VT Engine Break In

[04YELLOWGT]

As you heard I ordered a VT Sportsman Short Block, and I was wondering how everyone that has installed a new short block or rotating assembly broke in their engine? Some say after about 500 miles its ok to “beat” on it others say to follow VT’s directions on break in. I’m not sure what to do and was curious as what other people have done. Also when would it be safe to get it on the dyno? The reason I ask is because along with that I’m having 31 Spine Axles with Eaton Posi, GI Joe 8 Rib Kit with 2.8 pulley and Cobra Tank with Pumps installed. Obviously the only thing that needs to be tuned is the 2.8 pulley. but will it be safe to drive the car for xxxx amount of miles with no tune as long as I stay out of boost? I’m having it tuned at Brenspeed so maybe that can just give me like a base tune for now until I can get it on the dyno.

I want to have everything ready once the short block comes in and I’m trying to figure out what I need to do. If I do need to follow VT’s break in procedure I figured Ill drive the piss out of it for about a week, so I can get the 1,000 miles on it. lol

 

[austin_hubbell]

well engine break in should be 1000 miles of easy to moderate driving trying not to stay at one solid rpm for extended periods.... ie don't drive to a 1000 mile away destination at 65mph the whole time . change the the oil at what you feel comfortable i did 200 500 and 1000 and then every 3000 miles but its your call. after that you can get on it some but i would wait till 2000 miles to start dyno and beating the **** out of it.

As far as tuning the base tune should get it started then just have them do a tune with just cruising and idle no full throttle on the dyno brake in the motor then have them finish the tuning after it is broken in.

 

[GodAmGT00]

Personally, I've always went by the method: If you're planning on boosting the engine, boost it a couple times, since it helps seat the rings..

However, on their site, VT outlines their best recommended method for breaking in their engines.. I wouldn't stray too far from that..

In fact, you should call them, and find out what else they recommend.. If I paid that much for a shortblock, I wouldn't f- around at all..


JT

 

[jivepepper]

Run the piss out it.

 

[04YELLOWGT]

Is that what you did jive?

Ive seen sites where they say that the rings set in the first 20 miles and that you should do short burts to set the rings. They also say by not doing that, the rings dont set right. Im so confused on what to do.

 

[ADRENLN]

im in the exact same boat as you. trying to figure this out for the summer. i will be doing pretty much the same mods and doing them the same way. putting the whole thing together with the blower, then tuning after engine break in.

however, the more i think about ti, the better it seems to leave the blower off till the engine breaks in. it is going to be a pain in the ass to stay low in the rpm band and stay off the throttle for that many miles.

also i think for engine break in, as previously stated, it is good to vary engine speeds, and rpm levels while putting on the initial miles. with the blower on and on tune, it is going to be hard to do this.

 

[Saleen4971]

if they ahve a recommended break in for their motor, do it.

you dont want to have a problem, adn them not warranty anything for soem stupid break in procedure

 

[superstang01]

if they ahve a recommended break in for their motor, do it.

you dont want to have a problem, adn them not warranty anything for soem stupid break in procedure

i agree with you ,I would follow the break in procedure that they recommend ,then if something goes wrong they will give you the warranty.

 

[04YELLOWGT]

The things is though how do they know if I broke it in right or not? I guess I also think about new cars. I know guys with Shelbys that were at the track before they turned 100 miles. So whats the difference?

 

[04YELLOWGT]

I know more people have built blocks. What did everybody else do??

 

[jivepepper]

Is that what you did jive?

Ive seen sites where they say that the rings set in the first 20 miles and that you should do short burts to set the rings. They also say by not doing that, the rings dont set right. Im so confused on what to do.

I didn't beat it but I did put some decent loads on it. First I was doing 3rd pedal runs from 2.5k-4k then letting off the gas and letting it coast back down. Then about half a pedel runs from 2.5k 4500 rpm and letting off. Then finally from a little more than half pedal runs from 2.5k to about 5k and letting off. This all in fourth gear within 20 miles. But this was after I let it fast idle for few minutes then checked everything out first. I might have pushed it a little harder if I wouldn't have had the SC on there.

I went home changed the oil and drove normally but staying out of boost for 500 miles changed the oil again and went to the dyno. 6k miles later it still runs really smooth and no smoke.

im in the exact same boat as you. trying to figure this out for the summer. i will be doing pretty much the same mods and doing them the same way. putting the whole thing together with the blower, then tuning after engine break in.

however, the more i think about ti, the better it seems to leave the blower off till the engine breaks in. it is going to be a pain in the ass to stay low in the rpm band and stay off the throttle for that many miles.

also i think for engine break in, as previously stated, it is good to vary engine speeds, and rpm levels while putting on the initial miles. with the blower on and on tune, it is going to be hard to do this.

You really have to hold the pedal to the floor to build boost. Even at 3/4 of a pedal you will see very little if any at all. Besides I still had my previous tune and I now had lower compression, an intercooler and a little less boost. So I was actually a little safer probably.

 

[LaserRed01GT]

I would absolutely follow VT's break in instructions. I read them on their site and they are fairly straightforward and common instructions.

http://www.vtengines.com/low_technical.htm

You definitely want to break in the motor with the blower and applying moderate boost. The boost will significantly increase the effective cylinder pressures and will change the way the ring enagages the cylinder wall and how much the ring is pushed out by the gas ports on the pistons, specifically on the thrust side of the cylinder wall. Yoo don't want to break in the motor without the blower, then put the blower on after the break in. You will have excessive boost blowby and you will likely use some oil.

