• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Getting more horse power from a Healey 100

Share this page

My totally stock BN1 is fast enough for me. I particularly like that torquey engine and that tall synchro first gear on the BN1, it keeps up with traffic easily. The brakes and handling, however, are really not near anything contemporary. I am reluctant to really push this car seriously on a mountain road. I have driven a well sorted 100M and it definitely has hotter performance at the high rev side, though it's pretty much the same at low RPM. I think if I wanted to improve my BN1, I would look into a disk brake retrofit, it could use that a lot more than more horsepower.
 
drambuie said:
.

I definitely would love to drive a well set up 100M for comparison to my 67 Stock BJ8 for instance. I too have been planning a "Special" build Healey 100 or a BN6 two seater. I always like to match high preformance suspension, steering and braking upgrades to engine upgrades proportionally. As I was saying in my first post, I want much better preformance In the 0 to 80 range with improved torque..I am not really concerned with top end as most of my driving is on open country roads with twists and turns and 100 mile drive morning coffee trips on the weekends down Route 66. This is what I have in mind...
Click to expand...

Our 100M is quicker off the line, but I attribute that to the 4.1:1 rear end in the M as opposed to the 3.54:1 rear end in the BJ8 (plus the M has a fresh rebuild and the BJ8 engine is getting a little tired, and the 3000 has a lot of stuff--parts, tools, etc.--in the boot). The 100, not surprisingly, is more nimble but the 3000 is a better cruiser.

Further on our conversation of 'Healeys vs. Civics' is the concept of 'energy management.' Any pilot knows what I'm talking about, but most drivers are clueless: note the way many drivers will be cruising at 80 on the flats, but as soon as they start pulling up a grade their speed will gradually fall off--apparently, they haven't heard of 'gravity'--and when they reach the crest of the hill they will start to accelerate going downhill then slam on the brakes when--surprise!--they are going faster than they realized. I see this every day on my commute over the Sunol Grade near Fremont, and it annoys the heck out of me. Also note the way some people 'jackrabbit' from one red light to the next, when if they'd just pick an average speed they'd hit a few of the lights. I once had a Canook tell me my brake lights were out after I had carefully engine-braked and coasted into a stoplight without using my brakes at all. Oh, and the housewife passing people on Hwy. 2 whilst talking on her cell phone has little to no margin for error left, whereas any Healey driver knows to give him/herself plenty of 'wiggle room.' Like I often say, anyone driving faster than me is an idiot.
 
Unless your 3000 is grossly out of tune I do not suggest you get a 100 if you are not satisfied with the speed of your BJ8. Though lighter and better handling the fours have a lot less HP and unless you do some serious and expensive modification I don't think you would be able to make one as fast as your present Healey. To develop substantially higher power you will have to do a lot of porting and run a highly radical cam which will cut into the car's streetability and it will be rather lumpy except when at speed.

I have a DW Stage 2 cam on my 100 and even with the AL head, tubuliar exhausts and larger M-spec carbs the 100 is simply not that fast a car, and I drive my Healey rather hard, usually revving to 4500 in first and second. To be sure it feels fast due to all the noise and wind but if you want real speed get something else, maybe one of those new Prius's they were advertising on the Superbowl.

My tow vehicle, a 2007 Toyota Tundra, does 1/4 miles in about half the time of my Healey and most certainly is faster than any of my race cars.
 
Last edited:
Here's an unsolicited suggestion. If you want modern performance in an LBC, I'd be looking at the MGB. They are cheap to buy and relatively easy to swap in a variety of V6 and V8 motors. There are even kits available for the swaps. The rubber bumper cars were built with the idea of fitting the factory V8, so they don't require much modification at all. The buy-in for even a crummy 100 is high and then you have to worry about the structural stability of the frame or even buying a Jule. With the B, you could even look at a GT and add AC for even more comfort. Plenty of ideas here: https://www.britishv8.org/Photos-MG-Conversions.htm and here: https://www.mgexp.com/phorum/list.php?40
 
I have owned,rebuilt and enjoyed various British Sport cars for over 28 years and defiantly know the "essence" of owning and driving them. Actually, I enjoy restoring them as much as driving them and for the most part I tend to be a purist. I always considered myself as a Care taker first and a owner second, As to faithfully pass On My Healey's or what ever Vintage Car I own to the next generation in its true intended form. I never thought of adding various internal motor upgrades as a bad thing! As I was saying in my early post, if I can extract 150 HP. from a Healey 100 that would work for me. I would think with the right combined Denis Welsh motor upgrades I can achieve 150HP and add a nice performing Healey 100 to my stable. However, I do have a "special" build in mind and the gloves are coming off for this one! I already have it on paper, now need to just build it as soon as I get things in order.

