Anonymous

Westy, presure and flow are related mate.

Get a mcdonalds straw, put your finger over the end and blow on the fooker.

you will notice that its now as hard as a paedophiles cock in a playground yeah?

Now take your finger off the end and try and do the same thing!

Now try squeezing it so its only a tiny hole in the end leaking out and you can make it hard again, then as you loosen your grip and more flows its harder to maintain the pressure.


Thats the same as increasing the VE of an engine mate.

Westy

iTrader: (1)

Chip - figures aside.. Im merely pointing out that a turbo is capable of 17psi... I personally cant see how 258 is achieved at 17psi.. (unless serious mods etc have been done)

I gotta go, as i can see this being technical soon.. way out of my league

Westy

iTrader: (1)

this is the bit that i have trouble understanding.. at 17psi.. which isnt much.. how does this over speed it?? or is this the McDonalds thing your on about

im genuinely interested

Ginge !

westy 17psi is presure not the air flowing !!!!, 17psi in a straw and aim it at a house

17psi in a 40foot diameter tube and aim it at the house, bet the house falls down

Westy

iTrader: (1)

b19bal.. that makes it clearer for me.. cheers mate

Westy

iTrader: (1)

just a quick one..

a small turbo producing 17psi makes less power than a large turbo running 17psi.. correct

Ginge !

yeah as its flowing less air, unless ya raise the comp ratio of the engine

OR if ya add too big a turbo and get it surging its pants off

swanny

/me goes for a shower before my head pops

Ginge !

nice looking motor btw

Anonymous

Airflow is the key thing NOT boost.

For every lb of air you can shift per minute you will make about 10 or 11 horsepower roughly on a properly setup engine.

Simple as that.



Pressure is a result of how much air the turbo is trying to flow versus how much air the engine can consume, in essence the amount of boost is actually as much a sign of how badly the engine is designed as to how good the turbo is.

Hence skyline motors make stupid power at moderate boost levels, because despite the turbo throwing loads of air towards the engine you never end up with much in the manifild because the engine happily consumes it all.

An R5GTT is the opposite, tiny little turbo barely flowing any air but the engine is such shite that you still end up with 2 bar in the manifold very easily.




For a simple analogy.

A barmaid is racking up drinks on the bar, while you down them.

The number of drinks on the bar (the boost pressure) is a combination of both her ability to pour them out (the turbo) and your ability to drink the fookers (the engine)

Ginge !

chip do ya think of anything else but women and beer

Ginge !

and i need a place to park the car too, i got a shite hot parking space at the moment but no place to remove the engine

Fudgey

iTrader: (4)

i love the way chip explains things!!

louma84

back to the original question yes the bottom end can handle 200bhp as long as its good condition! not 90k+. alot of rst's are blowing up coz of det ie people using bleed valves and not getting them properly set up etc. how long can you expect a rst to last if your running 200bhp through a 90k+ bottom end??? . get a rebuild with proper bolts, rebore, good pistons, decent headgasket and bolts and then it will run 200bhp all day as long as its set up correctly

rswoza

my old s1 had 120000 miles ran 17 psi and ran 188 bhp for 2 years no probs what so ever. was set up every 6 months

my new s1 is running 186 bhp 10 psi and done 9000 miles on new engine with very basic mods and basic rebuild.

both ran bleed valves managed 14.4 at santa pod as well in the old s1

Ginge !

bad advice there matey, the best headgasket for a cvh is a standard ford aswell as the bolts too

arp rodbolts thought at the right torque setting

DanRSturbo

How is getting a decenct headgasket bad advice ? He didn't name a brand did he ? Or did I miss that

Tim

iTrader: (1)

This was my first engine with a cossie 4x4 turbo flat out,
As you can see the boost dropped to 20 ish psi as it could not produce enough flow to keep the boost up.
Car had loads of mods to produce this,should have gone to Jamsport lol

Keith B

Rick - the 175k S2 that you 'have' under your wing. That wouldnt be my old S2 now owned by James & Linsay would it?
If so then, dude - it got to that mileage with lots of care from myself and Power Engineering and very little else.

GrimmeRS2K

i couldnt even get 200bhp out of mine the other week, my bottom end is standard apart from ross low comp forged pistons, and a 1mm overbore, my head(standard) let me down as it couldnt eat up the air and my power dropped off at only 4k!.

but they did have a problem with it staying on the rollers though

Steven_RW

power dropped off at 4k?

on a std head?

4k?

hmm sounds a little low to me

RW

louma84

there are plenty of good head gaskets and head bolts out there that are better than the standard ford ones!

james_birch

MAYBE but.....

nearly everyone i spk to is runiing std ford stuff........can only think of one reason why!

Tim

iTrader: (1)

Such as ? being that the ford is a metal gasket .
Felpro is cardboard,payne is ford anyways,what else?

louma84

cometic gaskets 4 one .
hava look www.cometic.com

Tim

iTrader: (1)

After the last effort we wont be using 1 of them lol

essexrsturbo

you are possibly the wrongest person on this post

Ginge !

tell me what power is the max YOU have seen with a cometic as i have seen a few 280 to as much as 314bhp cvh engine erst's using standard ford gaskets

also using standard headbolts too

so if ya saying a 230bhp erst used a cometic and its working perfect i would hope so as ford gaskets are used in the high power cvh engines

ford gaskets do fail when fitted my monkeys though who tighten up the gaskets too quick, ya need to give a few mins between tweeks

louma84

im not saying that ford gaskets can take this or that amount of bhp. at the end of the day its up to people wot gaskets they use , but i know that if i was running 314bhp through a cvh i would want a gasket that was of the finest quality and material. ford designed the cvh rst with 130ish bhp not 314! and don't fink they designed the standard head gasket to run that all day! its not economic!

GrimmeRS2K

i think as said above, its mostly about the fitting of a headgasket makes all the difference,

when rebuilding mine, i used only ford gaskets, including the headgasket, when ordering from burton power they advised me to fit the ford one,as the felpro one had some problems, also alot of other tuners advised on the ford one,

AndyRST

A RST std bottom end will take 18psi provided the fueling is set-up correct and the air cooling is good enough. A std RST bottom end can only be reved to 6200rpm safely before needing ARP bolts or steel rods. Its best to get the engine checked ever 6 months on the rolling road when running this sort of power.

"IF" the engine is in good condition @ around 18psi held on the std T3 you could see around 220 bhp, if the engine a bit tired you are more looking at 180-200bhp max but if it is a tired engine then its not wise to run it at 18psi 15/16psi would be safer.

Mine has made 200+ bhp for the last 4 yrs now and is just over the 100k miles mark, i have to admit it doesnt feel as fresh as it did when i 1st bought the car but it still makes good power.

HTH