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A decision made for more power

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drooartz

drooartz

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So I've made the decision on my power up needs... thought about TR3, MGB, Miatas (I know...) and decided that swapping a 1275 into the Tunebug is the way to go. Just like the car too much, and it's an inexpensive upgrade, and I've already got the car in hand, and my wife really likes it, and on and on. I'm slow, but I get the point eventually.

So I'll be building up a good street 1275 this winter. As I don't have one handy, I'll be on the lookout. What do I need to be looking for? Any blocks/heads better than others for street use? Looking for that balance of reliability and power. I've got the Vizard book, guess I need to start reading it!

Hap--anything you want to add? Once I have a block/head, I'll be in touch for tuning stuff.
 
I've thought about the blower, but in chatting with a fellow on spritespot who has a Judson on his Bugeye, I've become convinced that a 1275 is a simpler approach to power, with fewer cooling issues. With the heat here in the summer, combined with altitude/steep roads, I'm worried about drivability with a supercharger.

I still like the blower idea, and might hunt one down to put on the 948 once that is rebuilt in the future.
 
Frist Drew you need to get the book Tuneing BL's A-Series Engine by David Vizard. Try Amazon, mine is even signed for 20 bucks.

Read it then ask us what you need. All the answers are in it, and I mean all.
 
Got that book, just haven't really cracked it open yet.
 
There are few unique items in the 1275 production run like the EN40B cranks and such but for the most part for a street motor, it's no big deal any 1275 will work, most all of the heads (smog or non smog) flow about the same. So in short Drew not really just get your hands on one. You need some HS2 carbs, if you don't already have them on Bugeye. Let me know when you get ready to do this, even if you are assembling the engine yourself, maybe I can be of some help with the component prep. I'll clue you in on the best bang for the bucks parts, where to spend the money and where not to.
 
Drew, good luck, I know you've been stewing this idea for months, and in my most humble of opinions, you've made a great choice HP/$ wise.
If you keep your downflow radiator, you'll need to take the 1275 thermostat house off and put your 948 on.
 
I'm planning to find a ribcase to go with the 1275 for now. 5-speed in the future if the project grows in that direction.

Hap, I'll definitely be in touch once I get hold of an engine to start with. If I'm going to do this, I'm going to try to do the build as intelligently as possible. Wish I lived closer, so I could have you do the machine work that will be needed. Good club here local, so should have some good advice to find someone local.

Never done an engine rebuild before, so this will be new, interesting territory for me!
 
id go ahead and get a 5 speed.....the 4 is nice but after 60 mph u get up there in the rpms....no need to be repped out when ur traveling places.........z
 
My opinion:
The 5-speed conversion is going to cost some cash. It might be good to do it the following winter so that you aren't tempted to skimp on the engine build.
 
And.. used ribcase transmissions are pretty easy to find. Even if the syncros are slightly worn, you could use it for a year or so while you hunt down a 5-speed.
 
I'm not really looking for the 5-speed at this point. With finances tight, I want to concentrate on the engine as my main priority. Still hoping to find a good parts car with engine and tranny together.
 
parts car huh....youll be driving a midget before its over...haha...thats ok /ubbthreads/images/graemlins/wink.gif......zimmmy
 
When I restored my '67 I converted to 5 speed using the Rivergate kit. It uses a Datsun B210 trans and I have got to say it was one of the best upgrades I made to the car. I can now cruise on the hwy and not be caught by bicyclists. One of the best parts about the Rivergate kit is that it incorporates a rear oil seal into the kit.I know it takes away from the "Charm" of owning a MG but I do not feel bad about having an oil free driveway & garage.It also requires zero mods to the car or sheet metal to make it fit so it is completely reversable. Good Luck.. If you need any advise on the 1275 rebuild drop me a note.. I have a "Little" experience! Good Luck! John
PC070044.jpg
 
That's a nice looking engine bay!

I like the idea of the 5-speed, but it's not in the financial picture for this winter. One thing at a time.

And Zimmy, Tunebug will always be a Sprite, at least in my mind. Not that a Midget is a bad thing, mind you...
 
I was thinking the same way when I was drawing up the plans to build... Then I started checking ebay & other sites. I found the rebuilt trans and kit for $250.00 bucks!.. The guy I bought it from had put $1500 worth of 5 speed kit into a $50.00 car and then his engine died.. I even called Rivergate and verified that they had built the trans & kit for the guy. Guess I got lucky. Thanks for the compliment! John
 
drooo, i meant that youll find a parts car thats just a little too nice to scrap and end up driving it ; )
 
Zimmy, I've thought about that factor, actually. There's a guy in the local club with a RWA midget he's selling. It's partly dissasembled, with running engine and all body work done. I keep being tempted to buy it for the drivetrain and then sell the body shell and bits. I just know that I'd want to drive it, though, and I have no room for 2 cars on a permanent basis.

If I kicked my wife's truck out of the garage for another spridget, I'd have to go out with the truck, and it's cold here! /ubbthreads/images/graemlins/grin.gif
 
John--you got a great deal on that transmission kit! I'd figured about $1200 or so to put one in. Not bad, really, and since it is a bolt in, it shoudl be easy to do. Maybe next year, though I'll keep my eyes open for a deal to come along.
 
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