Michael Oritt, My 1967 BJ8 is in perfect tune..Runs just fantastic! To be honest, if thought I could not get a BN1 or BN2 to run with my stock 67 BJ8... Your right, I should not own one.

Healey Rick, You are so right! their are other less expensive British marks to have fun with, and the best I think is a TR6 with a S2 spec motor ungrade along with the endless list of other preformance components available for both motor and suspension. I already have done this and can tell you... My built Tr6 would run circles around any of my Healey's especially when it comes to handling....a lot of fun those Triumphs :smile: By the way, I was checking out your "Exploder" project, your V8 looks like it belongs there! Thanks for sharing the project documentation and all the personal comments... Always fun and interesting to read your posted comments as well! A fun mixture of bantering wit and tech makes for a great forum!
 
drambuie said:
Healey Rick, You are so right! their are other less expensive British marks to have fun with, and the best I think is a TR6 with a S2 spec motor ungrade along with the endless list of other preformance components available for both motor and suspension. I already have done this and can tell you... My built Tr6 would run circles around any of my Healey's especially when it comes to handling....a lot of fun those Triumphs :smile: By the way, I was checking out your "Exploder" project, your V8 looks like it belongs there! Thanks for sharing the project documentation and all the personal comments... Always fun and interesting to read your posted comments as well! A fun mixture of bantering wit and tech makes for a great forum!
Click to expand...

Thanks for the kind words. One of the great things about this forum is that there's never any name calling from those whose taste runs to original cars. Modifying a Healey, whether it's an engine swap or improving the performance of the stock items can be a real challenge and figuring out how to make everything work together is a large part of the fun and sometimes the frustration. We probably all have a "dream Healey" somewhere in our minds and I know a number of folks who've chased that dream after building their first Healey to stock. As far as my comments go, under my senior picture in my high school yearbook my classmates put the phrase "A little nonsense now and then is relished by the wisest men." Some things never change.
 
I would love to drop a BMW diesel into a 100 (similar rev range) and build a car that outperforms the orignal and gets an mpg I can live with! However with the value of Healeys these days it would be difficult to justify unless I had a spare bodyshell hanging around (which I don't)!
 
Drambuie--

While I think we can all agree that Healeys can no longer be considered "fast" cars, when they were produced they certainly offered equal or better performance than other medium-displacement cars and a well-driven Healey could out-accelerate, and handle as well as, most contemporaries.

As a solution to your feeling that your 3000's performance is just "acceptable" I suggest that you view and drive it as a "momentum" car, one that does not have the ability by virtue of big HP/high torque to quickly recover speed lost in corners, braking, etc. and so is driven in a manner to maintain, as much as possible, its "momentum". Just google "momentum racing" and I think you'll get a number of hits that might be helpful.

Though this is a racing technique it has its place on the road--especially the open road--and when, for example, you see an overtaking situation try to time your pass so that you never get off the throttle. And if you must slow down to wait for an opportunity to get around the car in front of you leave enough distance so that you can start to accelerate well before you change lanes so that your car will be on its power curve at the right moment.

Keep your eyes open, your revs up and your foot off the brake--it will make things more exciting!
 
I don't know whether it was the forum but an NZ owner put his 100/6 engine on a dyno and it made 84 bhp, I put my BJ7 on a carefully calibrated rolling road and it gave 101bhp and 148lbs/ft at 3000 rpm. Now I've meticulously built a standard BJ8 engine and had the head gas flowed to 1965 Works spec with an ex BMC competition department employee overseeing the job. I'll report back once we've set it up.

