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d.h.
04-21-2008, 22:32
Went for my first long run over Cocahalla(not sure on spell). Summit is 1300 metres(4200ft).I was pulling empty horse trailer 1500-2000lb.One spot on climb is about 9% for abot 3miles.I found pyro temps rose very quickly were I had to back off or risk to much heat(above900).40mph was all I could get.This engine only has 900+/- miles so I know it will improve as I did,nt want to push to hard.

My question is all my mods from old engine went on this one.High pop inj were bench tested and all were still good.My old boost fooler was also used.I,m waiting on reprogramed pcm as fellow that insalled engine said it should make an improvement.
My old engine 23:1 would have climbed that hill at close to 60mph with that small a load(give or take a little)
Will this improve that much with new pcm? I don,t expect that much above old engine but, if I hook on my 34ft fifth wheel(12000lb) this summer I fear I,ll have a heck of a time pulling with those kind of pyro #,s.

These 18:1 engines are supposed to give a little better sustained cylinder heat control,are they not?
I noticed on return trip with 1 horse in trailer when torque was locked if I held boost at12-14lb on a hill pyro heat stabalysed below 900 and held.As soon as downshift occured and rpm went up pyro immediately went up until i could get boost back up again.

Maybye its a bit of a learning curve with 18:1 as apposed to 23:1.
Sorry for rambling but I know you guys have dealt with this kind of stuff :)
Thanks Dave

More Power
04-22-2008, 00:43
Just changing the CR shouldn't produce a noticeable difference in perceived or measured power. It takes a change in fuel calibration and/or boost pressure to produce a change in performance.

I suspect something else changed after the engine swap (i.e. turbo operation, injection timing, etc.).

Jim

DennisG01
04-22-2008, 05:07
Yes, I'd have to agree. I have not towed with my 18:1, yet, but I certainly expect to see an improvement in EGT's under load. My engine was built by Ron Schoolcraft - have you seen the articles in the member's area about this? There is a 3-part article. I think he is also featured in the latest (or maybe the 2nd last) pull-off. Ron was able to do some pretty amazing things with a 6.5.

If you can't find the 3-part article, do a search for any thread/post by "RonnieJoe" and the link is in his signature.

EDIT: The reason I mention the article and the pull-off is that you'll see a lot of good info on what an 18:1 is about and what it can do. Maybe you can use some of that info as a comparison.

Robyn
04-22-2008, 07:07
Review your setup as it is now as compared to what it was.

The power level as has been mentioned should not have changed all that much.

Make sure your timing and such are just as before.
Does the truck have an improved chip in the PCM now?

Interesting that the drop in gears should see the heat go up. My dually will usually cool off considerably when the RPM's go up.

As soon as the RPMs drop down on a hard pull the boost will rise up and stabilize and the heat will follow quickly up to about 900F (Post turbo)

To see such a change means other things have had to have changed too.

Now there does exist the possibility that your particular setup does not have the sweet spot where the old HIGH COMP engine did.

A chip that is set to allow optimal timing, fuel delivery and boost for the 18:1 engine will probably solve all these issues plus give overall better performance.

The proper chip will eliminate the need for the boost fooler.

My Dually has the Turbo master and the chip is the latest incarnation for the setup. Now I am still running the stock Compression so this will make some difference.

Go over the setup and make sure things are all as they were except for the comp.

Best

Robyn

TAG
04-22-2008, 17:04
In july 2006 i bought an 8x24 finished enclosed trailer, loaded it up with quads & gear, hauled it from my shop on a friday night to a campground 80 miles north at 90 deg , fought the temp thing all the way. A/C on, off, downshift, upshift, slow down, tried everything, it was a very trying trip & i was p--sed. A month later i started getting bubbles in the cooling system so I installed a penn 18:1, same mods as before plus intercooler & late model cooling mods. Left my shop again on a friday night with same load at exact same ambient temp, drove exact same route. Engine had about 150 miles on it. Set cruise at 70, never turned off a/c, never went over 900 on egt, coolant temp never went over 200, was a very pleasant trip. My guess is your not getting enough air. turbo master seems to eliminate many variables.

d.h.
04-22-2008, 19:47
Thanks for replies. The new engine is a Peninsular 18:1. I ,m a little suspicous of timing as well. Engine rattles a little louder than before on cold start.Is this related to timing? I thought it was.
Engine is appointed with same add ons as old engine.Same i/p ,i/c and high pop injectors.Air flow is also good with good high flow filter.
I,ve read articles on both Ron,s engine and Jims 6.5 project truck.This is why I went in this direction.
I,m after the lower egt,s while towing.The new pcm from heath I,m hoping it will bring things into check as you were mentioning:) I, m not sure why egt,s climb with higher rpm.? Old engine did this as well.The engine definatly cooled off a bit with higher boost.
As Robyn said old engine had a definate "sweet spot" that I could hold for a long time.I,m hoping I can find one on this engine too:)
I,ll hook onto fifth wheel when I get new pcm installed and try again.Not to many long grades on Island but I should be able to find somthing to warm it up.

ronniejoe
04-22-2008, 21:00
I'm assuming that you are still using the factory turbocharger.

With the stock turbo, egt rises at high rpm (for instance, pulling a grade, downshift from OD into 3rd) because the turbine housing is too small to flow the air that the engine wants to flow. Based on my experiementation, I believe the flow is actually choked at the throat entrance to the turbine wheel. In fact, the pressure ratio follows a constant speed line which is consistent with choked flow on the turbine side.

My turbo, as described in Jim's recent article, fixes that problem.

d.h.
04-22-2008, 21:12
That makes sense Ron I,ll do a little more reading.I thought this would be a next step once I established the paramaters of new engine.(with new pcm)

ronniejoe
04-23-2008, 06:20
FWIW, when I ran Heath programming on my truck with stock turbo, it tended to increase egt over Kennedy programming.