Another compound build.

[chaclark83]

Hey guys. Im starting a compound turbo build for my 95 talon. A little background the engine will be a 6bolt with wiseco 10.5 hd pistons on pauter rods. Head has 1mm ferrea valves and some mild port work with my home made smim. It will be fed copious amounts of E85 most likely with dual intank walboros and 2150 fic hi z's. The small turbo will be a 14b to start so It can be upgraded to a 16g later if needed. Now the questions are for the larger turbo (hx40) should i be looking for a 6, 7, or 8 blade. What exhaust housing would work best on it? Also for space and price reasons do you guys think the 50mm wastegate from synapse would flow enough around the first turbo to keep creep down on it? Thanks for any input.

 

[Miasma]

Hey guys. Im starting a compound turbo build for my 95 talon. A little background the engine will be a 6bolt with wiseco 10.5 hd pistons on pauter rods. Head has 1mm ferrea valves and some mild port work with my home made smim. It will be fed copious amounts of E85 most likely with dual intank walboros and 2150 fic hi z's. The small turbo will be a 14b to start so It can be upgraded to a 16g later if needed. Now the questions are for the larger turbo (hx40) should i be looking for a 6, 7, or 8 blade. What exhaust housing would work best on it? Also for space and price reasons do you guys think the 50mm wastegate from synapse would flow enough around the first turbo to keep creep down on it? Thanks for any input.

What are your power band expectations. My compound setup is a gt25r and 35/40r hybrid.

You need to consider how much air your 14b is going to be able to feed your larger turbo with out choking. You need to put a lot of thought into which turbo`s you go with, and make sure you have a good balance in your maps. What is your altitude? Best way to think about it smallest ar. housing on your primary with largest ar. on your secondary turbo while considering your lbs/min air flow. With my 25r I will be using a ar.42 and the hybrid is a ar.78.

Make sure you when you build your manifold that your wastgate from your primary feeds your secondary turbo exhuast inlet, and then what you do with your secondary wastegate is your preference.

 

[chaclark83]

I know and understand how the setup works. What do you mean by flow enough air without choking? The compressor doesn't feed the larger turbo and if you are referring to the hot side a large enough waste gate would flow enough to keep back pressure down. That is what I was asking. Does anybody think the synapse 50mm gate would flow enough or should I just throw out 500 for a tial 60mm. I haven't personally used synapse but I've heard they flow better than tial. I appreciate your response.

 

[Miasma]

Atmospher -> hx40 compressor -> 14g compressor -> engine, exhaust -> 14g turbine -> hx 40 turbine -> atmosphere.

What I am meaning by choking is that your 14g needs to flow enough exhaust into your hx40 to continue boosting without to much back pressure. Depending on your setup you should be able to geat away with it. I honestly haven't used the synapse wastegate, I've only used Tial gates.

But I was also saying on a compound setup it is better to use two gates. The first coming off your 14g flowing into the exhaust housing of the hx40 to keep your spool up, and then the second coming off your hx40. Your exhaust housings need to be balanced between the two turbo to maxime lb/min airflow. Not to wide spread, but not to close together.

What are you planning to run on as your hx40?

 

[chaclark83]

Yes there will be two gates. Another 40mm will be coming off the hx40. What do you mean what am I planning to run on as my hx40? And yes you are correct that it has to flow enough to keep from choking or creating excess back pressure but what I'm trying to explain is that if you have a big enough Watergate on the smaller turbo it won't matter because the gate will let it flow enough.

 

[Miasma]

Was wondering what size exhaust housing you are going with on your hx40. I'd check out some flow maps see if I could give you anymore info. But sounds like you got the right idea then.

 

[chaclark83]

Yeah man. I've built compound setups on several oil burners. Just looking for experience on DSM specific builds.