Halfton 12 valve mods.

JQmile said:
My 89 gets about 27mpg highway (slow) 24mpg (fast) and 20mpg in the city. I run 27deg of timing though, I'm light, low, and 2wd. Also 3.07 gears with the OD trans. I am sure my 5x25s aren't helping out any, with DDP injectors I hope to break 30mpg. Aero is huge, so is speed, and so is timing. Those are the main big helps I have found. Use your EGT as a fuel economy gauge, the lower the egt, the better the mpg should be. I know Crabbelle got 30+mpg on his light 2wd with a cam, double OD, etc. Can't find the thread, otherwise I would post it.

I might be showing my nerd side here, but you can always check out Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com for ideas.
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You got me thinking about the EGT gauge. Funny at 70 truck runs 700 degrees yet at 60 it runs 600. 600 is just about the lowest it goes driving. Seems a bit hot to me.
 
I'll sell ya my 7x.014 just back from being freshened up and you can find out.

Sent from the recliner butt naked
 
I'm sure I am well aware of the effects of altering the injector installed height, but you are 8° from "correcting" the cone angle.

It's almost comical that immediately after telling you they suck, you offer to buy them.
 
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Back on topic.....if I remember that has industrial style piston and I'm still thinking timing. Timing was at 20 and you lowered it, but what happens if you advance pump timing. I don't know what stock is on the industrial application but marine is 20° I believe. I'm sure someone who knows will chime in.
 
Which piston are you calling the Industrial? Factory timing on the Marine engines varied a bit between 24-30° in factory form.
 
bulldog77 said:
Honestly, id ask to much and wouldn't feel comfortable selling them. Probably just have the nozzles switched to a 5 hole here in a few weeks.

Sent from the recliner butt naked
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Seriously, PM me with a price because i'm interested in these nozzles... they can't really be worse than the 370s i have now... or can they ?
 
CPSimpson said:
Back on topic.....if I remember that has industrial style piston and I'm still thinking timing. Timing was at 20 and you lowered it, but what happens if you advance pump timing. I don't know what stock is on the industrial application but marine is 20° I believe. I'm sure someone who knows will chime in.
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On off topic meeeehhhh i like reading westons posts. I would play with timing but it is just out of the question unless some new motor mounts are made. It shook so bad at 20 that my teeth rattled and the truck was litterally backing off bolts daily. I adjusted timing say 5 times and settled where it is now. It still shakes but not near as much.

angelic0- said:
Seriously, PM me with a price because i'm interested in these nozzles... they can't really be worse than the 370s i have now... or can they ?
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Everyone that knows allready told you they suck. I would suggest you buy them and try them out.
 
Smokem said:
Which piston are you calling the Industrial? Factory timing on the Marine engines varied a bit between 24-30° in factory form.
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I'm not familiar with all the details of the engine build but I think Darren would know. I just remember something being said about an industrial piston design. With that being said what are your thoughts on timing being set that low.
 
Mileage can be quite good with timing in that range, just depends on how everything is setup, I imagine going to a larger turbine would bring it down from what it was previously.
 
My 300k mike 12v with 5x.014's, 131's, and 15.5* got 20-21 when driven right. 5 speed truck.
 
Truck had a 180 degree thermostat. I added the napa 195 degree super stat a few minutes ago. The 180 would get to a peak temp of 195. The 195 gets to a peak temp of 200. Guess the wax filiment was off on the 180. Glad i didnt waste money on some high temp coolant.
 
VMAX said:
You got me thinking about the EGT gauge. Funny at 70 truck runs 700 degrees yet at 60 it runs 600. 600 is just about the lowest it goes driving. Seems a bit hot to me.
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There's a couple schools of thought on it. One is to basically run N/A with enough timing to get down the road and make some power, this is basically the theory my 89 is using. Makes 0psi on the freeway, and runs anywhere between 400 (slight downgrade) to 600 (slight uphill) on the freeway. About 65mph.

The other way to approach it is to try and use the turbo to make some power and boost at cruising. I think if you went to like a 57mm/75mm setup you'd probably see a few mpg increase. My 95 Dodge went from 15.5mpg with a 71mm to 18.5mpg with 57/71mm compounds.

Not sure which way is better yet, I'm kind of curious what my 89 would do with twins.
 
Parked the truck for a while. Got the flu and it was much more pleasant to drive the 6.4 when i had to drive. Just filled up from the synthetic 2 cycle and 195 thermostat and got 23 mpg. Next is westons injectors. I think we will see a good jump.....
 
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