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Comparative performance

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drooartz

drooartz

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Okay, folks, I've got a power question. As many of you know, I'm planning a 1275/5-speed swap for the Tunebug, to help with my mountain driving. In 2 weeks, I'll be at a point where I can get started. Before I make the final call and start spending money like I have it, I'd like to get a few opinions.

My real quandary comes from the fact that I don't know what sort of performance to expect from this project. The only LBCs I've ever driven for any length of time are the Tunebug and the TR4 I had briefly. How should the new engine compare with an MGB? A Mk1 Spitfire (with the 1147)?

After talking with Hap, I've got a good handle on what the cost of this project is going to be, and it's not an inconsequential amount. I'm not against saving up and spending it, but it does make me realize that I could afford a larger, more powerful car for the same cost. Yes, I've been down this road before, but I want to make sure I feel good about the final decision before I pull the trigger and start spending. I really want to be able to drive further than around the block, and these dern mountains are all around!
 
My stock 1275 (fresh rebuild) no real performance parts had plenty of power in my my heavy midget. I drove it up many long steep grades with other LBC's as part of club outings. I never held anyone up. Granted, I've never driven in mountains like you have, but these cars are fairly light and with the low gearing I can not see how a similar classic would fare any better unless it had a fresh engine rebuild as well.

How can you buy a bigger more powerful car with a rebuilt engine for the same money as it takes to rebuild a 1275? A strong 1275 bugeye with a 5-speed will runoff and leave a tired TR6 ... and look better doing it.
 
A bone stock 1275 has plenty of power for normal driving.
I had my stock 1275 Sprite out in the Rockies. Eisenhower pass, I hill climbed it at 8000-12000 ft and took 3rd place.
It did much better in the mountains than my Ford Taurus 4 banger. In that car I had to choose AC or up hill? Not both.
 
Trevor, it would require selling the Tunebug -- not something I want to do, but the thoughts do cross the mind when I add up all the numbers.

Mostly, I just don't know what to expect, and appreciate the comments. Tunebug is really slow with the current tired 948, and I have no experience with what I can expect power-wise from the rebuild work. I'm a Bugeye guy through-and-through, but also need to be very careful with my spending. I made some moderately costly mistakes with my foray into Triumph ownership, and I can't afford to make them again.
 
I live in the moutains and my 1275 with 52,000 on it had more than enough power, especially good on hills with the 3.9:1 rear gear. I did a re-ring job on it and new bearings and all since I had the motor out and all but we drove up to mount Mitchell with no problem except the overheating problem that I had and hope has gone away. Mount mitchell is the highest mountain in the Eastern US.
 
Drew,

I envy you with the Bugeye and your plan to increase its performance. If I were you, I'd charge ahead and never look back -- absolutely no doubt in my mind what so ever that you'll be very happy with the upgrades. Double -- maybe even 2.5 times -- the horsepower of the tired 948 and an extra forward gear along with it? No questions or doubts here!

I would leave the 4:22:1 rear gear in it and drive it that way for a bit before I considered changing differentials. I'd almost bet that the 4:22, or maybe the 3.90 will be in the car two years from now.

Best wishes with the project -- you won't regret it!

Tim
 
Sell it...Sell it...

I say this, Drew, as I think that you are not ready to accept the limitations of this car even with the addition of a 1275 and 5 speed. There will still be people passing you on the flats, and there will still be the need to downshift on some hills and grind up the grade.

These cars are noisy, smelly and cold in the winter and hot in the summer. They demand nearly constant TLC and even then, the top will leak somewhere when it rains.

They are as dangerous to drive as a motorcycle as you are 'invisible'. In a accident, you will lose. If a semi passes you he can push you to the shoulder or suck you into his slip stream behind his trailer. Not to mention meeting one at speed on a two lane.

Deer on the highway in your area? Notice how the front end slopes up to the windscreen.....

Sorry Drew. Just a few of my thoughts to confuse yours.

BTW...I love driving my BugEye.


