once. I think if you rebuild the distributor you reduce the extreme wear that you get with an old distributor. Other "mod's" that can't be seen are the 3.54 gears in the rear end and the rear oil seal kit for the motor.

Cheers,
John
 
[ QUOTE ]
[ QUOTE ]

I must admit I have my own opinion on electronic ignition - so much I wrote a short article for our car club - if you want another opinion - check out - Electronic Ignition? /ubbthreads/images/graemlins/cool.gif

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Bob,
I do hope that this is intended to be comedy. Anyone with this little amount of knowledge about things mechanical & electrical should never touch a car. Alas, it is all too common an occurrance & a big reason why electronic ignitions have a bad name. Still hope you weren't serious. /ubbthreads/images/graemlins/tongue.gif
D
 
The picture on the web page is from an actual install done by one of our members - I wont mention who, as I put a link from our club site to here, however I have since removed 3 electronic ignition kits from Brit cars since I have been involved with the club. My experiance has been that kits do not return any value for the money (my opinion). I carry a spare set of points and a condenser in the trunk, but to date have never had to use them. However - I have heard tails of woe that people have had to be towed/trailered home because they have no spark! I will make no comment on the mechanical ability of many/some British car owners, but in their defense it usually says "Easy 5 minute Conversion" on the package - but they avoid self assembly units from Wal Mart like the plague! Ever noticed that most of the cars that have been converted are RED? /ubbthreads/images/graemlins/wink.gif
 
I forgot to tell you I am rebuilding my engine right now. I am going with a bone stock engine with the exceptiions of thermal barrier coating the piston domes and a 4 pass radiator core both to help keep the engine cool, dry film lubricant on the piston skirts and crank journals to help with startup lubrication, a rear seal mod and a spin on oil filter and thats it. When you get into porting and polishing you ABSOLUTELY need a good flow bench because you get into things like charge velocity and fuel air charge stratification . Ports to smooth and the fuel settles out of the charge and fuel/air charge seperates. Small intake ports tend to produce more torque and less rpm due to increased fuel/air charge velocity. Big smooth ports tend to produce high rpm at the expense of low rpm acceleration. So for a good street engine my ideas are " If it ain`t broke don`t fix it". You could very well take a grinder to your engine and end up with a DOG if you aren`t careful. New rings, bearings, gaskets put it togther clean keep it that way and just go have fun. Skip
 
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Ever noticed that most of the cars that have been converted are RED? /ubbthreads/images/graemlins/wink.gif

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Yeah - I wonder why. Any ideas?
D
 
John:
Your reply was quite helpful. I would love to talk to you sometime and pick your brain a bit (talking is so much easier that typing, at least for me). I'm up here in San Francisco. Can I track the progress of your car? I am presently disconnecting everything under the hood so the engine and trans can be pulled (not by me) and the rebuilding process begun. I'll then proceed with the disassembly of the car myself. Most of what I will be doing is disassembly since this is my first nut and bolt resto and my competence is somewhat limited. Steve Gordon at Vintage Auto in Oakland did the resto on my E-Type and, although he has some (but limited) experience with Healeys, wants to work with me on the BJ7. I know he's a good mechanic and trust him explicitly, so that's how we intend to proceed.
 
Quote:
"I do hope that this is intended to be comedy. Anyone with this little amount of knowledge about things mechanical & electrical should never touch a car."


Are you talking about him or me?
 
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John:
Can I track the progress of your car?

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Sure, I just sent you a private message with my contact info. Make sure you get a copy of the concours guidelines (even if you aren't going to have the car judged). There is valuable info on color, finish, details, etc which will help. https://www.healey.org/concours-registry.shtml

Cheers,
John
 
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Ever noticed that most of the cars that have been converted are RED? /ubbthreads/images/graemlins/wink.gif

[/ QUOTE ]

My car was red before I converted to the Mallory Unilite--all ducks are birds but not all birds are ducks!
 
I rebuilt the engine in my BJ8 with a no lead head, reground cam, rebuilt HD8 carbs and bored .030 over. This setup gives me all the performance that I
need. I am using the original distributer. I have about $4000.00 in the engine. I could have gotten some more horsepower out of it, but the cost of it would have been prohibitive. My advice is to build a dependable engine
that gives good performance at a reasonable cost.
 
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