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Discussion Starter #1
Running.
Sold my 4BT five or six months ago; had a 4BTA to replace it.

Finished with my oil pan modification to fit D44.; as I lowered the suspenion from 3.5" back to standard coil springs. Pulled and shaped pan 4 times till I got it right. The pan touched the D44 this low; needed 1.5". Mod'd pan nearly 3": Made space over D44.

Fired it up today.

First observation. Cannot make this engine smoke (don't intend turn up the star wheel);) I like it.

Second observation: At 650 RPM, little or no vibration. Real smooth.

Third observation: It heats up QUICKER than the 4BT

Forth observation: Not squirrelly at 75MPH; steers and handles SO MUCH better.

Fifth observation: It is quieter than the 4BT; much.bounce

Sixth thing: The aftercooler does not stick out the hood as much as the 4BT crossover pipe.

Difficult task. Starter inop. Tore it apart, cleaned, wire brushed and lubed. Sixth cleaning and assembly and it works perfect.

Task now: re-seat engine and tranny rearward; re-install Taurus fan. Lower rear axle. Looks like it is standing on its nose.

Summary: You'd have thought it'd been as easy as pull one engine and drop the other in. NOT. :rolleyes:
Wayne
 

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What is it in? You are talking waterjacket aftercooler right?

my 4bta smokes a little bit... I haven't run it for more than a minute or two, but i can see a little haze after running it sometimes... could be because it sat for a while until now...

Mine shakes a lot when starting and on shutdown. I notice some vibs when it's idling, but it seems to smooth right out with a tap of the throttle.
 

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Discussion Starter #4 (Edited)
4BTA & No SMOKE

Engine is in 68 Bronco.
THM-475 -- D20 YES water-after cooler
23 gallon & 11 gallon tanks
D44 & 9" with 3:50 -- 35" tires = 2.78-1 ratio (81 @ gov)
Still gotta lower the rear end.
Still have to re-position the powerpack rearward.
When tranny drooped with no engine and I loosen mounts, it slipped forward 1.5".
Rearward movement should really give me the clearance over the D44.
Had my son rev the throttle, while I looked, and there is no smoke. None. Response is OK, it drove real smooth. Much better than the 4BT (which was no slouch). Better-cleaner.
Until I get the fan installed, driving is minimal. I can tell heat up is faster.
Made no pics.:dustin:
Wayne
 

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I am interested in how you modified the pan to clear the front axle. I've heard that it is possible to turn the pan around and run a front sump with some crossmember mods. I am trying to keep my bronco stock height so am looking for differernt ideas. Does the modified pan now hold less oil? If so how much less and will that affect the engine? Thanks
 

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DogDiesel, I'm heading From AZ to Ft. Bragg on 24JUN to pick up an aircraft. I may have a short lay-over @ Bragg. Any chance I could get a glimps of your project ( I see Lumber Bridge is about 30 mile away)? I recently picked up a 4BTA for my '69 EB and also have questions on D44 axle/oil pan clearence. PM if able. Doug
 

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Discussion Starter #7
Sunday 24 june

Sure, if you come in the morning. I catch a flight to Texas in the afternoon. What about Saturday 23d? We can drive it around on Sat.
Wayne
 

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Discussion Starter #9
Compression Ratio

Definitely could tell there was difference in idle noise between my old 4BT and 4BTA. Opened the service manual, and found the compression ration is:

17.5:1 on the 4BT
16.5:1 on the 4BTA.
18.5:1 on natural aspirated 4B.

This explains the noise difference.
Wayne
 
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