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T78 Rb25Det

r31 25t

By r31 25t,
in Engines & Forced Induction

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Harey Veteran

Harey

Posted
Posted

Twin scroll with be best.

I run a single scroll equal length love fab turbo header with a tial 60mm wg.

Spool test was at .7 bar no boost controller.

Results was:

5 psi at 3,200 rpm

10 psi at 4,300 rpm

Which was fool boost

We set our rev limit to 5,000 rpm

Which was hitting rev limit at 4,800rpm

You can check out Kelford camshafts

They use a lower lift but the same duration as my tomei.

Mine is 10.25 both camshafts

They do help spool

Why the super low boost level and rev limiter?? Are you running the engine in?

meet07 Enthusiast

meet07

Posted
Posted

Twin scroll with be best.

I run a single scroll equal length love fab turbo header with a tial 60mm wg.

Spool test was at .7 bar no boost controller.

Results was:

5 psi at 3,200 rpm

10 psi at 4,300 rpm

Which was fool boost

We set our rev limit to 5,000 rpm

Which was hitting rev limit at 4,800rpm

You can check out Kelford camshafts

They use a lower lift but the same duration as my tomei.

Mine is 10.25 both camshafts

They do help spool

Kelfords camshaft listing for the rb25 is kinda unclear. It shows hydrilic lifters but says that its not suitable for the r33 an r34 with nvcs. So will these drop right into a series 1 rb25det with hydros...? No springs or solid lifters right....?

N1GTR Grand Master

N1GTR

Posted
Posted

Why only 22psi? Just keep screwing more in until it stops making power or you run into detonation issues.

This is probably the smartest post of yours on SAU.

Why people stop at a certain number they get stuck in their heads is just STUPID

koe Contributor

koe

Posted
Posted

Lol

A high boost T78 will Demand tire changes like you wouldn't believe.

The demand wide rims to have atleast a 275 or a 300 wide tire to be able to find some grip.

This means rims less the 10j are useless unless you can afford good sticky dot tires with treadware 100 or less.

Plan ahead and get ready to spend some good cash on suspension and wheels/tires.

Learn how suspension works.

Become a expert in spring rates etc.

The more you know the less money you waste.

That's my 2cents

Roy Grand Master

Roy

Posted
Posted

Why people stop at a certain number they get stuck in their heads is just STUPID

Ahh, whats stupid about it? A std engine with 9.0:1 compression on PULP98 is going to fall victim the laws of physics if you lean on it too hard.

A std 9.0:1 compression bottom end isnt going to like too many revs, too much boost or too much power in general. Mix all three together and you have to accept that the state you are running your engine in may result in a faiulure.

Keep revs to below 7,800rpm, boost under 20psi and I suspect the thing will be pretty reliable even if its making 360rwks. Run 24psi and the risk simply increases

Rolls Grand Master

Rolls

Posted
Posted (edited)

Keep revs to below 7,800rpm, boost under 20psi and I suspect the thing will be pretty reliable even if its making 360rwks. Run 24psi and the risk simply increases

Why 20psi, why not keep it under 18psi?

You are guessing, really need to put it on the dyno and see how it behaves, if it doesn't detonate or get hot then what is the issue?

Edited by Rolls
  • 1 year later...
r31 25t Contributor

r31 25t

Posted
  • Author
Posted

Update time.

Made 300kw on 16-17psi and e85.

I did end up with more but i was running out of fuel. I think it's time for a new fuel filter.

Will retune on 98 and e85 with more boost a bit down the track.

Out of interest what plugs should i be running?

What sort of timing no's should i expect up top? Currently it's around 17-18deg.

Thanks

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