My New, New 347

[4pointslow]

That bag would have had me chasing my tail all over the place with diagnostic tests that didn't help. LOL
I could totally see myself installing pipes and having this happen to me.
I hope the tuning goes much easier now!

 

[CDW6212R]

Ideal would be 18. I do get this when decelerating.
Yes, 10 is not great, but 4 was terrible.

Blow off is a pressure differential. So, when the throttle plate closes quickly, there's high pressure in the piping leading to the throttle plate, and low pressure in the intake manifold. The differential is what pops the valve open till the piping positive pressure goes down.

I'm sure it's the cam causing the vacuum issue. The turbo isn't creating boost at all at low rpm's. A turbo likes an engine under high load to start boosting. I don't have any vacuum leaks anymore, as I don't have that hunting idle on cold start up anymore. Famous last words , although finding another leak would be a cheap fix.

EGR was working, I confirmed it with those vacuum hoses reversed. The 10hg was holding the egr open just fine at idle, lol. The vacuum seems to be enough for the climate control.

Are the brakes super responsive and touchy with all that vacuum? errr.....no.
Are the brakes what I would consider dangerous now? no.
My options are not great for the brakes, its pretty much a cam swap or vacuum pump. I just want to get the thing tuned and drive it before I think about more expensive mods. The Volvo vacuum pump looks reasonably priced compared to other options, but then there's the finding a location for it, etc. I do reserve the right to change my mind though.

I hope the vacuum comes up a little after you get it all settled and tuned better. If not, how much would an electric vacuum pump cost, and have you considered a crank driven one, for the crankcase? I'd like to fit one in place of the bottom idler pulley, but I saw the prices for the good pumps at $400+, and stopped thinking about that.

 

[vroomzoomboom]

for what its worth john, don's cam is pretty close to what mine is, and thats pretty close to the same vacuum according to my gauge that I’m also getting

 

[Dono]

Don, its back to more complexity.
I'm not building a track vehicle, so a crank case evac pump isn't necessary. I have my pcv system working so the oil stays cleaner, and thats the main thing. Even if cost, and complexity were not an issue, I'd loose the pcv system, and I don't want to loose it (I actually like the design).

I think Tim should buy a brake vacuum pump. Then we can all see how he mounts it, and how it works. Cost is anywhere from $400 to $1000cdn. What do you think Tim?

 

[gmanpaint]

@Rick installed a brake vac pump on his crawler. I don't remember him saying it cost that much to do. I think he has a write up (or posts) on it. The 1st & 2nd gens are pretty much the same beast when it comes to the brake booster and vac.

 

[vroomzoomboom]

.

I think Tim should buy a brake vacuum pump. Then we can all see how he mounts it, and how it works. Cost is anywhere from $400 to $1000cdn. What do you think Tim?

after seeing the blunder i made on that innercooler.........PASS!

 

[Rick]

The pumps aren't cheap. I use mine as an emergency backup should the engine stall while climbing a steep hill.

I wouldn't recommend it on a daily driver as the pump can't keep up with stop and go driving. They claim they will work for that but it just doesn't feel normal at all

 

[Rick]

This is another option:
1930-1976 Chevrolet Truck Parts | PB10569 | Firewall Mount Electric High Power Master Cylinder | Classic Industries

 

[gmanpaint]

This is another option:
1930-1976 Chevrolet Truck Parts | PB10569 | Firewall Mount Electric High Power Master Cylinder | Classic Industries

That's a solution for sure, but Jeebus H on the price!

 

[Dono]

Sorry about the shipping Tim. I know your ultimately on the hook. I'm left feeling like a piece of **** wondering what I could have done differently.

On the vacuum thing, I might do something one day, If for nothing else the cool factor comes in to play. I't would be a cool mod to keep maximum street-ability.

Iv'e been adjusting my water/meth. For some reason (even with it set to start spraying at 3lbs, and max out at 19lbs) the truck bogs as soon as spraying starts (3 lbs boost). If I were to guess, the mixture isn't completely atomizing and hitting the maf sensor. I think I need to try a much smaller jet than whats recommended. I'd like to spray a bit of meth early (and with low boost) to maximize the benefits of the coolest inlet charge possible.

Boost comes on super quick and easy, probably the easiest it's ever come on. I still don't have the traction issues Tim seems to have, leaving a couple of black strips everywhere. As I tune, I might get there.

 

[vroomzoomboom]

you have your meth kit before your maf? isnt it suppose to be after it, but infront of your iat? or at least thats how i have mine. as for leaving j hooks everywhere on the pavement, you also have to remember turbo boost doesnt hit as hard as supercharger boost and the fact your truck is about 200lbs heavier then mine (i think). as for the shipping, we will hate on fed ex for that one.

 

[Dono]

My maf and iat sensors are the same unit. I wanted the iat sensor to 'see' the cooler air, but this is going to be a problem.

A few years ago I tried adding a separate iat sensor in the lower intake, but the truck saw super high temps at idle and started upping the idle, adding fuel, and pulling timing. Short story, ran like crap.
I guess I could re-install that sensor and shut this safety stuff off in the tune. Then I could spray after the maf and still 'see' the cooled air.

 

[4pointslow]

The cooling takes place more in the cylinder than the intake manifold.
When the atomized water evaporates from the heat of combustion, it removes heat in the combustion chamber.
I would just spray after the maf, that's where I have mine hooked up.

 

[4pointslow]

Not supposed to spray before 3,000 rpms either.

 

[vroomzoomboom]

Not supposed to spray before 3,000 rpms either.

Really? I have a aem controller and it’s controlled by boost reference. I have it set to come on at 3lbs of boost, and to go full on party mode at 6. I know if I just playing around town and blip the throttle it has come on before 3000 rpms

 

[4pointslow]

Copied from Snow Performance wather methanol kit instructions...
"Injecting water/methanol lower than 3300-3500 RPM could result in combustion quench"
and
"All vehicles are different. If the engine bogs or loses power, then injection is starting too early, the quantity is too much, or there is not enough methanol in the mixture (50/50 water/methanol recommended)"

 

[Dono]

I can see in the logs the weirdness that happens with the maf counts. I think I'm best to just move where I spray and be done with it.
Far easier than fighting with moving the iat sensor, etc.

 

[Dono]

I have an unhappy motor... Is anyone really, truly surprised? Some things just are not meant to be.

Iv'e been pre-fogging the neighborhoods in anticipation of mosquitoes. Blue exhaust.

So, the trouble shooting started.

#4 plug looks very oil fouled. Compression looks good.

Leak down....Looks great. With the valve cover off, I can hear hissing at the valve seals. Oil is obviously entering from the valve seals.
I'm going to need to replace all the valve seals with a different style of seals. I'm not exactly looking forward to it, its going to be a back breaking, slow going job in the truck.

 

[4pointslow]

How were the other cylinders, did those plugs look just as bad?
To replace the seals you usually put compressed air into the cylinders to hold the valve up while removing the keepers/retainers/valve springs etc.
Once you get the spring off, you could hold the valve stem up, pull the air out of the cylinder and then wiggle the valve stem to check for excessive valve guide clearance just to make sure there isn't anything going wrong there?

Of course if the seal is damaged from the spring hitting it or something, then maybe that's all that is wrong with it?
And at least the compression is good, that has to be a relief.
Hope you get it corrected without too much loss of sleep!

 

[gmanpaint]

Did the builders give you a break in period, and offer to work on it after, if anything happens...... Like this?