PS to Spritenut...Eisenhower Tunnel...Loveland Pass. Used to use the pass all the time going skiing. In a '62 Sprite. A real good climb. .....1968.........
 
drooartz said:
I could afford a larger, more powerful car for the same cost.
Click to expand...
It wont put half as many smiles on your face, it won't be the Tunebug and you'll regret it for eternity.
You're putting a 30% (ish) larger motor in it, a super gearbox, larger carbs and it will be better than a factory 1275. That baby will fly!
The UK aint the great plains, there are plenty of mountains of impressive size, grade and altitude that these cars were well tested and driven on. I've driven 948 and 1275 minis up these mountains, and there <u>IS</u> a difference in performance.
If you're going to be a bear, be a grizzly.
You'll love it.
 
spritenut said:
A bone stock 1275 has plenty of power for normal driving.
I had my stock 1275 Sprite out in the Rockies. Eisenhower pass, I hill climbed it at 8000-12000 ft and took 3rd place.
It did much better in the mountains than my Ford Taurus 4 banger. In that car I had to choose AC or up hill? Not both.
Click to expand...

Never had to turn the AC off once in the Spridget did you?! Hehe /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
leecreek, I appreciate your thoughts and I do understand those things. I've been a motorcyclist long enough (10 years) to understand the "invisibility" problem, and I don't expect even the performance level of my daily driver Hyundai. I really enjoy the mechanical TLC time I spend with the Tunebug -- it's very therapeutic after a day spent with computers and numbers and such.

Thanks for the thoughts and anecdotes, folks. I'm just a few days away from fully committing myself to the Tunebug-upgrade path, and the words of encouragement are helpful before I take that plunge. I know that's the way I'm going to go, just needed one last chance to really look at all the options before I dive in.
 
I was expecting leecreek to ask you to give Tunebug to him after the list of pitfalls he pointed out to you Drew!! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
"Don't do that, give it to me!!" /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
Haha...I wouldn't do that....would I?
 
Drew
Even with a bone stock 1275 you will think (maybe true) that you have about twice the usable power of a 948. It will make Tunebug a useful car even in the mountains, and the 5-speed will make it great in the flats too.
Bill
 
Drew if we try to make these LBCs make sense, then it already a lost cause /bcforum/images/%%GRAEMLIN_URL%%/smile.gif The one thing a A-series engine offer over all over LBC is how quick they rev, then add to it the increased horsepower and torque of the 1275 when compared to 948. A little hint when messing with these cars, don't add up the cost, just do it, none of us really want to know what we have in our projects anyway /bcforum/images/%%GRAEMLIN_URL%%/smile.gif Any other LBC you would look at like a MGB or whatever with a uprated engine and tranny cost this much or more, A-series really in LBCs is about as cheap as it gets. You should see what parts for my buddy's Datsun 2000 cost, makes our cars sound like a bargain /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Dive, dive, dive. Oh wait that's a different movie.
 
Now now, I'm not giving the Tunebug away to anyone! Had a really nice day with my local car club (I was on my bike), and I'm getting motivated to get started on the list of projects. 14 months to go before the Spridget meet...

Thanks again for the comments, and I'll do my best to stop adding up the costs. Hard to do when you're the family financier! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]A little hint when messing with these cars, don't add up the cost, just do it, none of us really want to know what we have in our projects anyway [/QUOTE]

/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif oh how true that is /bcforum/images/%%GRAEMLIN_URL%%/whistle.gif
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif
 
It will be a big difference going to the bigger engine. 65 hp with a 1500 pound car is plenty, heck my wifes ford festiva weighs almost exactly the same and only has 63 hp and does fine in these hills. We do have to gear down from 5th to 4th coming up saluda grade from South Carolina but that is one heck of a grade and it still will maintain 60 up that hill. Someone was saying that there are alot of mountains in England and that is not really true, its mostly flat with some rolling hills, Scotland has some steep grades and wales doe to but England not so much. One of my friends had an old Morris panel van with the 950 and it was all stock and was a pretty weak engine. It came with a crank and you could start it by hand, no way you are gonna start a 1275 by hand.
 
When I first installed my 5 speed I asked Bill at Rivergate the best gearing for the bugeye and he said a 4.22 in the mountains and a 3.9 where it is mostly flat. After driving one for several yrs., I'd have to agree. I think even on a pretty steep grade you could downshift to 4th and still have the power you'd need. Also, there isn't many driving experiences like a bugeye, but each of hte forums probably say the same. I can only tell you from a lot of yrs. of experience that to do it right the first time is the least expensive way to go. Good luck!!!
 
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