Getting more horse power from a Healey 100

[drambuie]

I have been seriously thinking of buying a Healey 100 for my next weekend driver... However, I am a little apprehensive because of the lower base horse power, the last thing I want is a sports car that looks fast standing still, but won't get out of its own way because it is so under powered! A safety issue in today's fast moving traffic. My 1967 BJ8 is exceptable with decent cruising and passing power..(barely exceptable) at 150 rated (aledged) horse power. Anyway, I just wanted to ask some of you Healey 100 owners if you had added any additional upgrades besides the usual M mod to get some decent horse power to weight ratios out of the little Four banger and retain reliability. To me, at least 150 HP. would be acceptable. ( (barely) acceptable that is! Realisticly, all I am looking for is to get from 0 to 80 mph without getting run over by a Honda Civic!

I know Denis Welsh sells many performance items for Healey's including the 100, but I haven't seen any real performance data relating to all the combined engine performance items he offers! A nasty boy mod is out of the question as I want the Healey 100 to retain its soul!

Unless the Devil makes me do it!

 

[HealeyRick]

Unless the Devil makes me do it! View attachment 41405

Go for it!

 

[drambuie]

Rick...why did I know YOU would be the first one to push me over the edge! Lol. Is that your Healey? Looks like the carb has a oxygen enhancer. :lol:

 

[HealeyRick]

I WISH this was my car! The "oxygen enhancer" is a Paxton supercharger. Only thing I'd change is the automatic transmission. Here's some more background: https://www.mecum.com/lot-detail/FL0114-174295/0/1957-Austin-Healey-100-4-BN2/Automatic/ and https://bringatrailer.com/2011/06/25/bat-exclusive-1956-healey-100-gurney-weslake-v8/

My car is much more plebeian. It's a BJ7 that was a former SCCA racer. With an Isky T3 cam, triple HD8s and a ported head, I expected it to be much quicker than a standard car, but it wasn't that impressive. That's when I decided to do the V8 swap. It's a standard looking car until you lift the bonnet or start the motor! Here's a link to the build: https://forum.britishv8.org/read.php?13,8264

 

[Bob_Spidell]

I have been seriously thinking of buying a Healey 100 for my next weekend driver... However, I am a little apprehensive because of the lower base horse power, the last thing I want is a sports car that looks fast standing still, but won't get out of its own way because it is so under powered! A safety issue in today's fast moving traffic. My 1967 BJ8 is exceptable with decent cruising and passing power..(barely exceptable) at 150 rated (aledged) horse power. Anyway, I just wanted to ask some of you Healey 100 owners if you had added any additional upgrades besides the usual M mod to get some decent horse power to weight ratios out of the little Four banger and retain reliability. To me, at least 150 HP. would be acceptable. ( (barely) acceptable that is! Realisticly, all I am looking for is to get from 0 to 80 mph without getting run over by a Honda Civic!

I know Denis Welsh sells many performance items for Healey's including the 100, but I haven't seen any real performance data relating to all the combined engine performance items he offers! A nasty boy mod is out of the question as I want the Healey 100 to retain its soul!

Unless the Devil makes me do it! View attachment 41405

I don't understand the problem. I have 2 Big Healeys--a BJ8 and a BN2/100M--and I drive them everywhere (California--in particular the SF Bay Area where I live--has a bit of traffic). I also have a Mustang GT with 315HP and a 5.2-second 0-60MPH time. I don't drive the Healeys like I do the Mustang, where I have a lot of power on tap. I drive the Healeys with more planning and forethought; e.g. when attempting to merge in fast-moving freeway traffic I pick a slot in traffic that is moving at a speed that I can accelerate to in a reasonable amount of time. And, believe it or not, many if not most people understand you're driving an older, less-capable vehicle and 'cut you some slack.' They'll get impatient if you aren't doing 80 in the fast lane, but that's what the Mustang is for. It's like flying an airplane--you can get out of trouble in an F-15 by standing it on its tail and lighting the burners, but you can't do that in a Piper Cub, and you have to plan and fly accordingly.

