Which Pistons, upgrade cam?

R

Redrider2911

New member
So I blew the head gasket in my truck the other week. I'm going to tear the whole thing down and rebuild as the block hasn't ever been resurfaced which I believe caused the issue, and I've had horrible blowby most likely from cylinders being out of round. I'm wondering what you guys might suggest for a daily driven weekend play truck in the 650-750hp range? I love the low end torque of this truck which is why I built my compounds to come on so early. I easily make 10psi by 1100rpm and 20psi by 1250, I can be at full tilt 85psi by low 2000s. I do tend to have low end part throttle smoke and higher egts than I would like. 850* cruising at 70mph with 15psi of boost. Part throttle take off is 1050-1100* easy... Any grade can bring my truck to 25psi and almost 1200*.

What do you suggest to improve upon my current setup?

Daily driven/weekend raced
Mild head porting
23* timing
quick spooling compounds
medium/low budget

Thanks for any help,
Kris
 
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I'm very surprised by your egt's mine are 650 to 700 cruising 800 to 900 accelerating rarely over 1100 under heavy throttle as long as I let the turbos spool before laying into it. Whats the deal with your intercooler. Is there any way you could upgrade to a larger unit with a bigger heat exchanger?
 
Well I think I have a couple things going on. I believe that this engine might be quite a bit weaker than I am guessing. I mean it has over 300k miles on it, I did a rering a while back with some honing with a 3 stone hone; but it didn't help with my blowby at all. I have a feeling that these cylinders a way out of round and I am actually losing a decent amount of cylinder pressure. Im hoping Im right and that alone will help streetability.

I did some testing and temp readings with my intercooler setup pretty much when I first put the system together and I was super happy with it. I have a habit of putting my hand on the intercooler whenever I get out of the truck to get a feel for temps. I will say that this last year the is seems to feel quite a bit warmer than before and I think a couple things are attributing to that. Cant run coolant at the track and I didn't run enough Hyperlube in the system towards the end of last year. I know that I have a lot of rust stuck to the aluminum heat exchanger and intercooler and I need to use something to flush out the system real good. Additionally, I had a run in with a snow bank last winter and the fins toward the bottom half of my heat exchanger got mangled and pushed closed which I know isn't helping keeping things cool. Maybe those few things on my maintenance list are adding up to higher EGTs... For sure possible.
 
Based on your intended use I would use the MAHLE 224-3525WR

It will give you the big bowl design which allows more timing while still spraying in the bowl.
They maintain higher compression than a marine piston. Which will help with the bottom end power and faster spool up.

Reach out to Jeff (Snedge) for pricing. Also, pick his brain, he may suggest something else. But, I believe he will suggest that piston or an equivalent through McBee.
 
I'm planning on using the non intercooled pistons as well. Great bang for the buck and the compression is very close to the stock pistons. I'm planning on refreshing the my motor over the winter as well. Mine was mostly due to a head gasket issue and a busted front timing cover. My motor never had any real blowby, but the motor is older and the connecting rod bearing are showing signs of wear. I might as well fix all the leaks and upgrade to arp mains and connecting rod bolts while its out.

It sounds like you are on the right track with all the little changes you have seen. I work in refrigeration and all those pieces as far as your intercooler could very well be causing a significant drop in overall efficiency.
 
Make sure the blocks deck surface is flat as well as the head, with that much boost it'll need o-ringed.
I'm running Mahle 1st gen non inner cooled pistons in my tow rig in order to run the 155 degree spray injectors.
Unless you plan to operate at higher rpm's stick with a stock cam (wish I had).
 
Yea. Head had been surfaced. Block had not. I had orings in the block.

I thought the whole point of running the wider bowl was to run the narrow spray pattern and then still end up in the bowl at a higher timing advance?...
 
Destroked 450 said:
Unless you plan to operate at higher rpm's stick with a stock cam (wish I had).
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I’m curious what cam you are running in your engine. You’re saying stick with a stock 12v cam? From which year?

My impression was a cam shaft upgrade in a diesel is worth while. (178/208 style for towing upgrade)
 
To over simplify, cams move torque curves.

I've been impressed with 188/200 trucks that I've ridden in. But they are had torque curves that were really useful until 2000+rpm

Sent from my XT1575 using Tapatalk
 
Red Sleeper said:
I’m curious what cam you are running in your engine. You’re saying stick with a stock 12v cam? From which year?

My impression was a cam shaft upgrade in a diesel is worth while. (178/208 style for towing upgrade)
Click to expand...

I was going to install a cam in my tow rig similar to the specs you listed, but they were out of them at that time, I let them talk me into the next size bigger (181/210) which I now feel was a mistake, this cam pulls strong above 1800 rpm but is a bit doggy down low when pulling away with a load or upshifts that pull rpm's down into the 15-1600 rpm range or less.
The cost benefit from a cam change should be ether increased performance or increased mpg, I gained neither because the cams operating range is not where I need it.
Installing a aftermarket cam instead of stock adds around $4-500 to the cost, if your replacing a good stock cam that's $1000 cost.
For the average daily driver/tow rig it'll take tens of thousand of miles to justify the cost.

If it's a performance build where you'll be operating at higher rpm then yes you'll benefit from a bigger cam.

Thus my original statement, unless you plan to operate at higher rpm stick with the stock cam, spend the extra $$ elsewhere.
 
Thanks for the explanation. I remember first learning about Hamilton Cams when they had the 188/210(?) cam and maybe they still do. Read articles of a cam swapped early common rail and the return on investment was around 60,000 miles at the time.
I have not ridden in a truck with the 178/208 cam, though I tend to favor that cam personally for my type of engine work/performance. (Towing mainly) I tend to keep things for a long time.

Back to the topic at hand.
 
This is all good info. I actually appreciate all the responses. So what about the comment Jasonc made about injector angle? Even on stock pistons?
 
biggy238 said:
You mean running a mismatched spray angle?

Sent from my XT1575 using Tapatalk
Click to expand...

Correct. Why would you want to run the wider pattern? I thought the whole point was to run the wide bowl piston with the narrow spray pattern to keep the fuel in the bowl at higher timing....
 
I've always heard you didn't want to spray outside the bowl but that's not why I went with wide bowl pistons.
I read some articles about the reason for the smaller bowls, they said the smaller bowls were for emissions not allowing a complete burning of the fuel, is caused a lower combustion temp lowering the NOX emissions.
My theory was with wider bowls I could get a more complete burn and hotter combustion which should in effect make a slight increase in power on the same amount of fuel injected.
This is just my theory and I have no scientific proof of any actual increase in power using wide bowl pistons with a wide spray angle, it just seems to make since that with more air under the spray the better and more complete the burn should be.
I don't run high timing on my tow rig, 15-16 at best.

I could be wrong, have been before, will be again.
 
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Redrider2911 said:
This is all good info. I actually appreciate all the responses. So what about the comment Jasonc made about injector angle? Even on stock pistons?
Click to expand...

In my experience wider spray pattern injs have made more power and drove the charger harder than the same size 145's.
 
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