Engine conversion

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Jim LaGuardia
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Re: Engine conversion

Post by Jim LaGuardia »

I laugh every time someone wants to re power to go faster :lol:
The 710 will easily cruise at 62-70MPH when properly tuned. However, the faster you drive it takes it's toll on wear items, after all it is just a 70MPH 4wd tractor. If you can't live with that, you need to find another vehicle.
As for engine improvements, there are better pistons and camshafts to compliment or enhance the driving/performance of said tractor.
I have yet to see a viable alternative to a modified factory engine :shock:
Cheers, Jim LaGuardia
http://smg.photobucket.com/albums/v510/Goatwerks/
"Arch Magus of Machines."
spandit
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Re: Engine conversion

Post by spandit »

The brakes are scary enough with stock power - wouldn't like to speculate what would happen with 400bhp from a big V8!
--

Robin

Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
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westernair
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Re: Engine conversion

Post by westernair »

Personally I am more than fine with the 70 mph, just would like to maintain it a little better when driving the Washington highway hills. I have near daily driven air cooled VW's for over 20 years now. I am use to driving at 70 or below. I do build up stock VW motors so when crossing over the mountain passes and the such, I can keep the speed up to 55 or so.
I am not a hard core off roader; I am more of a trail driver with my truck, so pushing it to its limits off road is not an issue with me. A 2.7 L upgrade to me seems like a very very good option.
Shawn

62 haffy Bantam
61 haffy 4 door

72 710K - Sold
73 712M - Sold
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Re: Engine conversion

Post by Winter Beater »

Those with the mods already could probably answer this:

Will the 'enhancement' of an extra 200 cc and a cam allow the pinz to hold 55 up hill? And could it rev above 4500 rpm? My 712 runs fine on the flat 62 MPH@ 4200 rpm (5800 ft elev Denver), but I would certainly consider modifications to let me handle small elevation changes without losing 10 MPH. Even underpasses on the interstate over rev the engine on the way down and slow the Pinz coming up the other side.

What would the parts cost for a 2.7 conversion? I don't burn oil and the engine seams tight; do I also need bearings and cam?

Is the conversion as reliable as stock?
Jim LaGuardia
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Re: Engine conversion

Post by Jim LaGuardia »

It's not so much the bore size as it is the compression ratio and type of pistons used, and cam grind. I prefer "square" engine builds (94mm stroke, 94MM bore) @8.6:1 compression
The stock 2.5L factory torque curve shows power output peak at 3800rpm.
My 2.6+L High torque engines pull peak sustainable power up to 4100+rpm . This power curve works well on grades, it is a noticeable improvement and reliable.
You can go without the cam and still have some performance gains on grades from the higher compression pistons, but it is notably better with the cam.
Cheers, Jim LaGuardia
http://smg.photobucket.com/albums/v510/Goatwerks/
"Arch Magus of Machines."
Erik712m
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Re: Engine conversion

Post by Erik712m »

From my experience. EFI 2.5L and a buddy with 2.7L I slowed to 20 mph around the Eisenhower Tunnel and he was in the 30 mph range. nether were going with the flow of traffic.
Jim LaGuardia
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Re: Engine conversion

Post by Jim LaGuardia »

It sounds like the 2.7L you mentioned has a stock cam.
The modified cam is key for climbing grades, an engine needs to breathe under load and the stock cam cannot do that at higher rpm's.
I would also do a compression check on that engine as it should be above 150-160PSI.
Basically the more torque generated, the better an engine performs on hilly terrain.
On the subject of RPM limitations, Redline between a stock engine and a modified engine changes due to the type of piston material used and carb settings.
The stock cast aluminum pistons will eventually fail above 4500rpm for extended driving due to material heat transfer(melting). A forged Piston is lighter and can take more heat, moving actual redline into the 5500+ range, but at that point you are at the limit of the connecting rods and float bowl capacities(read running lean ).
My mods put the engine safely at 110-125HP, a noticeable improvement and within the max engine output for the drivetrain.
Bottom line, if you need more power and the engine is tired, it is only a few more $ to upgrade.
This week I shipped out a set of my 2.6+L pistons and high torque cam to a list member up north.
I am sure he will post results after his truck is back on the road :wink:
Cheers, Jim LaGuardia
http://smg.photobucket.com/albums/v510/Goatwerks/
"Arch Magus of Machines."
Erik712m
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Re: Engine conversion

Post by Erik712m »

Jim probably right on the cam. I was planning on doing the 2.7l conversion till Herbert fell ill. With no one around here to really do the work. i decided it was time to sell.
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Jimm391730
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Re: Engine conversion

Post by Jimm391730 »

When Jim L. finished his cam/pistons/2.7l conversion in my W, we took it to a local steep road near Jim's. He said that many sad engines have trouble getting up the hill in third gear. We accelerated up the hill and I got into fifth for quite a distance, but couldn't quite make it to the top without downshifting to fourth - but remember, my W weighs almost twice as much as a 710M! (Yes, I know the gearing is 12% lower, too, but with Jim and myself in the truck we were at about 7800 lbs). This means my engine has to produce 55% more power than similar stock engines, and Jim was seemed pleasantly surpised at the performance. Jim, if I didn't recall this right please correct me.

I must say that his engine conversion has made an amazing difference, and has been trouble free for the last almost 4 years.

While my 710M is much lighter in weight, it burns no oil so I am not ready to upgrade it yet, but when it's time comes it will get Jim's treatment.
Jim M.
712W and 710M
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Re: Engine conversion

Post by Winter Beater »

I think I'm sold. 2.7L first then EFI. Need to start making a plan.
krick3tt
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Re: Engine conversion

Post by krick3tt »

Any man who thinks he can be happy and prosperous by letting the government take care of him:
better take a closer look at the American Indian.---Henry Ford
Jim LaGuardia
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Re: Engine conversion

Post by Jim LaGuardia »

Those are Ross pistons. Judging by the carbon build up, it was running rich or burning a bit of oil.
I would guess if they were from a Red Bull truck they are 95.5MM bores or 3.755", that is the bore size used on most of them.
Cheers, Jim LaGuardia
http://smg.photobucket.com/albums/v510/Goatwerks/
"Arch Magus of Machines."
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westernair
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Re: Engine conversion

Post by westernair »

OK outside of this auction where does one buy a set of pistons, jugs, and cam to do the conversion? Also does anyone (maybe Jake Raby) make a stroker crank? I usually build my 1600 cc VW motors up to 2110cc .. Bore 90.5mm .. Stroke 82mm then a 430 Lift / 284 Duration cam. On a VW based motor stroking it gives the motor more tork.
Shawn

62 haffy Bantam
61 haffy 4 door

72 710K - Sold
73 712M - Sold
Jim LaGuardia
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Re: Engine conversion

Post by Jim LaGuardia »

At 94mm, the engine is already a stroker. I use your cores(cylinders, cam , lifters) , all boring, piston and ring fitting are done and pistons are installed into the cylinders so you need not wory about damaging or positioning a ring.
Cams are re-profiled, straightened, heat treated and have threaded end plugs, lifters are resurfaced. This cam grind enhances torque curve and output.
Without the cam, you will only gain larger displacement.
Cheers, Jim LaGuardia
http://smg.photobucket.com/albums/v510/Goatwerks/
"Arch Magus of Machines."
yaknowthatguy
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Re: Engine conversion

Post by yaknowthatguy »

I, for one, welcome our 2.7 liter overlords.

especially since I just got my 2.7 build from Jim L.....and am salivating to get it put in my truck. soon...but not soon enough!
712 amb. under construction.
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