Matts440
Well-Known Member
Bummer he's that busy but can still have a little fun while you wait lol true can just have it all done at the same time.
Another small block turbo early valiant
- Thread starter V8-valiant
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TT5.9mag
Two atmospheres are better than one
How are you logging boost pressure? I would verify that whatever sensor is measuring 23.5 psi is accurate for starters. Matts440 is correct, you need to give more priority to exhaust flow through the wastegate and even that might not be enough. You may also need a larger gate. And at that boost pressure I would look at the headgaskets first hopefully your problem is there and not crack in a cylinder or head. Good luck. Keep us updated.
I have a Fitech EFI system on it, that’s how I’m logging all the data. I spent some time on the turboforum.com and the guys over there helped out quite a bit. Apparently there are two points you can hook up the boost reference on the bottom of the gate, I needed to plug the one I wasn’t going to use. (Rookie mistake). I believe this should take care of my overboosting issue. Now onto the water issue. I was told that there were a few things working against me in a negative way and that it was possible I lifted the head, that’s how water got into the cylinder/oil/catch can. It would be common,lifting a head,on a new un-tuned combo that was getting into high boost while over temp,all negatives. So, at this point I’m going to put some fresh oil, fresh plugs in it and go log some miles and see how it goes.
I agree the wastegate mounting isnt ideal, studying my photos it doesn’t look as BAD as I thought. I do think it would benefit if it was placed where the red line is in the picture. (Please I know my editing skills are on point).
dusted
Well-Known Member
I had a FITech PA on the truck and I believe it only had a 2.5 bar map sensor. So 21lbs would be it. Are you using an boost gauge to verify? Also what Head gaskets? I see the head studs.
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dusted
Well-Known Member
Waste gate looks fine to me.
Ahh yes, I didn’t think about maxing out the map sensor. I do not have another gauge to verify. I’m using cometic gaskets.
dusted
Well-Known Member
You may have slightly lifted the head, proceed with your plan and see how it does.
TT5.9mag
Two atmospheres are better than one
So with cometics and studs, if the deck and the heads were prepped correctly, I dont see you lifting the head or pushing out a gasket at 23 pounds. Maybe I’m wrong. I hope I am because it means the water came from a somewhere much worse.
Ok guys it’s been quite some time, I’ve been getting a little work done on the valiant. I pulled the passenger side head to find a bad head gasket and a couple pistons that didn’t like all the detonation. 
I put a different gasket on it and back together just enough to drive it on and off a trailer for our move out of state. We barely got all our boxes put away and started pulling the engine out. Had a couple plans to get it back together on a budget and beat on it without concern but they didn’t work out. At this point I’ve started a new engine build with a Molner stroker crank and custom pistons, finally got the pistons Friday so I can drop it all off at the machine shop for them to get going on the engine. I hope to have it back together to enjoy a little before the weather hits here.
I put a different gasket on it and back together just enough to drive it on and off a trailer for our move out of state. We barely got all our boxes put away and started pulling the engine out. Had a couple plans to get it back together on a budget and beat on it without concern but they didn’t work out. At this point I’ve started a new engine build with a Molner stroker crank and custom pistons, finally got the pistons Friday so I can drop it all off at the machine shop for them to get going on the engine. I hope to have it back together to enjoy a little before the weather hits here.
turbodart68
Well-Known Member
Ok guys it’s been quite some time, I’ve been getting a little work done on the valiant. I pulled the passenger side head to find a bad head gasket and a couple pistons that didn’t like all the detonation.
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WOW that got serious real quick. Here are the things i have learned along the way. Single turbo cars still need TWO waste gates. Think about it. Each bank gets a wastegate on a twin setup. Since you put a single turbo on it there are still two banks of exhaust moving air. You need to add another waste gate for the drivers side header. The closer to the collector the better because the exhaust is at its hottest and its more compact and a given hole with flow more air with more temp. Secondly, without knowing what boost and where you AFRs are you should never do a full pull. The burned up pistons are from prolonged full throttle under boost. This was an expensive lesson in comparison to a dyno session where you can control what goes on and for how long.
Agreed it was definitely an expensive learning lesson, there was many things working against me and my inexperience didn’t help. It did escalate quickly on the build lol. Well I realized the crank I was running was turned and 20 under and I didn’t want to run it, so with no luck finding a standard used crank I started looking at a new crank. It started with a scat 4” cast crank it was cheaper than the stock stroke! Only by like $10 lol. I was able to catch Racetec before they started making the pistons and was able to change the stroke. Then I got to thinking and decided to pull the trigger on a forged crank. I’m going to look into a second wastegate and placement. I’m also going to put a 3lbs spring in and just drive it a while before I make much boost so I can get the tune dialed and such. Also got a meth kit to put on and help with temps till I can find a place for an intercooler.
yellow rose
Overnight Sensation
Damn...you moved out of state??? I hate to hear that, except for the fact it was a good move for you and your family or you wouldn’t have done it.
I follow this thread because I love your car. Very cool.
YR
Sorry I may have worded it wrong. I meant to a different state. Washington to Oregon. Not out of the states. It’s been a really good move for the business and the family is really enjoying the new area too!
TT5.9mag
Two atmospheres are better than one
Ring gap, ring gap, ring gap. I can’t preach it enough for a turbo car. The damage you saw was likely caused by heat generated by detonation, and the rings butted, stuck to the bore and snapped a land. Open them up on the new engine or it will happen again.
Dartsun
Mopar Dude
Where about in Oregon you move to? I really like your valiant. Dustin
Thank you Dustin, I’m in Redmond Oregon now.
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Would you recommend using the piston manufacturer gap or a little more? Do you have a suggestion on how much gap?
TT5.9mag
Two atmospheres are better than one
On high hp boosted stuff I use .007 X bore diameter for the top ring on forged pistons. And I gap the second a little larger.
Here’s a good link
Everything You Need to Know About Ring Gap!
Here’s a good link
Everything You Need to Know About Ring Gap!
Thank you!
Dartsun
Mopar Dude
Nice deal Redmond is nice, my mom lives up central Oregon.
Houseoffubar
Well-Known Member
From what I have seen, on a blow through, an intercooler is not at all necessary on a mild boost system, or on one moving a ton of fuel (like E85) as it completely cools the boosted charge.
I am curious myself about whether twin or a big single wastegate is the best route, but the argument the gasses are smaller when hot does not make sense to me, air and many gasses expand when hot, so I would want more clarity there.
I am doing a single turbo, non-intercooled, blow through with the carb in a box, but as a mild daily driver (hoping for mid 12’s)
loving how clean your car is and all the work is top notch
I am curious myself about whether twin or a big single wastegate is the best route, but the argument the gasses are smaller when hot does not make sense to me, air and many gasses expand when hot, so I would want more clarity there.
I am doing a single turbo, non-intercooled, blow through with the carb in a box, but as a mild daily driver (hoping for mid 12’s)
loving how clean your car is and all the work is top notch
Thank you, unfortunately I bought this Fitech system probably 3 years before even starting the turbo build and by the time I got it together and wanted to try something else summit was going to charge me a restock fee so I figured I’d try it instead of loosing $500-$700 on this unit. We will see how it goes after I get it back together.
Yeah we are enjoying it! Let me know if your ever this way!
yellow rose
Overnight Sensation
Much better than anywhere on the west side...just like here in Washington. You are close to skiing, hiking, dirt bike riding...about anything you want to do outside.
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