janrx7

A friend is selling me a Precision T67 ball bearing turbo with a 0.81 hotside. I believe this is the same t04r turbo. In addition he is giving me a 40mm tial wastegate. All this for $800 bucks.

Question
1- IF the mods in my signature (i have a dowel engine) @17psi with race gas could i achieve over 425whp? i think i may need larger injectors.
2-What would be the peak hp a turbo with this hotside can make? Peak psi?
3-Is the 40mm too small?

silverfdturbo6port

iTrader: (26)

yea you could achieve that if you have a good tuner that is.

janrx7

What would be he max whp that a t67 with a 0.81 hotside could make? 450whp? Is the 0.81 hotside too small for a streetported engine?

Is a 40mm wastegate too small for this?

Dudemaaanownsanrx7

iTrader: (23)

You might be able to make over 425 at 17psi. That housing is a little on the small side, but it will still make the power, just the upper RPMs will start choking especially at higher boost levels. Your Power band will be shifted down in RPMs. Try the wastegate and see. It really depends on how well the manifold is made and how direct the path is to the wastgate, and if it's plumbed back into the system. But higher boost levels will require less from the wastegate since it will be using the exhaust gas to keep the turbo moving. If you were to run enough boost you wouldn't even need a wastegate. haha

RacerXtreme7

iTrader: (2)

That turbo and wastegate will do it, but your going to need more fuel then you currently have. You sould beable to make 400 RWHP or better @ around 1 bar of boost (14~15 psi) on pump gas.

~Mike............

janrx7

My injector duty was about 80% at 365whp. I think i could manage just over 400whp @95% duty cycle. I have a denso supra pump and rewired job. This helped alot my duty cycle. I planned to put 1600cc secondaries in the near future

Dudemaaanownsanrx7

iTrader: (23)

You can always increase the base pressure with an aftermarket fpr. Square root of (new pressure divided by old pressure), x old flow = new flow.

janrx7

I don't have a FPR. With this could i lower my duty cycle? Which do you recommend aeromotive?

janrx7

Already bought the turbo and wastegate. Going to build a custom stainless steel manifold and downpipe. THe idea is, with a custom manifold, we can put the turbo whenever we want, oppose to buying a chinese manifolf on ebay, and the put goes where it goes.

I am converting to single in 2 months. Saving up rest of the money.

Dudemaaanownsanrx7

iTrader: (23)

Yes you can lower your duty cycle with higher fuel pressure. I'm running aeromotive. They also have a build in fuel pulsation dampner so you can get rid of the stock one which is prone to leaking.

janrx7

I am debating b/w 1600cc secondaries or 1000cc secondaries. I am inclining to the 1000cc because my someone told me that we could put them without the use of a fuel rail. (I managed to put 850cc primaries without fuel rail.) Is this posible?

Also he told me that 1600cc would be overkill for my power level (470whp). Any inputs?

RacerXtreme7

iTrader: (2)

Stop listening to him, for you power goal of 470 WHP your going to need those 1600cc injectors. Is he a piston guy telling you this?

~Mike.............

janrx7

yes he works mainly with pistons. I know rotary love fuel so 850/1600cc combo should be.

Dudemaaanownsanrx7

iTrader: (23)

Yeah you should go with the 1680 injectors, you might be able to get by with 850 1000 but it would require a much higher base pressure. The secondaries that people usually go with to keep the stock rail is either 1200 or 1300cc and are stock 850's drilled out. I've already had a stock primary injector fail once for no reason so i don't think drilling out old stock injectors is a good way to do it. I'm running 550/1680 with higher base pressure and its enough fuel for over 500 rwhp.

janrx7

Going single next week, doing a custom stainless steel manifold. Bought the 13b flange from racing beat and a flange for t4 inlet ftom ATP. Aim is for at least 400whp @ 15-16psi with Sunoco Race Gas. Going to maxed out my injectors to 90-95% duty.

In the near future adding a Aeromotive FPR and 1600cc injectors. Keep you posted with results.

janrx7

just came from dyno. Managed 429whp@15psi with sunoco racing gas. Car could have made more power but due to some reason the boost controller or wastegate had a problem controlling the psi. i have a tail 40mm wastegate and i may have to change the spring. or maybe my problem is my greddy profec . i am really happy with the results.

janrx7

my tial 40mm wastegate doesn't give me less than 15psi. I want to have 10-11psi on the street and 15psi on the track. Should i change my wastegate spring? should i change the wastegate? the smaller the wastegate 40mm for example the more boost it controls?

TweakGames

iTrader: (3)

Hello, I'm sorry I may have missed it, but what spring do you have in currently? If you have a 15 lb spring in there, you can't go under 15, all a boost controller can do is to UP from the spring. If you want to have 10-11 on the street and 15 psi on the track you will have to have either right at 10 psi, or slightly under 10 psi spring. I would get something like a 8-9 lb in case you want to run even less boost some day, and have the boost controller control the 10-11 street, and 15 track.

People get their boost controllers installed incorrectly quite frequently. Triple check the wiring and hoses. Also, do not trust someone else telling you what spring you have in there, physically open it up, and check the color of the spring vs the tial website. Also check the spring, as some people try weird things cutting the spring trying to make it softer and such.

I was running a 5 lb spring on my tial 38 mm running a pt67 (not BB) and I could easily control anywhere from 5-11 psi. I never went over 11 as I was going for reliability. Sadly the engine blew because of bad porting. I will be going for the magic 15 psi hopefully in 2 weeks when all the parts get here for the rebuild.

P.S. Great power for the PSI, I'm going for 400 on this next build, you give me hope! If you could, post the dyno sheet, I would love to see when the torque hits on your build.

~Tweak

Turblown

iTrader: (12)

If you were making the power you should have been making I bet you wouldn't have been able to control boost that well..

janrx7

thanks. already downloaded tial spring combinations. going to check the colors on my wastegate. Hope i can control to 10psi. I have the dyno sheet, but have torque only whp.

TweakGames

iTrader: (3)

Sorry I don't understand what you are trying to say. What power should I have been making? I was able to control it with both my haltech boost controller (once I figured out all the silly settings), AND my c02 power boost controller quite easily. I'm just confused on what you are saying, sorry.

project3328

iTrader: (1)

hes basically saying its easy to control boost if ur not boosting all that much

arghx

iTrader: (3)

I couldn't control boost with a 10psi spring on an HKS 40mm gate with HKS log manifold... this was running wastegate pressure with no controller

TweakGames

iTrader: (3)

Weird..... Maybe I am just lucky.

Turblown

iTrader: (12)

You weren't lucky. When you're not making a lot of power you simply just don't have the exhaust flow. Less exhaust flow, easier it is to control lower boost levels.