If you want more pop in your Hundred, I've heard from reliable sources that a bore, higher-compression pistons, a Denis Welch head, larger carbs, headers and a hotter cam will give a 'stock' Hundred more HP than even a 100M. Have also heard that Jeremy Welch will give performance data if asked.

 

[turtle]

Don't think of it as selling the Healey's soul or going to the "dark-side"... think of it as a sprinkle of Yankee magic to turn the charming British roadster into a hooligan (potentially). I can report that my car will never be "smoked" by a Civic or a Cayman for that matter. Actually most gear heads are stunned a bit by the looks of the Healey so you'll get them of the line every time... always driving responsibly of course. Also, my Chevy/Ford drivetrain is very shop/parts store friendly.

I'm jesting a bit. I'd never swap out an original drivetrain (or I'd keep it in a crate). If you seek to upgrade the stout A90... There are examples of those intrepid individuals who make the best of the torquey little devil:

https://www.britishracecar.com/MichaelBartell-Healey-100M.htm

https://www.britishracecar.com/BillThumel-Healey-100.htm

 

[turtle]

P.S. a buddy took me for a ride in his 100-6 and it was charming. He had to work so hard shifting and revving his heart out; but he was having a ball. The engine sounded wonderful and was very exciting until I realized we never got over 35 mph. It was an exciting 35 mph. We switched to my car and it was a different experience. Tap the gas and away you go with a rumble. Not that one was better than the other but it was different. My car was built in 1988 and has a dreaded but ultimately welcome turbo hydromatic transmission. The car is a pleasure to drive and cruise around.

 

[drambuie]

Rick, You have done a very nice job with your upgrade, it looks like anyone could easily go back to stock with no fuss! But, after getting spoiled with some real horse power like that I very much doubt it! Thank you for letting us peek under bonnet. Just one thing, shouldn't their be stars and strips painted "under the hood" To represent American muscle? We can still call the "top side" with the shinny paint the bonnet! :eagerness:

 

[drambuie]

I don't understand the problem. I have 2 Big Healeys--a BJ8 and a BN2/100M--and I drive them everywhere (California--in particular the SF Bay Area where I live--has a bit of traffic). I also have a Mustang GT with 315HP and a 5.2-second 0-60MPH time. I don't drive the Healeys like I do the Mustang, where I have a lot of power on tap. I drive the Healeys with more planning and forethought; e.g. when attempting to merge in fast-moving freeway traffic I pick a slot in traffic that is moving at a speed that I can accelerate to in a reasonable amount of time. And, believe it or not, many if not most people understand you're driving an older, less-capable vehicle and 'cut you some slack.' They'll get impatient if you aren't doing 80 in the fast lane, but that's what the Mustang is for. It's like flying an airplane--you can get out of trouble in an F-15 by standing it on its tail and lighting the burners, but you can't do that in a Piper Cub, and you have to plan and fly accordingly.

If you want more pop in your Hundred, I've heard from reliable sources that a bore, higher-compression pistons, a Denis Welch head, larger carbs, headers and a hotter cam will give a 'stock' Hundred more HP than even a 100M.

I completely understand what you are saying, and that is the way I drive my Stock BJ8 rated at 150 HP. Now, with some Denis Welsh upgrades that would bring on at least 150 hp. That may be acceptable to me. But what REALLY bothers me personally is driving a vastly under powered sports car that looks like this....and getting beat up by a Honda Civic.

 

[HealeyRick]

Rick, You have done a very nice job with your upgrade, it looks like anyone could easily go back to stock with no fuss! But, after getting spoiled with some real horse power like that I very much doubt it! Thank you for letting us peek under bonnet. Just one thing, shouldn't their be stars and strips painted "under the hood" To represent American muscle? We can still call the "top side" with the shinny paint the bonnet! :eagerness:

To understand the under bonnet decoration, you need to read the story of "The Kingmaker":

 “The Kingmaker”


In 1965, this 1963 Austin-Healey Mk. IIA was converted by its original owner from street use to SCCA production racer. The car was stripped of its bumpers and weather equipment. Triple HD8 SU 2in. carburetors and manifold from the Donald Healey Motor Co., Ltd. were added, the cylinder head was ported and a BJ8 cam was installed. With the addition of a roll bar and aircraft seat belt, the car was ready to compete on the northeast road courses. Along the line, the Healey was treated to a color change from its original Healey Blue to turquoise with red wire wheels and rollbar “to better see it on track.”


