Reverse Hybrid Hx 35/40

[6.2 turbo]

I home built a HX 35/40 . It has the 54/78 mm 7 blade compressor and 76/64 10 blade turbine in a 18 cm housing . It wont light under 2000 rpms, and so far max boost of 23 psi with waste gate disconnected. So far I'm quiet happy with it,more power under the turbo and lots more 3k and up . This is compared to a 54 mm H1C with 12 cm housing .

 

[bowtiebutler956]

Interesting. Why did you choose to do it the other way around, and why not just use the HX40's compressor side as well, rather than the smaller 35? Was it so you wouldn't have to run a wastegate, and still keep the boost from getting to crazy? Not that 23 isn't already quite high. I'm running in the 20-25 range myself.

Matt

 

[6.2 turbo]

The smaller inducer compressor lets the turbine flow better/turn easier . Same idea as the Banks and ATT turbos.

 

[bowtiebutler956]

The smaller inducer compressor lets the turbine flow better/turn easier . Same idea as the Banks and ATT turbos.

Very good. Which one of your trucks is this on. I notice that your signature says your 92 has spun bearings, but your in the process of a 6.5 conversion on your 96 Tahoe.

Matt

 

[6.2 turbo]

Its in the Tahoe , a 6.2 L , my signature needs updated. This vehicle has seen a lot of engines ,and the current one has a lot of blow by,and a slight head gasket leak. It is also converted to a 5spd nv3500.

 

[Jorge6.5]

Its in the Tahoe , a 6.2 L , my signature needs updated. This vehicle has seen a lot of engines ,and the current one has a lot of blow by,and a slight head gasket leak. It is also converted to a 5spd nv3500.

What clutch and flywheel set up did you use to mate the nv3500 to the 6.2? Thanks

 

[bowtiebutler956]

Its in the Tahoe , a 6.2 L , my signature needs updated. This vehicle has seen a lot of engines ,and the current one has a lot of blow by,and a slight head gasket leak. It is also converted to a 5spd nv3500.

Thats awesome, I've never seen a 5 speed Tahoe. Is the NV3500 holding up ok with the torque of the diesel? Are you planning on refreshing the 6.2 anytime soon?

Matt

 

[6.2 turbo]

Its holding up better than the 4l80-e,which broke an input shaft,shifting with tcc locked. I'll probably build one of my other engines ,and swap it sometime. Probably wait until the head gaskets blow for real,only warning signs now. The block is pitted at the fire ring which has made this engine difficult to seal.

 

[bowtiebutler956]

Its holding up better than the 4l80-e,which broke an input shaft,shifting with tcc locked. I'll probably build one of my other engines ,and swap it sometime. Probably wait until the head gaskets blow for real,only warning signs now. The block is pitted at the fire ring which has made this engine difficult to seal.

I'll keep that in mind, as I just did the manual TCC mod to my truck because I have 3.42's, and when I'm towing heavy, its more ideal in 3rd, but on my truck, my TCC wouldn't lock in 3rd, just OD. The shifts are very strange if you leave the switch on accidentally.

 

[6.2 turbo]

I'm using small block Chevy flywheel and a Hays kevlar clutch. Just need to swap the ring gear and weld the weight on. The flywheel is steel ,not cast iron. Played with the pump a little,and had the engine run wild for me about 4 or 5 k,untill I got it shut of with a board. The turbo has made 30 psi on the last test drive.

 

[pacificdrumma]

Makes sense... HX35 exhaust housing can be restrictive IMO

 

[6.2 turbo]

Its not wild,but runs way better than it did with the H1C,which had the same size inducer compressor. I tried 12/16 and 18cm housings on the H1C and none of them changed power in 3-4 k range.

 

[turbovanman]

Are you measuring drive pressures? Out of all the compressor wheels I've tried, the stock cast 60x86 has been the best, cleaned up all my smoke and off idle, tons of power. I haven't really revved it out yet as my engine is making some weird noises and need it to last a few more months. The billet 60mm extended tip wheel moved the powerband up, was great for high rpm, lol. I have a 14cm housing I'll try before i swap engines. Current drive pressure averages 1.7:1.

 

[6.2 turbo]

I didn't check drive psi. It smokes a lot even after its lit at 2000 rpms, but just slight black haze 3000 rpms and up. The ip has my favorite cam ring, a 4500 rpm gov spring ,and custom retard cam. It still has stock charge psi,which is probably only 80 psi at full fuel.

 

[turbovanman]

I bet if you tried a larger wheel, it would clear up a ton of that smoke. Best thing about Holsets, wheel are super easy to change out.

 

[6.2 turbo]

I have a 60 mm ,and the matching cover. Might try it sometime. It don't smoke if I'm driving part throttle,and has good power @ 0 boost. I'm running the small precups,which give the most power and torque under the turbo.