Make sure, like VT says, that you DO NOT use synthetic motor oil for at least the first 1000 miles. Some builders will say after 500 miles. I do not know the specifics of the VT shortblock, so I would just follow the VT instructions as to satisfy their warranty if so needed. Synthetic is so "slippery" that it will not allow the rings to properly seat.

The key thing is that you want to place brief bursts of load on the motor to properly seat the rings. Don't beat on it or go WOT, just apply load throughout the low and mid RPM range. You want to vary the RPM more often than not.

 

[Matt's 03 GT]

You definitely want to break in the motor with the blower and applying moderate boost. The boost will significantly increase the effective cylinder pressures and will change the way the ring enagages the cylinder wall and how much the ring is pushed out by the gas ports on the pistons, specifically on the thrust side of the cylinder wall. Yoo don't want to break in the motor without the blower, then put the blower on after the break in. You will have excessive boost blowby and you will likely use some oil.

This brings up a question for me... What hapens on a factory motor run for say 50,000 miles before a blower is put on it. It seems by using your logic that there will be excessive blow by because the rings wouldn't have been set while using the blower???

I am sure you have much more experience with this than me so please help me understand. I am always up to learn some more! :SNSign:

 

[ADRENLN]

got it. i will also ask vt about the break in with the blower when the time comes, but i think this thread gives you a fairly good idea what to do. just follow vt directions, vary the rpms and load.

 

[mogs01gt]

If you bought a VT engine, follow VT's instructions.

 

[04YELLOWGT]

do you have a blower on your car?

How should apply load with a 2.8 pulley? My tune is for a 3.25 so this is a big change.

 

[saleen556]

I would absolutely follow VT's break in instructions. I read them on their site and they are fairly straightforward and common instructions.

http://www.vtengines.com/low_technical.htm

You definitely want to break in the motor with the blower and applying moderate boost. The boost will significantly increase the effective cylinder pressures and will change the way the ring enagages the cylinder wall and how much the ring is pushed out by the gas ports on the pistons, specifically on the thrust side of the cylinder wall. Yoo don't want to break in the motor without the blower, then put the blower on after the break in. You will have excessive boost blowby and you will likely use some oil.

Make sure, like VT says, that you DO NOT use synthetic motor oil for at least the first 1000 miles. Some builders will say after 500 miles. I do not know the specifics of the VT shortblock, so I would just follow the VT instructions as to satisfy their warranty if so needed. Synthetic is so "slippery" that it will not allow the rings to properly seat.

The key thing is that you want to place brief bursts of load on the motor to properly seat the rings. Don't beat on it or go WOT, just apply load throughout the low and mid RPM range. You want to vary the RPM more often than not.

I am not understanding this advise. If this were the case everyone with a stock GT that adds a blower would have blowby issues.I am following VTs breakin procedure and have my blower locked in valet mode so I don't get ANY boost.Since I need to break it in before I hit the dyno it seems pretty foolish to get into any boost at all without a tune.I broke my stock motor in the same way and didn't have any issues at all even after installing the KB.

 

[Fast Eddie 41]

My name is Matt, I work with Kevin (laserred01gt). What he was trying to say was that you should always break in a motor under normal operating condtions....if you have a n/a motor...break it in n/a. If you have a blown motor....you break it in under mild to moderate boost...that's just the way it's done.

Kev probably can better explain this than I can....and I'm sure he will add his two cents ...but you have peaks in the cross hatch from the final hone. These peaks must be leveled just right by the ring so that you have proper ring seal. Rings are actually pushed out after ignition from the pressure of the combustion....obviously the resultant outward force placed on the rings will be greater under the stronger combustion of a blown motor. You don't want to go into boost until after 10 mins after the intial fire up. And I'm sure that this guy told VT Engines that this shortblock was going to see boost. That changes the type of ring set, the end ring gap, and the way the tension placed on the oil rings. We prefer to use the Speed Pro Hellfire rings with the reverse twist second ring. Research has shown that 60-70% of the heat dissipated from the piston leaves through the rings. It's very important to pick the proper ring, end ring gap, and break them in properly on a blown or motor.

If this isn't done, the rings will seat themselves as if the motor were going to be n/a....then as soon as you apply boost you are going to cause abnormal ring deflection, specifically the compression ring and oil rings. This will create additional heat in the piston, allow a greater chance for boost blowby, and allow for oil blowby in to the combustion chamber on decel when the throttle is immediately closed. Some people might not notice that there is boost blowby because most people don't know any better or don't a way of measuring crankcase absolute pressure....but if there is you can rest assured that there will be a much higher crankcase pressure if not evacuated properly or a difference in outlet compressor PSI versus the PSI you should see at the manifold.

Kevin will chime in later I'm sure.

Matt

 

[ADRENLN]

can you please explain to me then how you do this with a blower on a built engine? how can you be applying boost when you dont even have the car dyno tuned yet, you not supposed to be in boost on an untuned car. that is not good for the motor! and you cant dyno tune the car until the engine is broken in, so how do you do this?????

 

[tomustang]

Make sure, like VT says, that you DO NOT use synthetic motor oil for at least the first 1000 miles. Some builders will say after 500 miles.

That's what they told me