It eventually followed the path of many old race cars, being relegated to autocross competition at places like Salisbury Beach, before being stored away in the owner’s barn. It was purchased in 1985 by the present owner, Richard Neville of Rowley, who restored the body and had it painted its original color. The Healey received a period “poor man’s Cobra” treatment, with a small-block Ford V-8 dynoed at 345 horsepower and five-speed transmission.


The name “Kingmaker” is a nod to Richard Neville, the 16th Earl of Warwick, who earned the title “Kingmaker” for playing a part in the deposition of two kings during England’s War of the Roses. The Neville family arms consists of a white cross on a red shield and is depicted on the underbonnet of the Healey. The Earl of Warwick’s home was Warwick Castle, located just down the road from the Donald Healey Motor Company, Ltd. and the castle is a prominent feature of the Healey badge.








 

[roscoe]

I'm completely happy with my stock motor (except for oil cooler, spin on filter and low lead valves and seats). I, however, am never in need of hitting 80 to get on the freeway. I've never thought of my BN2 as being wimpy. I never bother with first gear. With front disc brakes and mini-lite style wheels most of my freeway driving concerns have vanished. It's the other guy and crash-worthiness I worry about. I've always felt that the folks who take a look are often surprised that I can merge and keep up with traffic. When I first put it on the road I did take it a tad over 100 just to see if it was true. Never need to do that again. 65 to 70 is comfortable and safe if you stay out of the fast lane except to pass.

 

[drambuie]

Rick, thanks for the Enlightenment! I was wondering what your under bonnet symbol referred to..

 

[drambuie]

I'm completely happy with my stock motor (except for oil cooler, spin on filter and low lead valves and seats). I, however, am never in need of hitting 80 to get on the freeway. I've never thought of my BN2 as being wimpy. I never bother with first gear. With front disc brakes and mini-lite style wheels most of my freeway driving concerns have vanished. It's the other guy and crash-worthiness I worry about. I've always felt that the folks who take a look are often surprised that I can merge and keep up with traffic. When I first put it on the road I did take it a tad over 100 just to see if it was true. Never need to do that again. 65 to 70 is comfortable and safe if you stay out of the fast lane except to pass.

.

I too got my 67 BJ8 over 100mph and had more to go! But the front end began to feel dangerously light so I backed off. Won't do that again! But actually my 67 BJ8 is fairly respectable and keeps up with traffic very well. I too start out in 2nd gear sometimes as first gear can be too short legged in some situations. I had a 59 MGA coupe at one time, and swore I would never put myself in a dangerously under powered car again...almost got me run over more then one time! Horse power is safety to me!

 

[HealeyRick]

.
Horse power is safety to me!

 

[Keoke]

Yeah either of my 66 BJ8's will hit 100 MPH and not struggle to do it.

However, specified road speeds are generally adhered to.

 

[Bob_Spidell]

I completely understand what you are saying, and that is the way I drive my Stock BJ8 rated at 150 HP. Now, with some Denis Welsh upgrades that would bring on at least 150 hp. That may be acceptable to me. But what REALLY bothers me personally is driving a vastly under powered sports car that looks like this....and getting beat up by a Honda Civic. View attachment 41406

I know the feeling (getting 'beat up' by a Civic). Fact is, many of the 'hottest' cars of the '50s, '60s, '70s and even the '80s would get beat up by a lot of contemporary cars (the best 'muscle cars' of those eras would get dusted, too, and they can't corner worth a hoot). Some Ferraris of those eras only had 200 +/- net HP, and would get their clocks cleaned by some models of Lexus, Hyundia and certainly BMWs and Mercedes, and they'll all get their rear ends handed to them by a Tesla (up to 120MPH and a for a few miles, anyway). However, get the Civic that dusted you on the freeway on a windy backroad and watch him/her get scared, er, witless, and ride the brakes and wallow through even the slightest of curves. THAT'S when you can embarrass them.

