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Old 06-26-2008, 03:31 PM   #16
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I have a V-Spec that I call "14+2"

I raced it for 14 gallons,(with zero major issues) and then rebuilt it after its 14th Gallon. I re-sized the sleeve, replaced the C-rod & replaced the stock bearings. It is now on its 2nd gallon on the rebuild, going super strong. Raced it last Saturday, and was ballisticly fast with consistent tune all night.


I'm currently breaking in a New 08 V-Spec. (Same method) My 14+2 is going to become a backup motor after this last gallon.

I know of a half of dozen V-Spec with over 10 Gallons on them in my area.
I've only got a few gallons on mine, should i replace the con-rod soon ?
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Old 06-26-2008, 03:32 PM   #17
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Or wait till after i pinch it ?
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Old 06-26-2008, 04:06 PM   #18
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I have a V-Spec that I call "14+2"

I raced it for 14 gallons,(with zero major issues) and then rebuilt it after its 14th Gallon. I re-sized the sleeve, replaced the C-rod & replaced the stock bearings. It is now on its 2nd gallon on the rebuild, going super strong. Raced it last Saturday, and was ballisticly fast with consistent tune all night.


I'm currently breaking in a New 08 V-Spec. (Same method) My 14+2 is going to become a backup motor after this last gallon.

I know of a half of dozen V-Spec with over 10 Gallons on them in my area.
Wow Im very impressed! I have never heard of a vspec lasting that long. I have heard some that will go 9-10 gallons but even those seem to be few and far between. I have always stayed away from vspecs because the guys that run them at my track (who are really good tuners) only seem to get, at best, 7 gallons out of them. If your willing to share your break in secrets maybe I will try one.
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Old 06-26-2008, 04:07 PM   #19
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I've only got a few gallons on mine, should i replace the con-rod soon ?

IMO, Replace the C-Rod only when needed. And that means when there is slop between the Rod and the Crank Pin. Make sure if there is slop what part has worn. Sometime when there has been massive uses the crank pin can and will & wear out too. .194''-.193" is the OD of a V-Spec Crank Pin in good condition. But take care to measure it at the 3 & 6 O-Clock position. That is where it wears out the fastest. At 12 & 6 O-clock will always wear less then on the side strokes.

When I take mine apart for cleaning and inspection I place the C-Rod on the Crank (Out of the motor) and feel for play and measure then to determind what part should be replaced if needed. Typically you can get away with a couple .002" wear, but any thing more it should be replaced IMO. Other wise massive motor failure can occur.

Good luck
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Old 06-26-2008, 04:19 PM   #20
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Wow Im very impressed! I have never heard of a vspec lasting that long. I have heard some that will go 9-10 gallons but even those seem to be few and far between. I have always stayed away from vspecs because the guys that run them at my track (who are really good tuners) only seem to get, at best, 7 gallons out of them. If your willing to share your break in secrets maybe I will try one.

Baisicly the same old school "Heat Cycle" method.

I start off taking my time running the motor on the slightly rich side slowly increasing the power till I reach 100% throttle. That is typically around the 10-12th break in tank. Then I start to tune for race performance. Each time I start the motor cold, I will use a heat gun to preheat the motor to 200+ degrees (F) for the first 2+ gallons or till I feel that 100% of the metal to metal pinch/friction is gone when starting cold. Preheating insures there is zero stress on the workings of the motor when starting it cold. Makes a huge difference on the longevity of the motors overall life. Thats very important IMO!! I will also use a good amount of After run oil before its first few tanks to make sure there is plenty of lubrication on the working parts. I also use a clean Air filter every time I race.

When racing I always make sure there is a light blue smoke trail throughout the entire power ban. I don't really pay attention to the temps, but it usually runs in the 220-240 range. In the Summer it would get to 280 occasionally , but still had/has light smoke and it is 100+ degrees (f) outside. After each race, I run out the rest of the fuel in the tank, fuel line, and motor. After that I use After run oil, and bump it on the box to coat the workings good. Oh.. after each practice, heat or main I ALWAY move the piston the BDC still to this day. Habit now. That way when it does cool down the piston is totally clear of the top of the sleeve.

