Horsepower Rating For Turbo Charged 864 V8

[peteslagel]

Can someone tell me the factory horsepower rating for the turbocharged version of the 864 cu inch V8? Was there a twin turbo version as well as a single turbo?

Any additional info would be helpful, maximum boost pressure, etc.

Any problem with head gaskets on this motor?

Thanks,

Pete

[theakerstwo]

I remember the twin turbo set up but dont remember the hp.

[werkhorse]

I think i've posted this on here not that long ago but here it is again august 1969 spec's from the Mack manual

bottom right last 3 row's gives 3 non turbo and 1 single turbo rating

Click to enlarge

if your sight is bad they read as follow's

END864 = 255 @ 2300 rpm

END864B = 270 @ 2300 rpm

ENDD864 = 237 @ 2000 rpm

ENDT864 = 300 @ 2300 rpm

Edited June 14, 2008 by werkhorse

[peteslagel]

I think i've posted this on here not that long ago but here it is again august 1969 spec's from the Mack manual

bottom right last 3 row's gives 3 non turbo and 1 single turbo rating

Click to enlarge

if your sight is bad they read as follow's

END864 = 255 @ 2300 rpm

END864B = 270 @ 2300 rpm

ENDD864 = 237 @ 2000 rpm

ENDT864 = 300 @ 2300 rpm

Thanks for that. You guessed correctly, sight is bad. Is it possible to get a clearer picture of that sheet. Is the turbo compression ratio lower than the non-turbo?

Pete

[werkhorse]

ok here ya go

Comp ratio's

END864,END864B,ENDD864 = 16.8:1

ENDT864 = 15.2:1

[ducky698]

i have been told of people getting 500hp out of these old 864,865,866 engines, how?

regards Grant

[Mack Doctor Jr.]

I think the twin turbo set up was 375 hp. It was 325 for single.

[theakerstwo]

I think the twin turbo set up was 375 hp. It was 325 for single.

I dont think it was that hi because the twin was before the single set up came out and most time hp goes up the next year instead going down.

[HK Trucking]

The ENDT866 was 375 H.P.

[skip]

i have been told of people getting 500hp out of these old 864,865,866 engines, how?

regards Grant

Gday all. I dont think you would get 500 out of an 864. Ive heard of a few 866s being taken out to 450-500. The 865 was a Maxidyne engine with lower hp than the 866 but more torque. I have heard of blokes using an E9 pump on an 866 but not an 865. As for the T864 the rotary pump was a bit troublesome and the twin turbo setup was fairly complicated so they canned them both and went for the single turbo and vee pump. The T864 was 300hp as already mentioned and out here the 864A was rated at 280hp in the R models and a few F models. Cheers skip

[peteslagel]

Gday all. I dont think you would get 500 out of an 864. Ive heard of a few 866s being taken out to 450-500. The 865 was a Maxidyne engine with lower hp than the 866 but more torque. I have heard of blokes using an E9 pump on an 866 but not an 865. As for the T864 the rotary pump was a bit troublesome and the twin turbo setup was fairly complicated so they canned them both and went for the single turbo and vee pump. The T864 was 300hp as already mentioned and out here the 864A was rated at 280hp in the R models and a few F models. Cheers skip

So the ENDT864 was the twin turbo?

Did the 865 and 866 have the same compression ratio as the ENDT864, and the same piston?

Is it possible to install a an E9 injectors into the 866 head?

Will E9 exhaust manifolds work on the 866 head?

Pete

[skip]

So the ENDT864 was the twin turbo?

Did the 865 and 866 have the same compression ratio as the ENDT864, and the same piston?

Is it possible to install a an E9 injectors into the 866 head?

Will E9 exhaust manifolds work on the 866 head?

Pete

How are ya mate? E9 injector wont fit into a 2 valve head. It goes in between the valves under the tappet covers whereas an 865/6 goes in on a slant outside the tappet cover, like a 6cyl 2 valve. E9 exhaust wont fit an 864/5/6. They have 4 ports per side whereas the old ones only had 2. And the 865/5 manifold wont go on an 864 either, as they have 4 bolt holes instead of 2. A pain in the arse.

I have never seen a T864 so I couldnt comment on compression ratio or piston type, but I would nearly be certain the pistons wont be interchangeable with an 865/6. The 864 series was always grouped with the 711 series. While the block and front cover looks similar between the 2 V8s there arent too many parts that are interchangeable. The Auxilliary drive was similar and you can put a Vee pump on an 864 but there was a different housing on some 865s just to make life complicated. Hope that rant wasnt too painful. Good onya mate. Skip

[peteslagel]

How are ya mate? E9 injector wont fit into a 2 valve head. It goes in between the valves under the tappet covers whereas an 865/6 goes in on a slant outside the tappet cover, like a 6cyl 2 valve. E9 exhaust wont fit an 864/5/6. They have 4 ports per side whereas the old ones only had 2. And the 865/5 manifold wont go on an 864 either, as they have 4 bolt holes instead of 2. A pain in the arse.