BTW, one mod you may not want to do is the larger carbs. I now recall my 'reliable source' saying that the smaller H4s actually worked better with the other mods, as they keep the intake charge moving at a greater velocity. It's common for a shadetree mechanic to slap a bigger carb--it's a relatively easy mod--on his wannabe 'muscle' car, only to have low-end torque drop as the intake velocities decrease. This affects his ability to do burnouts, one of the silliest things you can do in a car IMO (and don't get me started on 'rolling coal').

 

[steveg]

...However, get the Civic that dusted you on the freeway on a windy backroad and watch him/her get scared, er, witless, and ride the brakes and wallow through even the slightest of curves. THAT'S when you can embarrass them...

Suppose this could be true with a really good Healey and driver against a poorly maintained 20 year old Civic, but I haven't found this to be the case on either the Angeles Crest Hwy or Hwy 330 from San Bernardino to Big Bear. My experience is pretty much every modern car is faster-cornering than our Healeys with their ancient bump-steering rear ends. A friend and I were driving to Big Bear on the 4-lane part of 330 with our tires howling and got easily passed by a mom in a mini-van who appeared to be talking on her cell phone.

Cruising: I have the 3.54 axle and Toyota Supra 28% OD trans with 180/15 Michelins - 3000 rpm = 80 mph

 

[MikeAH100M]

Vastly underpowered? That's the last description I would use for my stock factory spec 100M. The torque is more than impressive. The hotter cam, higher compression and larger SU's make a difference. Upgrading to a Welsh or other alloy head, roller rockers, tuned exhaust etc. would only add to that. A buddy is working on converting a basket case 100 and adding all possible upgrades including an all alloy body. My guess it will be quick and handle beautifully.

I have never had a problem keeping up in any traffic situation. I'd suggest you drive a well set up 100M before you make a decision. If you really want to beat a Honda Civic, than buy a beater vintage mini and drop a VTEC into it.

 

[drambuie]

Bob, I am glad you bring up that point about curves and twisting roads...so true! I can't tell how many times I took advantage of more powerful cars going into express way ramps and tight twisting roads, all of a sudden they get frightened and slow down as I actually accelerate into a curve and they disappear in my rear view mirror. It's always fun to WAIT at a stop sign at the end of the ramp and see the sheepish look on their face as they stop short of my passenger window to admire my Healey! EXCELLENT POINT! I have also read about the advantage of the H4s over the larger bore S.U. Carbs.

I have been trying to research real dyno numbers from people who added some of the Denis Welsh engine upgrades above the M spec cars but haven't found anything yet! You would think Denis Welsh would put forth real dyno numbers for people to see since they highly tout their high performance products! I do know the Healey Werks has some dyno charts on their web sight highlighting increased horsepower figures from upgrades such as fuel injection and so on. I also thought it was very interesting the Healey Werks offers a all aluminum block 3.8 version of the stock big Healey motor, but I haven't seen any dyno figures with this item dressed in high performance items. The reason why I am researching and considering upgrades is because I am planning a "special build " Healey and that includes high preformance suspension and 4 wheel disk brakes. I have already done this to a TR6 and the results where outstanding! Sorry I ever sold it!

 

[drambuie]

Vastly underpowered? That's the last description I would use for my stock factory spec 100M. The torque is more than impressive. The hotter cam, higher compression and larger SU's make a difference. Upgrading to a Welsh or other alloy head, roller rockers, tuned exhaust etc. would only add to that. A buddy is working on converting a basket case 100 and adding all possible upgrades including an all alloy body. My guess it will be quick and handle beautifully.

I have never had a problem keeping up in any traffic situation. I'd suggest you drive a well set up 100M before you make a decision. If you really want to beat a Honda Civic, than buy a beater vintage mini and drop a VTEC into it.

.

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...