After every gallon of racing I will completely take the motor apart, for cleaning and inspection. Soak all of it over night in D-Alcohol, & completely clean and re-seal the motor up with "Air Seal" after re-oiling.


Seams like a lot of work, but really its easy, and is a habit now for me.


Good luck and good racing!

Steve
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Old 06-26-2008, 04:31 PM   #21
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Mine died after 4 gallons. Breakin was done by a pro in our area. I found out later that the JP4 pipe puts too much back pressure on the motor (straight from an Ofna racer) and it heats up the motor. Basically I either need to pinch it or replace the P/S.
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Old 06-26-2008, 07:17 PM   #22
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Originally Posted by Steve Walters View Post
IMO, Replace the C-Rod only when needed. And that means when there is slop between the Rod and the Crank Pin. Make sure if there is slop what part has worn. Sometime when there has been massive uses the crank pin can and will & wear out too. .194''-.193" is the OD of a V-Spec Crank Pin in good condition. But take care to measure it at the 3 & 6 O-Clock position. That is where it wears out the fastest. At 12 & 6 O-clock will always wear less then on the side strokes.

When I take mine apart for cleaning and inspection I place the C-Rod on the Crank (Out of the motor) and feel for play and measure then to determind what part should be replaced if needed. Typically you can get away with a couple .002" wear, but any thing more it should be replaced IMO. Other wise massive motor failure can occur.

Good luck
Thanks, i've got a big race Saturday so i'll take the crank out next week.
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Old 06-27-2008, 02:45 PM   #23
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To be honest I have lost track of the amount of fuel that's been through mine.
It was bought in August last year, and as we race pretty much year round here every 2nd weekend, it's done some serious mileage. There are some 2-3 day meetings in there, and even on club days in winter we have 3-4 rounds of qualifying and 30 min A mains.

Mine I believe is a 2006 spec as well which were meant to be bearing eaters.

The only thing I've done to it is replace the rear bearing in it, it's still on the original front bearing, rod, sleeve, piston, the lot!!!

This engine has been amazing, it still starts easily, idles forever, has yet to flame out once in a race and will still drag my 4.7KG Hyper ST down the straights as fast as Collari Novas, O.S. Speeds, and even the new GRP's (my next motor) with the 8MM restrictor in it, and I've managed up to 10:15 run time on a tank....

I know if the GRP doesn't perform as well and get better mileage I'm going back to O.S.
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Old 06-27-2008, 03:18 PM   #24
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Oh and BTW, my break in method:

Pre-heat the engine, start it, wrap some foil around the head, drive it.

I usually do this in the street. Start off with small throttle openings and just blip it driving around in figure 8's. Check the temps regularly and I like to get it to around 200*.Work with the mixture screws to keep to this temp. I don't have the engine super-rich either, it should be blowing plenty of smoke yet not 4-stroking or bogging excessively. Do this for a tank, when the engine stops remember to make sure the engine is at BDC.

Repeat.

Then I will start using a little more throttle. Once the engine is up to temp I will use up to around 1/3 to 1/2 throttle and start letting the revs build up a bit for short bursts. Then the next tank, let it run a little longer on the bursts - still at small throttle openings so it won't rev to the moon or anything.
Again, keeping an eye on the temps, amount of smoke etc... and letting the engine cool down after each tank with the piston at BDC.

Next step is to start pulling a few full throttle bursts, short stabs, for maybe a second or so. you may have a few mixture issues here but you want to get it so it accelerates fairly cleanly with minimal bogging but still plenty of smoke. Check the temps!!! You may even find you have to start leaning it out more as there is more fuel going through the engine here and remove the foil.
Do this for a few tanks, increasing the frequency of the stabs at the throttle.
During this stage I vary the load on the engine a lot. I'm not just idle - full throttle - idle, I've normally made a 'track' I follow on the road. "Up the curb over there, head down the footpath, around the tree, up to the mark on the road there......"you get the idea? So I'm using all the rev range, and a variety of throttle loads except for extended high rev periods.

