Dump Valve

[Deano]

900bhp

[Unity Jon]

just because you cant hear them doesnt mean they're not there.....

all factory fitted turbos run a valve or compensator of some sort or another, if they didn't (as Rick has already stated) it will blow thing apart, thats why really old cars that had turbos always had trouble and proved unreliable

Kharma are you sure you've plumbed yours correctly ?

[Karma Supra]

lol Most cars do.. theres a guy in guildford that thinks hes well cool because he's taken the DV off his impreza.... we give his turbo about a week...

I am positive I have plumbed mine in correctly.. its not that complicated.. and I'm fairly confident with basic mechanics ;)

I do know about turbine stalling and blade stress.. I'm juts saying I have observed many cars wthout a DV.

I will fit a recirc to my car, but in the mean time I will restore the set up back to standard.... I think the reason some of the serious power cars don't have them is because at very high boost levels most BOV's leak boost... if the car is built for race use only chances are it'll get pulled apart and rebuilt at the end of the race anyway!!!!

[Karma Supra]

all factory fitted turbos run a valve or compensator of some sort or another

sorry mate I'm not arguing for the point of arguing.. but that is simply not true. I'm almost posetive my car doesn't (and very suprised to find so!). escort RS turbos never did, nor fiesta turbos....

[VTRick]

there must be some kind of built in valve somewhere, it could be a recirc built into a pipe that you cant see, but there must be some sort of pressure release somewhere. do you have a boost gauge? coz it would read constant boost if it wasnt letting the boost out somewhere.

[Karma Supra]

Like you say the boost runs out thru the turbines. it does this as std. when I floor it again after a gearchange I have to build up boost again. No offence mate but have you ever driven a 1G-GTE supra? I know the car pretty well now as I've had since march.. and I'm used to it.,.. learnign more about it all the time.. its like NO uk engine at all. just plain odd :P

Don't get me wrong I WANT some for of preasure release... fitting the atmospheric one has made a huge difference in spool up time...... its juts totally baffled the ECU and on this car runs worse then not having one at all.... Odd? I know. I have had 2 other twin turbo cars and built from scratch a 3.0t supra.. they all ran fine with one.. and they all came with one as std (recirc).... this is just an oddball.... thats why its so rare and thats why I like it ;) the turbos are so small and the boost so low.. as std its fine without... well it managed the last 15 years ok ;)

The Route I'm going down is to fit a std Saab BOV, taking the boost from the inlet manifold and dumping it between the turbos and the AFM.. this way the preasure is disapated.. the turbines are inder less stress and keep spinning.... and the ECU will be happy....... I'll even not have that 4 million decibel asmatic wheezing my car currently emits :P

[Scot]

My old man has just put 4 washers either side of the wastegate on his 7MG-TE and has halved the turbo lag!!!!!!! and upted pressure from 5psi to about 7.5 all this for £3.50 :D :D :D

[Karma Supra]

thatsa popular MA-70 trick :D works well... to do it on mine I have to do it twice.. and get it spot on... of one turbo blows harder then the other *snigger* it all goes horribly worng!!!

[Scot]

thatsa popular MA-70 trick :D works well... to do it on mine I have to do it twice.. and get it spot on... of one turbo blows harder then the other *snigger* it all goes horribly worng!!!

ahhh :D

[VTRick]

alright alright, i believe you, ive argued my point loads but i give up. lol.

its just <I thought I could get past the swearing filter - what a sad muppet I am eh?>in wierd. your turbos must chatter like ***** when you let the throttle up. it just seems wierd not to have one.

[Unity Jon]

taking the boost from the inlet manifold and dumping it between the turbos and the AFM

???? is this a typo ? the boost needs to come from the exhaust manifold that's why when you take your foot off the accelerator the engine slows producing less exhaust gass and less boost and doesnt OVER FUEL the intake !

if you allow the boost to enter BETWEEN the turbos the first one will not get any and wont spin up fast enough to allow flow through to the second one, where as the second one will be flying this will also need erratic fuelling to run properly. You'd be better off with only One turbo plumbed correctly, the first one is just a blockage !

[Monster-Mat]

agree with some comments, there really is no point fitting a dump valve unless you have the tuning to require it, most turbo engines do not generate the boost to cause damage to the turbo when letting of the gas, a highly tuned engine produces the compression to destroy the blades of the impeller, this is where the BOV comes into its forte, other than that its a show piece...and sounds either good or bad depending on tast.

The tomcat engine is a T series Rover engine, based on the old Maestro block....Princess block before that

the honda engines are the 2.5 V and the 1.6 engines

[Unity Jon]

The tomcat engine is a T series Rover engine, based on the old Maestro block....Princess block before that

the honda engines are the 2.5 V and the 1.6 engines

a little more too it than that......

the 2ltr turbo engine thats found only in the Tomcat is a Rover engine thats been re-engineered by honda, thats why it has Honda Part no's stamped all over it.

The N/A coupe (not a tomacat !) engines are definately the old Rover lumps and the 414/416 run the K-series engine.

[Monster-Mat]

i know the rover engines well, i raced the 216 gti for 3 years.

i was refering to the old series engines being honda not the current 1.6 models.

only the head was engineered by honda for the T series, the actual development was done at Tickford engineering

but this is going off topic...sorry

[Deano]

i think i will only get one if i get offered one on the cheap :D

[Unity Jon]

s'ok i was talking about the current 2.0 turbo..... the others didn't have BOV or turbo LOL.....

[Karma Supra]

it was not a typo. between the turboS (as a pair) and the afm.. i.e. the two turbos ... see them as one unit.. between that unit and the AFM.

VTRick.. yup its weird!!! took me a while to accept too!!!!!

superchargedIS200: here here!!! we are taking 5.5 psi boost per turbo here!!!!! hardly inlet popping quantaties ;)

[Karma Supra]

incidently.. for anyone that doubts me.. next time we have a meet feel free to have a nose around my engine bay!!!! In your shoes I'd probably not beleive either ;) looks like I'm at brighton this sunday with the chap in the WIDE gold supra and (kerry???) in the balck mk3 surpra turbo... and I'll defo be at santa pod on the 12th.

If anyonr can prove me wrong I'd be gratefull as it'd be a new big of knowledge about this odball engine that I run!!!! (you try tuning an engine that no sod knows anything about! LMAO)

aparently there is one in aus running 500 pomies on stock internals :o garret T4 and 12 injectors LOL... lets see if its aroufd this time next month LOL

[VTRick]

now running a t4 he definatly has a bov!

if not, then no, it wont be about next month. lol