8.1 liter big block Chevy

[lilbowtie]

"I never drove a screaming Jimmy, man do they sound cool."

The 53 series were known as the screaming jimmies - Imagine next to one @ 3200 - 3400 no load

 

[Turbo Zach]

"I never drove a screaming Jimmy, man do they sound cool."

The 53 series were known as the screaming jimmies - Imagine next to one @ 3200 - 3400 no load

I have spent a lot of time around them twostroke diesels. I have rebuilt probably at least a dozen four cylinders. My last job we used to rebuild the 370 Trashmaster trash compactors. They use a v8 Detroit and are hydrostatic drive. They don't move until you get the RPMs up. How would you like to run that all day? Sorry for the hyjack. Do they make a carb intake for those 8.1 engines?

 

[454GrandPrix]

FYI - 8.1 have a well known oil consumption issue.

I will verify this. Especially when you work it hard, my 8.1L does consume a little oil. It isn't terribly excessive in my opinion. When I towed my Jeep to CA to run the Rubicon trail, I left home (Salt Lake City) with a full crankcase; when we stopped in Reno for fuel, I was at the 'add' line and put one quart in. That was over 500 miles, doing 75 MPH all the way (I was in a caravan of three tow rigs, with a leader who likes to hustle). I didn't think that was asking too much.

FYI

 

[bob64]

The oil consumption is always the same, faulty intake gasket an normally back right side. I had this with mine also an many have had it happen also. New gasket and away ya go.

 

[lilbowtie]

I have spent a lot of time around them twostroke diesels

45 years for me @ Detroit Diesel engineering.

 

[Clutch]

I have spent a lot of time around them twostroke diesels. I have rebuilt probably at least a dozen four cylinders. My last job we used to rebuild the 370 Trashmaster trash compactors. They use a v8 Detroit and are hydrostatic drive. They don't move until you get the RPMs up. How would you like to run that all day? Sorry for the hyjack. Do they make a carb intake for those 8.1 engines?

Yes dart makes one and when used you can pull the oil pump drive and drop in a Chevy distributor

 

[csstrux]

I like the L6 concept, but would steer clear of the 3116 Cat. They are know to be problematic. I have been toying with the idea of a TBI crew cab dually with a Cummins swap myself. Once I find the right chassis. Some day.

 

[Clutch]

I like the L6 concept, but would steer clear of the 3116 Cat. They are know to be problematic. I have been toying with the idea of a TBI crew cab dually with a Cummins swap myself. Once I find the right chassis. Some day.

I looked for years before I bought my baskit case lol but it's starting to come together. The now idea of an 8100 Vortec is because I don't think my 350 is going to make the long haul it dose the job but it's bordering on problematic. But so is the rest of the truck

 

[CaliWagon83]

What engine is it? 8.1 there are afew different years an actual cubes.

I have a 502 HT Vortec bbc in a 16000lb RV with 400th an 19" rims & 32"tires an l believe 4.10's, with trailer on behind an you punch it she will roll the tires. Gas mileage suck's 12mpg empty an 10mpg pulling a 32' car trailer load an that's driving at 55mpg. Everything's forged internals. 406hp/541tq in my 502. This engine is basically a 454 punched out, well sort of.
I actually pulled it out to put in my Monty SS.

The 8.1 Vortec your talking about(l believe) is basically a stroked 454 an 60 over with forged internals, l have one of them also, that started in a Truck but now is in one of my cars. Alot of fun, cops hate it an bad gas mileage with either fuel injection or carb. Best l ever got was 10.5mpg in a car an that's with a 4L80E, it got 6mpg with the 400th.

I also have a 468(454) in another car that gets 14mpg(4L60E)an l think it's guessing but a good 400hp an she's got a snap to her. But nothing forged.

There all 4 bolt mains an if l had to pick an engine to throw in a truck l'd go with the plain Jane 454bbc for simple reasons, cheap parts an easy of finding them. The vortecs are really expensive to build up.

A 4L80E is basically a 400th with an extra gear, an you will want that extra gear to come to that 80mph you want. 400th will do it but it will be screaming an they don't like that an neither will you wallet.

You want to cheap out use a toggle switch for lock up on the 4L80E or 85.

View attachment 100553

Those figures for the earlier-year Duramax are not correct. the LB7 had 300 hp/520 lb-ft when it launched. The vans were down-rated because they used the 4L85 and later the 6L90 rather than the Allison, but the HP figures are low for the DMax, unless those are for the fleet vehicles, which are rated differently.

 

[Clutch]

Those figures for the earlier-year Duramax are not correct. the LB7 had 300 hp/520 lb-ft when it launched. The vans were down-rated because they used the 4L85 and later the 6L90 rather than the Allison, but the HP figures are low for the DMax, unless those are for the fleet vehicles, which are rated differently.

I can't afford a Duramax swap anyway. I'm liking what I'm hearing about the 8.1 tho priority oiling forged internals no valve angle issues like an old big block sounds like a good truck motor to me.