Question for a friends Bugeye

Hi guys, I'm new here (for a good friend) and have some basic performance questions about a '58 Bugeye. The car has the 948cc motor and it's all stock. Can you list a few tried-and-true measures he/we can take to bump performance a bit? He's really only concerned about it's relatively low 60mph highway speed.

I was thinking along the lines of rejetting the carb, better plugs/wires, larger carb, good air filter etc. He's not yet to the point where he's willing to swap motors, go to larger pistons etc.

Looking forward to any help he can get!

Your friend may boost power with more carburetion. But his concern will also be cruising RPMs. There are 5 speed Toyota conversions. To push the taller gearing higher compression for more torque is wanted. My 948 Mini would go faster than 60 mph but the old engine was beating itself up over that for any length of time. I added dual carbs and promptly blew the head gasket. In short there no easy way. Cheers Ron

In reply to rconlon:

I would be thinking Rotary, 2.0 Ford, etc. but that's out of the question right now.

I'd try to source a bigger A-Series engine (1275cc), drop that in and keep the original block around. To properly freak out the rivet counters, put a BMW K100/K1100 head on it...

I had a '59 Morris Minor with a 948cc A series engine. Probably the best thing I did was to put taller gears from a later MG Midget in it. The gears sets are all interchangeable, between Morris Minors, Sprites and MG Midgets, all years. But you have to watch out for the missing gear oil fill hole. With the MG diff. gears, I had to pour gear oil down the axle tube to get oil into the gear case.

I also put a ported head from a 1098 motor on it, with a modified MG Midget Exhaust tube headers and twin 1 1/4" S.U. carburetters.

The rest of the engine was stock. I could get the speedometer needle to start another lap with that set up. The Morris speedometer only goes to 80 mph. A friend with an accurate speedometer paced me at 90 mph, the Morris's speedometer needle was pointing straight down to the gas gage.

It could cruise easily at 70 mph.

Dave

I have a '59' I swapped in a built 1275 (1380) and a datsun 5 speed from rivergate. its a spunky little car that will go over 100 mph now ;)

I just found out it has a Weber downdraft on it.

Hmmmmm...

downdraft?

KaptKaos wrote: downdraft?

Well I was told (I've never seen it) that it has a Weber downdraft carb on it. Maybe it's a SIDEDRAFT?

It's hard to tell what you meant by "". Emoticons don't tell me much.

I thought most folks put side drafts on the A-series, but I could be wrong.

It's easy to tell the difference. With a downdraft carburetter, the air flow is down towards the ground, it makes a 90 degree turn through the intake manifold and into the engine. With a side draft carburetter, the air flow is sideways and goes straight towards the engine.

A Webber downdraft carburetter is an aftermarket part on a Bugeye Sprite. They look like a regular old carburetter, not sexy at all. Stock was a pair of 1 1/8" SU carburetters, they are side draft carburetters.

If you buy a shop manual for the car, it will have no information about the Webber downdraft carburetter.

Have you looked under the hood of your friend's car? If not, maybe you should.

Dave

For clarification, when I think of downdrafts, I think of the IDF/IDA range of webers, not the DGAVs and the like. It could be my misunderstanding of the DGAV-type models.

DneprDave wrote: Have you looked under the hood of your friend's car? If not, maybe you should. Dave

He's aware (as am I) that the carb--whatever type it is--is an aftermarket carb and that it came with SU's.

And no, as I said in my previous post, I've not seen it. I'll get over there one day and check it out.

Plus, I'm pretty sure there's only one "b" in Weber. But anyways...

I have a neighbor named Webber, I always make that mistake when writing about carburetters. Sorry!

Dave

In reply to DneprDave:

What a coincidence... I have a cousin named Quadrajet!

There is the clue to the poor top speed that we needed. I bet the Weber is holding back the engine. I had assumed you had the stock dual SU set up. So... get a modern set of dual carbs appropriate to the car and that might satisfy your friend.

Cheers Ron

In reply to rconlon:

Well that's interesting! I would've thought that it flowed more fuel than the SU's. Shows how much I know!

If he did that (went back to stock duals) and they were professionally adjusted, would it stay that way for long? Or maybe one of us needs to become adept at working on those carbs?

Thanks for the help by the way...

Once set up and synchronized, S.U. carburetters don't need further adjustment. Unless you fiddle with the throttle linkage afterwards, they will stay in synch.

You do have to remember to add engine oil to the dashpots on a regular basis.

If you get the Bentley publishing shop manual for the car, it will have all the information necessary to adjust the carburetters.

Dave

My guess is the carburettor is not operating well or it is not appropriate for the engine. Both SU and Webers can do the job. The Sprite should top out at around 80 mph. What is the condition of the engine? It needs to be in top form before considering upgrades. Cruising rpms are another issue.
Cheers Ron

In reply to rconlon:

I'm going to get some answers about: #1 condition (which I believe is very good but I'll know for sure soon and #2 what model Weber it's got.

Thanks guys!

Normally, after market Weber carbs are kits that fits all, and same carb is used that fits all, and they are never jetted correctly, and owners usally can't, or don't, figure out how to get full throttle. In reply to Bugeyefriend:

Have your friend send a pic of the engine compartment to you so you can show us.