6.2 or 6.5 injectors, rush answer needed.

[coxfmly]

Hello, I would like to ask aquestion about injectors. My truck is in the shop and I have been told that 5 injectors are bad. The truck was running very rough like it had a "3/4 race cam".
My mechanic said he can replace the 6.2 injectors, I mentioned the upgrade to 6.5 units.
He said it might help a little with performance since the inlet pressure is greater. My I.P. is a year old and seems to be fine.
What should I do and why? I dont like to push but I need to give him a answer tomorrow.
I have looked at the archive and have found varied answers.

Peplace 5 6.2 or install 8 new 6.5...
Please help, Thanks

[john8662]

6.5 turbo injectors since you're turbocharged! Replace all 8 as a set, the mechanic will have to tweak the lines to get them to match the short body 6.5TD injectors, just slightly, I haven't had a problem with this.

Is this the first time the injectors have been messed with?

[coxfmly]

Thanks for the fast response.
I had 2 injectors replaced last year along with the I.P. I was going to replace all 8 but I was unsure which way to go.
Are the new 6.5's better from a upgrade point of view or ? I really dont know all of the pro's and con's but I do value the information received by the DP members.

I will let you know what the cost per item is. I'm not looking forward to it.

Thanks for the information, Paul

[john8662]

Paul,

The 6.5 injectors will be more pricey, mainly because that's what is in demand. The 6.5 has a higher pop off pressure than the 6.2 injectors did. Mainly this means that if your IP can handle them (probably will with no problems) that the fuel will be atomized better, but using the same amount of fuel. You'll get a better burn and possibly a little more power.

I think either way you'll find this is a power increase over having 5 bad injectors. By the way, what was wrong with the 4 deemed bad, did they fail the pop test or leakdown test or have a bad spray pattern, or all the mentioned?

[coxfmly]

Update, They fail the pop test, leakdown test and had bad spray pattern. I had the 6.5 injectors (8)installed and I have noticed a few things.

The truck feels a little stronger and the boost guage really jumps. Prior to the fix the boost would come on in a very steady fashion. Not very quick but steady. Now the boost jumps up the scale. I notice that the boost comes on hard at any speed. When rolling down the street I can hit the gas and the truck reacts in a much quicker time. It doesn't seem to have as much lag.

One other thing I noticed is the EGT climbs just as fast. I can't recall the temp reacting in such a manner. The temp will climb to 900+ when pushed hard. I had it on the freeway and it would stay in the 500 to 600 range while cruising. I have to say I didn't have much time to check the temp due to traffic.

Should the boost climb so fast?
The truck's IP is a year old along with the Banks turbo set up.

Thanks for all of your help, paul

[britannic]

This is all good! Enjoy the power, 900F EGT is fine and safe - keep a close eye on it if you're towing though. What boost levels are you seeing?


Originally posted by coxfmly:
I had the 6.5 injectors (8)installed and I have noticed a few things.

The truck feels a little stronger and the boost guage really jumps. Prior to the fix the boost would come on in a very steady fashion. Not very quick but steady. Now the boost jumps up the scale. I notice that the boost comes on hard at any speed. When rolling down the street I can hit the gas and the truck reacts in a much quicker time. It doesn't seem to have as much lag.

One other thing I noticed is the EGT climbs just as fast. I can't recall the temp reacting in such a manner. The temp will climb to 900+ when pushed hard. I had it on the freeway and it would stay in the 500 to 600 range while cruising. I have to say I didn't have much time to check the temp due to traffic.

Should the boost climb so fast?
The truck's IP is a year old along with the Banks turbo set up.

Thanks for all of your help, paul

[coxfmly]

Hello, The boost seems to jump up to the 7-8 range when leaned on. I hadn't noticed the boost climbing so quickly and so high without a trailer in tow.

In the past I could get on it and the boost would barely climb. It would climb but not so high without a load. It now seems to respond in an all around better way.

The boost has never gone above 9 and I keep the EGT below 1050 if I'm going up a steep grade with the trailer.

I really need ot jump up to a Gear Vendor unit but the cost is too high at this time.

It's seems strange to invest big money to keep these old trucks going when the market can only support a 3-4000 sell. I've invested 4K over the price of the truck and will never see the return.

I can only hope to keep it on the road for another 200k.

Thanks Paul

[NH2112]

Originally posted by coxfmly:

It's seems strange to invest big money to keep these old trucks going when the market can only support a 3-4000 sell. I've invested 4K over the price of the truck and will never see the return.Not as strange as investing BIG money in a new truck, just for the privilege of either having all those problems and taking it in the shorts when GM won't pay or having to baby it for 4 years so you can make enough on selling it to pay off what you owe on it and also have a downpayment for the next truck. Like the old ad said "Resale value? Buddy, I'm gonna drive this truck into the ground."

[Dezman125]

Hi
You are looking at owning a classic in the wrong way.
Not everyone can own a classic GM product.
Not everyone can keep a classic on the road as a dayly driver.
If you keep your truck in good condition there will come a time that it will apreciate in value.
Nowadays almost anyone can sign their name to making payments on a new truck,with warrenty for a number of years,so they don't have to know anything about the truck,except that you have to put money into it on a monthly bases,turn the key to start,and fill it with fuel.
Even the new trucks tell you to service them now.
I will happily keep driving a working on my old GM products,chances are that if something minor happens on the road,i will be able to limp home,which up here with 100's of miles between towns is peace of mind.New vehicals ar not so forgiving.
My parents have a 03 Jetta TDI.I changed the winter tires on it,drove it out of the shop and parked it.It would not start and run when my dad came to pick it up.Nearest dealer 1600 miles,warenty covers the tow,but how long till they get a car back?
Till the day i can't hold a wrench i will be driving my classics,then hopefully they will be a good GM and keep running :rolleyes:

[coxfmly]

Hello, Well now that you put it that way....
I guess I never though about the other side.
I do have a very clean truck that keeps ticking.
Yep, I do have issues once in a while but for the most part it never lets me down.

As far as keeping these old trucks going, I have a 53 F-100 Ford that I've had for over 20 yrs.
Its been tranformed many time from the factory 6 cyl, 302 Small block and now it has a 454 for that get up and go. It has been around the family
for over 35 yrs.

When I think of limping home, My wife and I had driven the 53' coast to coast and all around. While in Alabama an elderly man offered my wife a goat and a gallon of BBQ sauce for it :)

I do wish I could find a Suburban/diesel club in southern California to hang with.
I have a friend at work who has a 1/2T 4X4 sub that he takes out but thats off road and I only have a 2wd.

I only know of 1 Diesel shop other than the factory. It does get tough when I need it worked on. Fortunately my mechanic is only a few miles away. I am able to do all tasked subject to the engine. I am learning more but I need to get a hold of a good set of factory repair manuals.

Well, Thanks for the view from the other side of the street.

Paul

[Stray Cat]

FYI...no difference in power between 6.2L and 6.5L-turbo injectors. We tested on a dyno (see "6.2L-TD experiment") and there is no difference. The pop-off pressure is higher with 6.5L-T injectors. That may add efficiency, but not power. I'd bet the added power is from turning up the fuel delivery on the IP.