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Bob, The accelerator cable is not connected as I am trying to synchronize the carbs. I have had a frayed cable years ago. I'll check the fast run screws. I hope that's the problem. The thought on the spring was that a stiffer spring assuming 4.5 oz/in would result in a higher load being applied to the piston for a given vacuum so the piston would not rise as far due to the load applied. Martyn "Martyn Eastwood" 26448... MORE
Martyn... While there might be a slight change in power with great changes in altiude, this seems a "sudden" change according to your mails as well as one of great "extent" as well....at least this is the impression I am getting. So, I don't think the altiude difference accounts for the problem you are having, For things to suddenly change to this extent...I'd be looking for something pretty obvious like a frayed accelerator cable which can "hang up" in it's travel (just replaced my choke cable today for this very reason), etc. Wish I was there to see it... MORE
Listers, one and all. For the past few years we've had a group of enthusiasts gather in Madison WI (USA) for a bit of post-Thanksgiving turkey Sprite dismantling and/or rebuilding called Save Our Sprites. These "events" take place the Friday and Saturday after Thanksgiving (Nov. 28,29 this year) and are viewable over the internet through some video magic. (details later) We hope to improve that this year with faster service for better interaction. In the past, those who wanted to contribute, but couldn't attend, offered food and beverage from their locality. We've had some great variety from scrapple to... MORE
Martyn...you misunderstand. The spring over the air valve in the SU carb determines mainly when the air valve reaches the full open position with respect to "redline" assuming all other things equal. This is it's only purpose. As cam profile duration and lift increase (over "stock") so shall vacuum produced by the engine at lower rpms DECREASE. IOW......at lower rpm (idle) the engine will "suck" LESS, all else being equal. With respect to your problem, vacuum in this case is working FOR you, not against you. Make sure your throttle return springs are properly hooked up and that the... MORE
Setting the ignition timing made a big difference, it now idles at 1500. I believe that the VP3 cam is causing a large vacuum and the pistons are being raised more than is normal. Cap'n Bob suggested using a stiffer spring in the carbs. Those are on order so next weekend should be the final step in getting the beast sorted. I put 30wt oil in the dampers and that helped with the piston oscillations but they are still more open than I think they should be. Am I correct in thinking the stiffer springs are the right solution... MORE
(still in the box) clutch MC. I purchased the slave and MC, and only needed the slave. Again, thanks in advance for any further words of advice. Later, Pete 78 midget Granville, OH "Pete Skalski" 26422... MORE
There are 4 gears floating around in there. The Big gear that drives the axles, a little gear that comes in from the driveline and 2 other gears that transfer the power from the driveline to the axles. Any one of them have a broken tooth, and it is time to say, what is your gear ratio. 3.9 to 4.22, swap rear ends, 3.7? or 4.55? what is it worth to stay at this gear ratio? 5.?? You are in trouble. Bob, Troutdale, OR "Robert Webb" 26411... MORE
I percieve, Bob. We had gotten reports here on the East Coast that two guys were seen spreading some sort of accelerant around before lighting a fire....obviously, not the case, thank God. Seems to be a case of everyone else at the other fire, when the "other" fire (in your area) got out of hand due to a "coincident" wind coming up compounded with yet, a Santa Anna wind event...bad timing, bad circumstances. Bad news in any case, of course. At least I hear they are getting it under control.... bad one. Cap'n. Bob '60 :{) PilotRob@... 26388... MORE
Bob.... Go with an alcohol/water mix (60/40) and I am quite sure you could run up to 8psi boost on 9.4 with no problem but, you're gonna be far better off running both the foregoing along with an ignition retard system or, limiting advance to something like 24 degrees on a regular mechanical advance distributor considering the best you can get in terms of pump fuel will be 98RON unleaded. MSD makes an excellent boost retard ignition system and I am sure Aldon over there has some ideas in this respect as well which may very well consist of... MORE
yes. Different crank and rods (inferior metal, but larger big-ends). Front mounting plate is different (and a mod to the oil pan too I believe) Oil filter is spin-on on the side of the block pointing upwards somewhat. low comp pistons I think. Single row timing chain maybe (OK, I am struggling to recall after the 1st three items) The A+ out of the Ital has a ribbed block, so that is good... Mike "Mike Gigante" 26375... MORE
Ed... This is strictly a matter of density altitude or to put it differently, the amount of air molecules per cubic foot of.....air!! The air at 10,000 feet is much "thinner" than the air at sea level...it is much "lighter" per cubic foot. Fr'instance, at sea level a cubic foot of air weighs 14.7 lbs. It weighs half of this at an altitude of 18,000 feet. The adiabatic lapse rate (temp. change per thousand feet) and it's humidity figure into this but we'll ignore these for now. So for the volume of air taken in at 10,000 feet, you... MORE
Which makes/models are suitable for conversion to electric motor power? (i.e. use it as a 'glider' for an electric car) Thanks for all responses. Also, check out this little DIY alarm-pager-intercom on Ebay now: Item no: 2439666572 "xxxrs2003" 26331... MORE
