which is faster?

ka · Post by ka » Tue Nov 18, 2008 8:38 pm

is a 712m noticably slower at accellerating than a 710m? i know the 712 has a lower geared tranny so its top speed is like 5 mph less, but i've only ever driven a 712amb and this 710m, never a 712m.

Jim LaGuardia · Post by **Jim LaGuardia** » Tue Nov 18, 2008 8:59 pm

The 710 accellerates faster and has a 10mph higher top speed.
The average 712 will go 55-60mph(screaming), while a good running 710 can exceed 70mph, That does not however mean it is safe to sustain.
At high rpm's the carbs cannot supply enough fuel resulting in melted pistons.
This is where injection changes the curve..................................

ka · Post by ka » Tue Nov 18, 2008 9:32 pm

whoa... a gr8 reason to go efi. art here drove jake raby's efi pinz and says my normal pinz runs just as good, but i'm seeing it really does not like cold. i'd also like to not have to bother with the elevation problem.

chapel · Post by **chapel** » Thu Nov 20, 2008 1:10 pm

A 710M feels like a sports car compared to the 712M's slowness.
greg

ka · Post by ka » Thu Nov 20, 2008 2:10 pm

well maybe i dont really want a 712 then. but isn't there an updated tranny available that has a gear for that extra top speed?

Badger · Post by **Badger** » Thu Nov 20, 2008 2:43 pm

ka wrote:whoa... a gr8 reason to go efi. art here drove jake raby's efi pinz and says my normal pinz runs just as good, but i'm seeing it really does not like cold. i'd also like to not have to bother with the elevation problem.

Elevation problem ? Cold ?

That doesn't sound good considering I'm thinking of traversing the Haute Atlas in winter - and will definitely be above the snow line for part of that journey ! Is this a significant Pinz problem ?

M Wehrman · Post by **M Wehrman** » Thu Nov 20, 2008 7:08 pm

Badger,
you will need the carbs jetted for the altitude,expect a power loss,but a lot of Pinz's came from Switzerland,it gets kinda high there too!

Jim LaGuardia · Post by **Jim LaGuardia** » Thu Nov 20, 2008 7:47 pm

For high altitude, reduce jets from 140 to 130, no lower than 125.
My injection computer compensates beyond 10,000 ft

Profpinz · Post by **Profpinz** » Thu Nov 20, 2008 9:27 pm

My injection computer compensates beyond 10,000 ft

Hmmm, we haven't got anything in Australia over 7300 feet..... other than planes etc!

Erik712m · Post by **Erik712m** » Thu Nov 20, 2008 9:29 pm

Hmmm.... We haven't got anything in Australia over 7300 feet!

I was 8000 this morning.

Use to around 1100.

Bruce Berger · Post by **Bruce Berger** » Thu Nov 20, 2008 9:59 pm

One reason I decided to go with EFI was that I have gone from below sea level to over 11,000 feet in the same weekend. In this part of California it's impossible to have the right jets in your carbs at all times.

andy · Post by **andy** » Fri Nov 21, 2008 8:51 am

ka, my 712 doesn't really "feel" slower than my 710 from a standing start.

I can leave the 712 in second gear to get rolling, like at a traffic light. The 710 wants 1st gear. Anything else requires lots (comparitively speaking) of clutch and lots of accelerator.

The 712 likes cruising at around 54-55 mph. It does not like to accelerate down hills, meaning my foot on the pedal hasn't changed, but gravity has set in and when it hits 62-63 mph the 4500 rpm light comes on.

The 710 just hums along and possibly because of the difference in weight doesn't pickup quite as much speed coming of a hill. No 4500 rpm problems there which is starting to make me wonder about the module. The 710 doesn't mind cruising at 55-58 mph.

My speed figures about cruising are based on where it runs without any obvious effort from my right foot to move it along faster.

It does seem that I go through the gears much quicker from a standing start in the 712 than the 710. To me that's the difference in the gearing.

Hope that adds to what you wanted to know.

Andy

Badger · Post by **Badger** » Fri Nov 21, 2008 11:29 am

In crossing the Haute Atlas it's quite possible, within the space of 24 hours, to go from sea level and moderate temperatures in Northern Morocco, to over 9,000 feet and snow, then descend down to around 2,000 feet and the heat of the approaches to the Saharan desert. In the desert nights temperatures drop to well below freezing. Is the Pinz really that sensitive to jet size ?

russ · Post by **russ** » Fri Nov 21, 2008 12:46 pm

Well, here in FL, I've driven to a few feet below sea level (in fresh water) to a whopping 190 ft above while traveling across the Sunshine Skyway Bridge and 345 ft above sea level at Britton Hill, the highest point in FL.

So how much silicon and liquid plastic is required to seal up that EFI for U-Boat use?

McCall Pinz · Post by **McCall Pinz** » Fri Nov 21, 2008 2:35 pm

My understanding is that if you're jetted for sealevel you may loose some power and burn more fuel at altitude, but that's better than jetting for altitude and running lean when you come down and burn up a valve.