200rwkw 4agte???

[Cuzzo]

couldnt be that much less than 200 on 18psi?!?!?!

Im making 150 on 12psi. on a different turbo yes. soooo

[YLD-16L]

I make approximately the same peak power with my current setup from 16psi through to 21psi, the only change is through the earlier parts of the power curve. I run 18psi as it gives a reasonable midrange and about 170rwkw peak power and the inlet temps remain acceptable.

My brothers 4AGTE had a larger turbo, made much more power than mine for the same or less boost but it just didn't have the same "feel" to drive - awesome car and a little quicker over the quarter but it was different, not as "toey" .

[kingmick]

a good HG and get some compression going might help u get there .. but this would contradict kingmick as a thicker HG is associated with lower comp ratio to safely run higher boost levels... (?)

" comp for the given boost you will want in the end"
if you want low boost like 15psi, up the Comp.If you want high boost over 25psi lower the Comp.
What was ment

[thechuckster]

430cc injectors (7mgte, I believe bolt in)

actually, 7mgte injectors are around the 375cc mark (going from memory hear) - so you'll definately want large larger (e.g. the aforementioned mazda units) squirters.

EDIT: the bit in italics about injector flow rate is wrong - it should say 440cc - i always get this wrong about 7mgte injectors - sorry.


Also, the 7mgte and 4azge injectors have a hard-to-find electrical connector, i think the RX7 units are a standard bosch injector. You should confirm that the bosch units have the same OD for the fuel rail and pintle ends - i think bosch are larger (at both ends) than standard denso injectors.

note: you can find bosch injectors in great supply at wreckers - V6 commodes and early magnas have robust and highly re-usable bosch injector electrical plugs - unlike the fragile and prone-to-cracking denso plugs.

[Cuzzo]

7MGTE are 440cc, (going from info on net, never had mine flow tested)

7mgte connector is very similar to smallport 4age injectors. Just the locating tabs need fileing down.

[RONA]

Google says 7mgte injectors are 440cc

[YLD-16L]

actually, 7mgte injectors are around the 375cc mark (going from memory hear)

The place I got my injectors from had 440cc written on each little box

i think the RX7 units are a standard bosch injector. You should confirm that the bosch units have the same OD for the fuel rail and pintle ends - i think bosch are larger (at both ends) than standard denso injectors.

I've had, the standard injectors, 440s and 550s all in and out of the standard rail/head no mods to diameter.

[adamaw11]

" comp for the given boost you will want in the end"
if you want low boost like 15psi, up the Comp.If you want high boost over 25psi lower the Comp.
What was ment

Could a high comp, lower boost setup be made to get the same power with less fuel?

I'm always just a little uncertain as to how exactly static compression ratio increases power. Since more boost adds more air so more fuel can be burned in the same space, but more static compression isn't adding more air? so is it just more of an explosion or something? more complete burn? or actually more fuel burnt with less air needed?

[jfallen]

unlikley, you'd run into knock problems.

the old Group B cars had static compressions ~7:1, so they could run 40+PSi of Boost. High compression will limit the amount of safe boost you can run, and thus limit your "peak" power.

Cheers
Jordan

[RONA]

http://www.initialdrift.com.au/forum...=asc&start=195

Car made 154rwkw on 12psi at 10.5:1 before a big end bearing failure

OK heres the final diagnosis of what we think happened at the DA rpound last week to my engine.. long story..

When we assembled the engine for turbo use, we did not touch the bottom end as it was presumed to be strong enough with the setup already in place, however when we put the sump back on from having the oil return plumbed into it, we noticed that the oil squirters in numbers one and three had broken the tips off, and could not find a reason why.....
during the day at oran last week, oil temp guage went through the roof and i stopped, then noticed the bearing knock in the engine and thought that the oil had gone to water and id therefore spun a bearing. We put it then down to bad oil.... BUT now the car is reassembled we have a differant theory...

Oil temp guage reads off the scale always, so the sender is broken, but thats what stopped me last week. we now think the clearances on the old crank were suspect to begin with and the turbo high comp setup just sped up the engines already begun demise.So result of the execise is that i now have a new crank and some trd rods inside, with bearing clearances of just 1.5 thou across the board ( thank god we tracked down a new 100 kw crank over the weekend thanks NATHAN) and we are in the process of sorting out the guage. car fired first crank last night after running on the starter for a few mins to get oil pressure up, and sounds just as insane as before, so now it is time to let the fun begin and lets go INDY!

[Ben Wilson]

unlikley, you'd run into knock problems.

the old Group B cars had static compressions ~7:1, so they could run 40+PSi of Boost. High compression will limit the amount of safe boost you can run, and thus limit your "peak" power.

Cheers
Jordan

I'm also sure they weren't running on pump fuel...

[adamaw11]

lets just say you could get 200rwkw by running 25psi on 8.0:1 compression
or by running, say, 17psi on 9.0:1 compression. Which one will be more economical?

[RONA]

lets just say you could get 200rwkw by running 25psi on 8.0:1 compression
or by running, say, 17psi on 9.0:1 compression. Which one will be more economical?

It depends how they are tuned , the 17psi might have fuel thrown in it up the kazoo to stop it detonating just playing hypotheticals here. 9:1 still isn't a high comp setup though

[Ben Wilson]

Higher compression will probably use less fuel off boost, on boost, economy isn't an option

[adamaw11]

ok, fair enough. so at the end of the day, all things being equal apart from compression and boost, making 200rwkw will require exactly 200rwkw worth of fuel yes?

9:1 still isn't a high comp setup though

yeah, I hear that a lot of late model factory turboed things have 9.5 ish static comp to start with


(sorry for the thread hijack btw)