Turbo Guru Needed TE45A vs 6765

[R&C_rallySyTy]

Just wanted to see the major difference between these two turbos.

My old setup had a TE45a (66 intake wheel, with a 63 Precision exhaust) This was a standard bearing turbo.

Compare the TE45a to possible a new purchase:

Precision 6765 H cover 4" in and 3" out, .85 exhaust 65mm F1 type wheel in dual ball bearing / oil and water cooled.

This is for a 4.3 Syclone motor fully built with forged internals. Has Brodix heads full port and polish. Going to run 22-24psi on alky injection with a big a/a IC on 93 pump.

 

[Sweet6]

I think total power will be about the same. The BB version will spool a lot faster. I went from an old 63(45) to a BB66 and the 66 may run the same as the old 63 on 1lb less boost. It does spool faster. So the swap was worth it in that regard. But I did not see much if any power gain. I did the swap for the spool up anyway.

 

[R&C_rallySyTy]

I think total power will be about the same. The BB version will spool a lot faster. I went from an old 63(45) to a BB66 and the 66 may run the same as the old 63 on 1lb less boost. It does spool faster. So the swap was worth it in that regard. But I did not see much if any power gain. I did the swap for the spool up anyway.

I don't even know what size mm a TE45A turbo is. Keep in mind this is on a Syclone motor. 4.3 bore 30 over with forged everything and some great brodix heads. My old TE45A was lacking on the exhaust side which was a 63 a/r. The .85 a/r with the 67 should help open that up. I'm having some real issues choosing a turbocharger

 

[Sweet6]

The TE45 is a 66MM. Good for mid to low 10s in general. The 6765 will yield the same results. But it will spool way faster if you got a BB version.

I think both the TE45a and the 6775 are very similar. Just the 6765 can be had in a BB version. The 6765 may make more power. But not much of a difference I don't think.

 

[RUQWKNF]

TE45A used a TO4E style compressor cover, 66mm compressor wheel and a P-trim turbine wheel. It was rated to support 700 flywheel hp.

That new 6765 should support 800 flywheel hp when maxed out and spool up faster. IMO, if you are looking to make 650-700 awhp, that 6765 will get the job done. If you are looking to make more than that, you will have to step up the turbo size.

HTH

Patrick

 

[Sweet6]

Good info Patrick.

I have a buddy who has a 6765 DBB and I ran a tad faster with my old 63. Boost was about the same. 28-29lbs on stock GN motors. Both cars had similar bolt ons. His spooled up waaay faster than mine. I drove and tuned both cars. I did not see a big power difference between the two turbos. At least on stock motor cars. But the spool was night and day different.

 

[gnloyalty877]

I went from a 45a to the bb6765 and what they guys say is sooo right. Spoolup in night and day. Power feels the same. I ran an ac nl 3500stall with the 45 and thats too loose for the 67 which i'm having dusty do a little tighter one.

 

[R&C_rallySyTy]

The TE45a only having a 63 exhaust side comapred to the 6765 having a .85 a/r should also make a big differance for me correct? Or am I missing something.

What is the difference between the HPQ/GTQ type 6765s comared to the 6765 I mentioned above. Never really did understand those letters after the numbers? PTE6765 is much differant from a 6765HPQ?

 

[bison]

The TE45a only having a 63 exhaust side comapred to the 6765 having a .85 a/r should also make a big differance for me correct? Or am I missing something.

What is the difference between the HPQ/GTQ type 6765s comared to the 6765 I mentioned above. Never really did understand those letters after the numbers? PTE6765 is much differant from a 6765HPQ?

You have to specify which housing you want since anyone could be ordered with any of the housings you mentioned. There is no such thing as a 6765HPQ. Only 67HPQ. GTQ/HPQ is a completely different turbine. 65 trim turbine replaces the 76 trim and flows a little more. Not sure how much more but probably not much in a 3 bolt housing. Ive never seen a 6765 maxed out on a Buick or a back pressure test with both trim in the same a/r housing data logged so its hard to say with any accuracy what the 65 trim is worth over a 76 trim. My guess would be 10-15hp on an engine capable of making 600+hp. The HPQ has proven to make a lot more than a 76 trim when run hard. Like 80-100hp more.

 

[R&C_rallySyTy]

You have to specify which housing you want since anyone could be ordered with any of the housings you mentioned. There is no such thing as a 6765HPQ. Only 67HPQ. GTQ/HPQ is a completely different turbine. 65 trim turbine replaces the 76 trim and flows a little more. Not sure how much more but probably not much in a 3 bolt housing. Ive never seen a 6765 maxed out on a Buick or a back pressure test with both trim in the same a/r housing data logged so its hard to say with any accuracy what the 65 trim is worth over a 76 trim. My guess would be 10-15hp on an engine capable of making 600+hp. The HPQ has proven to make a lot more than a 76 trim when run hard. Like 80-100hp more.