My BJ7 is in good condition with new shocks, springs, steering box etc, it's pleasant enough to drive at a moderate to brisk pace and it's not difficult to control if it slides, usually tail first. At higher speeds it's light on the front and has vague imprecise steering. Forty years ago, I didn't notice. Now I do. The BJ8 engine will give it a 0-100 time a couple of seconds slower than an 2 Litre MX5/Miatta, so comparatively fast for a fifties chassis. My recalibrated to original spec speedo shows 100 when the car is doing 84mph! The speedo is the mostly highly tuned part of the car!

I don't intend tend to try and get more power from the engine because I don't want to lose low end torque and have to rev the thing harder to get along, because that's what happens if you fit a faster cam. There are two ways to increase power; more revs from a faster cam or more torque and power from forced induction. Carbs and exhausts make a relatively small difference.
IMO a Healey is what it is, a wonderful old character car, one of the most beautiful ever made and with an incredible history. Best accept it for what it is and buy a Boxster a better, faster experience IMO.
 
Michael Oritt:

Absolutely, momentum driving/racing is what I naturally always have done. As matter of fact I make most use of the avaliable torque and controlled speed in each gear when going into a corner and sling shot out of the corner at a greater speed onto the straight as I combine my momentum, Gear select, speed and getting the motor high on the cam all at the same time. I have always called this the "slingshot" and used best when exiting the inside of the lane and shooting out to the straight and then shifting to top gear for top speed. i used this technique when I raced Flat track and TT motorcycles, Enduro racing as well.

I use this same technique when driving my Healey to gain a advantage over less skilled drivers with more horse power then me. On the straights it's more of a timing thing and sometimes I draft another passing car in front of me as we both pass another vehicle together. So yes, their are ways we can tactically drive our Healey's and have great fun doing it! Very glad you raised this point!
 
Ev2239: I am glad you have shared some of your dyno findings..I am particularly interested in the dyno readings of your BJ8 when you get it tested.. As I am sure many on this forum would be curious to see. Please keep us posted ok! In my early post I was trying to reach out to Healey 100 owners and big Healey owners for that matter to share their dyno findings with us. Especially the folks who have upgraded with flowed heads, exhaust, a little higher compression and some of the other basic mods. So many people have spent a awful lot of money on on particular motor preformance upgrades on their Healey's but how many actually preform a before and after dyno test to see if the money was well spent? Does Denis Walsh have dyno testing results for there much touted preformance motor items? Haven't seen them yet!
 
drambuie said:
Ev2239: I am glad you have shared some of your dyno findings..I am particularly interested in the dyno readings of your BJ8 when you get it tested.. As I am sure many on this forum would be curious to see. Please keep us posted ok! In my early post I was trying to reach out to Healey 100 owners and big Healey owners for that matter to share their dyno findings with us. Especially the folks who have upgraded with flowed heads, exhaust, a little higher compression and some of the other basic mods. So many people have spent a awful lot of money on on particular motor preformance upgrades on their Healey's but how many actually preform a before and after dyno test to see if the money was well spent? Does Denis Walsh have dyno testing results for there much touted preformance motor items? Haven't seen them yet!
Click to expand...


This may help. When the "Honda Accord 100M Lemans" was listed on BaT the seller was saying it had an estimated power output of 200 hp, which was not supported by any dyno figures. He did say he was going to run it on the dyno and in the current ad it's listed as 115 hp, which would be RWP. Pretty healthy motor and IIRC all the parts were supplied by Denis Welch. Here's what the ad says was done:

[h=2]Over $50,000 was spent on the following, the engine rebuild and upgrade resulting in a performance upgrade and horsepower increase to 115 dyno tuned horsepower.[/h][h=2]Work performed is as follows with all records and receipts available:
The engine rebuild to M Fast Road specifications included a Steel Crank and Rods, 88.5mm Forged Pistons, Aluminum Cylinder Head, Competition Steel Head Gasket, Steel Flywheel, Aluminum Sump, new Oil Pump, Sport Camshafts, Steel Rockers, Vernier Cam Sprockets, New Timing chain, Narrow Fan Belt Conversion, New Water Pump, Aluminum Radiator, Oil Cooler Kit with spin on filter conversion, Alloy Heat Shields, New Exhaust Manifolds-Headers and New Stainless Steel Exhaust System.[/h]
 
For comparison an XKE has a claimed HP of 265 yet on a calibrated rolling road 170 is average. A friend has a very fast one that revs past 5000. It's an early UK 4.2 and has a pronounced increase in power from 3000 so almost certainly "fast road" Camshafts fitted. It produces 190bhp.