Yes, Martyn...agreed. Assuming the cam is properly timed in in accordance with previous post, I would at this point expect an induction leak(s) of some kind. VP3 cam or not, the engine should be capable of reduced idle to the point the engine will quit, though in reality 1,000rpm is a more realistic setting with this cam and even then, it'll be pretty lopey, even in a 1275. Not a displeasing sound though, IMHO!! :) Spraying carb cleaner (be careful) in and around the induction system should tell the tale in this respect...the idle will immediately change if and... MORE
Bob, Well... You're right what skews my thinking is that many years ago I had a worn timing chain that was so bad the headers would glow red as the engine speed increased. BTW the chain is new duplex with vernier gears. In order to get it to idle 900-1000 I had to retard the timing (rotate the dizzy ccw). The idle screws would have no effect on the speed unless I did that. Does this mean I got some leaks around the carb shafts? I'm going to go back and static time the ignition and see where it's... MORE
I know this is basic but maybe it will save someone else a lot of frustration. The previous owner of my car had installed a Pertronix distributor conversion on my 1963 1098cc Sprite. No other modifications; no new wires, coil or plugs. Since I drive this car to work every day, I decided to replace all of the basic electrical components; relay, fuse box, spark plug wires etc. I also decided to replace the Pertronix unit with a new one AND their coil. Having accomplished all of that, the car ran hot, stumbled until it got warmed up and... MORE
If it is the altitude thats causing this sluggishness, which it sounds like, try switching to leaner carb needles and springs. Nigel "amukdigiphoto" 26318... MORE
Well... Sounds to me like you've got ignition timing mixed up with cam timing. The cam timing can be "staight up" or for a little heftier lower range at minimal expense to the top end, timed in no more than 4 degrees "advanced" per Vizard's recommendation. Assuming you are using a new timing chain, after initial chain "stretch" the cam will end up running 2 degrees advanced...perfect! For your application considering a small bore engine, and "long stroke" at that, I'd go "straight up" for the track, 4 degrees advanced for the road, most especially if you're planning to... MORE
The 1098 has a long stroke relative to its bore, so with VP3 cam I expect it would be more 'lumpy' running engine.Especially at low end of revs and not particularly a fast revving engine either (not knowing what else has been done to the engine of course) Don , Part Scotch , nah !!!. Scottish maybe but not Scotch, scotch is whisky !!! Depends on how much you have drunk over the years I suppose, then you could be part scotch !!! 8o) Jaeger , not English or ever made in England as far as I know, but... MORE
I live in Northern Nevada, near Reno. The car is sluggish and can not be trusted to be a good driver. It sputters between shitfts and does not get to speed. thanks "ooohaynow1" 26309... MORE
VP3 cam...oh, yeah!!! Martyn, this is about as hot as you can get for the road in a 1275 and still have decent low end for light to medium traffic. In your smaller 1098, it's almost a mild race cam! Hopefully, you have the larger main bearing "cc" engine because this cam's torque curve comes in at about 3200 on a 1275cc+ motor and will pull right through 7,000rpm with larger valves and 1.5 rollers. On my 1340, it would idle very nicely at about 1,000rpm (nice "lopey" sound) and behaved very well using a 45DCOE with a Weber... MORE
My Brother-in-law just bought a 72 Citroen DS 21, the gauges are Jaeger Electronique. . . . It like ridding on air sitting on overstuffed living room couches. It has a central hydraulic system that runs the suspension, transmission, power steering and brakes . . . an inch and a half round red warning indicator is in the center of one of the gauges labeled "STOP", needless to say it is the hydraulic failure indicator. Being Scotch, Irish, French and German, and who knows what else I have a broad range of folks I can be politically incorrect with.... MORE
The noise from the left hand bank of speakers is a bit muffled, needs sorting a bit, but otherwise coming over loud and clear. R. "Roger Stinson" 26269... MORE
To my spark plugs that is! I've replaced the points and wired them correctly, new rotor, cap and wires. Still no spark, I'm lost as to the problem. The points have voltage on the outside contact when open and voltage on the inside when closed, referencing the shaft as the inside. I checked the wire to cap connection with an ohm meter everything's good there. The coil gets power when the points are closed, the coil is new also. Does anyone have an idea as to what I've over looked? Thanks. "Martyn Eastwood" 26273... MORE
G'day Cap'n I think it's RON. There is only one octane measurement over here, down under. And yes, it's unleaded. With one of those in-line zinc fuel catalyst thingies to protect the valve seats. avagoodday Colin "Colin@SpriteParts" 26237... MORE
G'day Alan et al Can't help with the combustion chamber volume. The kerosine keeps running out those large holes where valves should be! The combustion volume depends on (amongst other things) how "proud" the valves sit off the seats. And since the head has no valves, and I have no new valves to try in it, and since I don't feel like buying two new valves - I can't answer your question! But I do know I have machined over .100" off head faces before exposing the oil feed line. With the higher comp pistons available, it's unlikely you... MORE