The 6765 has a new P-trim. The TE45a has an old P-trim. Also the 6765 has a bigger inlet and outlet.

 

[bison]

The 6765 has a new P-trim. The TE45a has an old P-trim. Also the 6765 has a bigger inlet and outlet.

I already mentioned the turbine differences. The 65 replaces the p-trim and the 6765 doesnt necessarily have a larger cover. The 6765 could be ordered with the following compressor covers and id think the same could be ordered for the 45a. Id also bet that Precision could use the 65 turbine with the 66 compressor thats in the 45a and the various covers available. Ive seen E and S covers on the 45a.

E 3" inlet, 2" outlet
S 4" inlet, 2.5" outlet
SP ported shroud 4" inlet, 2.5" outlet
H 4' inlet, 3" outlet
HPS ported shroud 4" inlet, 3" outlet
HB H cover with a pressed on 6" inlet bell

 

[R&C_rallySyTy]

I already mentioned the turbine differences. The 65 replaces the p-trim and the 6765 doesnt necessarily have a larger cover. The 6765 could be ordered with the following compressor covers and id think the same could be ordered for the 45a. Id also bet that Precision could use the 65 turbine with the 66 compressor thats in the 45a and the various covers available. Ive seen E and S covers on the 45a.

E 3" inlet, 2" outlet
S 4" inlet, 2.5" outlet
SP ported shroud 4" inlet, 2.5" outlet
H 4' inlet, 3" outlet
HPS ported shroud 4" inlet, 3" outlet
HB H cover with a pressed on 6" inlet bell

My old TE45A for sure had a E cover. The new DBB 6765 has a H. How much of a difference will that make with the bigger cover and larger .85 exhaust side?

 

[Darkcyde]

My old TE45A for sure had a E cover. The new DBB 6765 has a H. How much of a difference will that make with the bigger cover and larger .85 exhaust side?

more air = more power if you got the fuel and tune, not to mention the less restriction your new turbo has on the barring cartridge, and the fin designs

 

[Sweet6]

My old TE45A for sure had a E cover. The new DBB 6765 has a H. How much of a difference will that make with the bigger cover and larger .85 exhaust side?

I do not think you will see much of a difference. It will not hurt, but it will not be a night and day difference either. I went from an E cover 63 to a S cover 66 and did not see much of a difference. I would guess I may have picked up a tenth. I would go with what you want to do, just don't expect a big gain.

 

[bison]

My old TE45A for sure had a E cover. The new DBB 6765 has a H. How much of a difference will that make with the bigger cover and larger .85 exhaust side?

As Sweet6 said, probably not much. Even with the .85 housing you are still limited by excessive back pressure on the exhaust side. Put a gauge in the exhaust and post the pressures when you get up over 600hp. They will be very high. Tangential 4 bolt is the way to go to really be able to maximize the potential of the compressors/covers in question. The old 6776 was a solid mid 10 sec turbo on full weight TR's. You should see a decent gain with the .85 since you have a larger engine and were already really restricted though

 

[R&C_rallySyTy]

I think in comination of getting ride of the old water to air intercooler which was seeing heat soak quickly and going to a air to air should also help. That in comination with a dual ball bearing 6765 with a larger cover and bigger exhaust side should be a decent gain. Whatever I max out on with 24psi and alky injection I'm going to have to be happy with. Thanks for all the help guys!

 

[stagemonster]

did you ever sell that turbo

 

[R&C_rallySyTy]

did you ever sell that turbo

Yes, sold it to someone on the board. Ended up with around 500 bucks for it.

 

[DougsfastZ]

Yes, sold it to someone on the board. Ended up with around 500 bucks for it.

And it's been working real well so far.

 

[R&C_rallySyTy]

And it's been working real well so far.

Good to hear from you. Really joyful to see you are enjoying my old turbo. Would love to hear more details, did you pick up power? Better track times? I figured that would be a great turbo for a turbo Buick, it was to small of a A/R and exhaust side for my built 4.3L

Edit Post: Never mind, I see your sig. Looks like you picked up 2 mph trap speed but need bigger injectors and tighter converter, then with a tune and you should see some low 11 passes or better. Hell, with the old set up you had a 1.6 60" compared to the new setup and a 2.0. Correct me if I'm wrong, but the way it sits now without those other upgrades with a 1.6 60" you would gain about 8 tenths at the end. 12.4 - .8 = 11.6 which already beats your old set up. With the extra fuel and stall and a good launch we are going to see a black blurring rocket. Would like to see a high 10 in her.