I have never seen a T864 so I couldnt comment on compression ratio or piston type, but I would nearly be certain the pistons wont be interchangeable with an 865/6. The 864 series was always grouped with the 711 series. While the block and front cover looks similar between the 2 V8s there arent too many parts that are interchangeable. The Auxilliary drive was similar and you can put a Vee pump on an 864 but there was a different housing on some 865s just to make life complicated. Hope that rant wasnt too painful. Good onya mate. Skip

Thanks Skip,

Very informative. I did not appreciate the difference between the 864 and the 865/866.

Can you comment on the head gasket question? Was there a problem with blown head gaskets on these old motors? Do the 864 or 865/866 have fire rings?

Pete

[skip]

Thanks Skip,

Very informative. I did not appreciate the difference between the 864 and the 865/866.

Can you comment on the head gasket question? Was there a problem with blown head gaskets on these old motors? Do the 864 or 865/866 have fire rings?

Pete

Im not totally sure on the motors doing head gaskets, there arent many around here any more. The 865/6 had a bit of trouble if heads werent re-torqued periodically. I think a lot of blokes out here used to re-torque them around 50-60thousand Kms. Im not sure about the 864, but every block Ive seen has major shuffle marks on the deck surface, so I would say they were in the same boat. The 864s also cracked around the counter bores and between the counter bore and some head stud holes, as there is only about 3/16" surface area. They have fire rings. Ive just had a block repaired and we paid really close attention to these areas I mentioned. Do you have a T864? There were only ever 2 or 3 in Australia. The only one Ive seen is on ebay in an R719.

[peteslagel]

Im not totally sure on the motors doing head gaskets, there arent many around here any more. The 865/6 had a bit of trouble if heads werent re-torqued periodically. I think a lot of blokes out here used to re-torque them around 50-60thousand Kms. Im not sure about the 864, but every block Ive seen has major shuffle marks on the deck surface, so I would say they were in the same boat. The 864s also cracked around the counter bores and between the counter bore and some head stud holes, as there is only about 3/16" surface area. They have fire rings. Ive just had a block repaired and we paid really close attention to these areas I mentioned. Do you have a T864? There were only ever 2 or 3 in Australia. The only one Ive seen is on ebay in an R719.

I am looking at buying a truck with a T864 in it. I had trouble with a 711 back in the late 70's and I went back to the 673. The 711 cracked between the two counterbores. I am concerned I might have the same problem with the 864. I need to use it for about 20k loaded miles a years, so I need it hold up, not just be a "show" truck.

Seems like I should look for an 866 for a backup.

On a related topic, did the 864 and 865/866 have a Mack single disk clutch? Can you replace the Mack clutch with a Spicer angle spring? Do you have to replace the rear housing and move the transmission mounting brackets?

[ducky698]

I am looking at buying a truck with a T864 in it. I had trouble with a 711 back in the late 70's and I went back to the 673. The 711 cracked between the two counterbores. I am concerned I might have the same problem with the 864. I need to use it for about 20k loaded miles a years, so I need it hold up, not just be a "show" truck.

Seems like I should look for an 866 for a backup.

On a related topic, did the 864 and 865/866 have a Mack single disk clutch? Can you replace the Mack clutch with a Spicer angle spring? Do you have to replace the rear housing and move the transmission mounting brackets?

My 866 has a twin disc spicer bolted to it, its a 15.5 inch. it all looks standard mack bellhousing on the 12 speed and the truck was rated to 90 tons

regards Grant

[jcharb]

I am looking at buying a truck with a T864 in it. I had trouble with a 711 back in the late 70's and I went back to the 673. The 711 cracked between the two counterbores. I am concerned I might have the same problem with the 864. I need to use it for about 20k loaded miles a years, so I need it hold up, not just be a "show" truck.

Seems like I should look for an 866 for a backup.

On a related topic, did the 864 and 865/866 have a Mack single disk clutch? Can you replace the Mack clutch with a Spicer angle spring? Do you have to replace the rear housing and move the transmission mounting brackets?

I have a 71 F model with a end864 (naturally aspirated ) It has a spicer twin disk . The head gaskets do not have fire rings. I took mine off the road, its to hard to get parts for the 864. I even bought a complete engine for it, just for parts. The truck is all original, I have line sheet for it. I now use it for a boom truck in the shop.

[skip]

I have a 71 F model with a end864 (naturally aspirated ) It has a spicer twin disk . The head gaskets do not have fire rings. I took mine off the road, its to hard to get parts for the 864. I even bought a complete engine for it, just for parts. The truck is all original, I have line sheet for it. I now use it for a boom truck in the shop.

Where are you based mate? I thought they had fire rings, Ive got a set of gaskets there and Im sure that they have removable rings. I must be wrong. Thanks for that. Has that been changed to a twin plate? I have a 71 F785 with a cable operated push clutch. Skip

[jcharb]

Where are you based mate? I thought they had fire rings, Ive got a set of gaskets there and Im sure that they have removable rings. I must be wrong. Thanks for that. Has that been changed to a twin plate? I have a 71 F785 with a cable operated push clutch. Skip

I am out Fla.The line sheet for the truck shows it came with the spicer pull type clutch.

[ducky698]

I am out Fla.The line sheet for the truck shows it came with the spicer pull type clutch.

my f model was cable operated pull clutch.

Grant