I will do this, slowly leaning the engine out as I go until I've run through about a litre of gas.

Then I will head to the track, and start racing it. It will take another couple of litres to start coming alive and really sing, but it's safe to race.

I have tried almost every method thinkable and this works best for me and my engines.

A few guys I know now use my method and they too have had really good strong engines that last well.

Wow... that was a bit longer than I intended.... hope it hasn't bored you all
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Old 06-30-2008, 07:55 PM   #25
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Originally Posted by stiffler297 View Post
Mine died after 4 gallons. Breakin was done by a pro in our area. I found out later that the JP4 pipe puts too much back pressure on the motor (straight from an Ofna racer) and it heats up the motor. Basically I either need to pinch it or replace the P/S.
Hey guys I'm new to RC Tech and have been cuising arround looking at all the great info. I only started racing this year and have allot of learning to do yet. While engines seem to present a pretty steep learning curve for me I'm starting to gain some ground. Since the beginning of the season I've been running a Vspec in my truggy and I've been very happy with it. Easy to tune pleanty of power everything I could ask for. Until the other day I've been running a JP-3 pipe. I just bought the new JP-4 pipe and moved the old JP-3 to my spare (backup engine). I noticed stiffler297 posted that the JP-4 is not a good pipe to run on the V-Spec. What is is this based on? Have you all heard this somewhere else? I was told that the JP-3 and JP-4 are very similar. What's you all's opinion?

I also noticed recently on the Amain web site when pricing another Vspec they make this statement. "May be run with up to 30% nitro fuel without reshimming the engine, but an extra shim is included if you wish to add it to run 30% nitro fuel." Does this make sense to you?
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Old 06-30-2008, 08:04 PM   #26
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i was able to get 9 gallons easy through my Vspecs...thats with race tuning, basically 5 minute warmup, tune, 2 to 3 5 minute heats, then a 20+ minute main...zero issues, zero flameouts, consistent tune.

once your tune starts to be erratic, thats a sign for a rebuild or new motor. im sure i could still run my motor, but its not worth it at that point, 9 gallons has paid for the motor and some, JMHO.

i do the old heat cycle method that Stephen Bess posted a while back on the grid a couple of years ago. Im tired of wasting a gallon for breaking in my engines, thats one of the best attributes that these engines carry, ease of break in...i probably go through 8 truggy tanks (overkill) of heat cycles and im 100% ready to rip. i go right to race tune...running your engines overly rich combined with cool temps isnt exactly ideal. here is a link to the break in procedure i use on every engine i have ever owned, and it has been awesome!

http://www.momentum-rc.com/joom/inde...news&Itemid=50
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Old 06-30-2008, 11:55 PM   #27
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That Steven Bess method sounds very similar to mine. Works fantastic.

Idling on the starter box is the biggest waste of time and fuel I know of.

My engines outlast anyones I've seen use that method.
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Old 07-01-2008, 07:55 PM   #28
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yea, everybody has their own methods (as some have excellent luck with the idle on the box method or break in stands)...i think the biggest factor while breaking in any engine is getting the piston & sleeve to expand at operating temps and allow it to fully cool down, if it be with a heat gun or running it in a parking lot. I dont change out my conrods or replace much of anything during my engines lifespan...I like to spend most of my time enjoying racing...not chasing tunes or replacing engine parts. jmho
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Old 07-01-2008, 11:51 PM   #29
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yea, everybody has their own methods (as some have excellent luck with the idle on the box method or break in stands)...i think the biggest factor while breaking in any engine is getting the piston & sleeve to expand at operating temps and allow it to fully cool down, if it be with a heat gun or running it in a parking lot. I dont change out my conrods or replace much of anything during my engines lifespan...I like to spend most of my time enjoying racing...not chasing tunes or replacing engine parts. jmho
Very true.

It's definitely a job that we all hate having to do though!!!
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Old 07-02-2008, 04:33 PM   #30
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LOL werd...
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