The claimed power for most modern engines are far more accurate.

I must say say it's easy to see why people fit American V8s. They're cheap and much more powerful, but presumably heavier still and may not help handling.
 
i have a couple of those "souless healeys". took the soul out of a 59 bn6 in 1968 and never looked back. i love the healey looks...preferably the two seaters but i want more than 100-150 horsepower! as a matter of fact just recently sold a stock bn6 two seater before i put in a v8. then i found a v8 bn6 to build to my taste..no doubt most stock healeys are just to expensive to convert. factory horsepower is fine for cruising but i suffer from the hotrodder mentality and have never been much of a purist and of course my bank account suffers greatly. i do appreciate the forum being as graciousas they are to us modifiers! as a note...a couple years back, i converted my 78 930 to ls7 horsepower....705 chp in a 2300 pound car! i did take a beating from the purist on the porsche forum for that! and, about the same time 930 values skyrocketed so my wallet took a real beating! i sold the car a year ago but i still have my 71 911 with a dart all aluminum 434 cubic inch sbc with efi that makes almost 600 chp......so ill admit it....i am afflicted!!!!
 
Max wedge,

i can certainly understand your quest for more horsepower. In fact I have seen a few Healey 100 V8 convertions I really lusted for. One in particular was offered on eBay 2 or 3 years ago. It was black with a red interior converted to a very high professional standard including the suspension and brakes. I am still kicking myself for not buying it at the time and if it ever comes up on the market again and i have a few extra dollars to spend I plan on making a offer for it. As for now, my mind is full of projects.
 
HealeyRick said:
This may help. When the "Honda Accord 100M Lemans" was listed on BaT the seller was saying it had an estimated power output of 200 hp, which was not supported by any dyno figures. He did say he was going to run it on the dyno and in the current ad it's listed as 115 hp, which would be RWP. Pretty healthy motor and IIRC all the parts were supplied by Denis Welch. Here's what the ad says was done:

Over $50,000 was spent on the following, the engine rebuild and upgrade resulting in a performance upgrade and horsepower increase to 115 dyno tuned horsepower.

Work performed is as follows with all records and receipts available:
The engine rebuild to M Fast Road specifications included a Steel Crank and Rods, 88.5mm Forged Pistons, Aluminum Cylinder Head, Competition Steel Head Gasket, Steel Flywheel, Aluminum Sump, new Oil Pump, Sport Camshafts, Steel Rockers, Vernier Cam Sprockets, New Timing chain, Narrow Fan Belt Conversion, New Water Pump, Aluminum Radiator, Oil Cooler Kit with spin on filter conversion, Alloy Heat Shields, New Exhaust Manifolds-Headers and New Stainless Steel Exhaust System.
Click to expand...
. Wow.. $50,000 spent on some motor upgrades? And the result is 115 Hp on the dyno. I have to wonder what his total investment is in this car? In my humble opinion if he would have restored this 100 to its original factory color, trim and motor configuration and stayed away form the "M Thing" ...he would be sitting in a much better place right now.
 
The Healey 100 engine is four cylinders taken from a six cylinder Austin Truck engine that had cast iron pistons and was designed before WW2. I say 115bhp is quite an achievement from something as old.

Healeys or or good original cars in exceptional condition are becoming extremely valuable, so there is incentive to keep them original.

Drambuie has has made a small fortune out of an extremely large one. :(
 
I have another argument for a "modified" Healey... save a Healey! I'm in California and so many Healey were hot rodded back in the day and many of those ended-up in hedges. When I was alerted to the 100 (that I would later buy) I tried talking myself out of it by arguing to myself that it wasn't original. Then I saw the car; not running, dingy and dirty but with those magnificent lines all I could say was wow. Then it became all about putting the car back on the road. Honoring the British and American history of the car. So if the example isn't too far gone, a lot of fun can still be had behind the wheel. That's what I still think when I see cars like this one... https://www.ebay.com/itm/191806332366

It will never be original but someone can make it their own. I don't know the seller but I know I want to see the car driving around the Bay some day.
 
Back
Top