Franco,
An externally gated turbo adds a MINIMUM of £600 on to the cost of installation (wastegate pipe, spacer plate and wastegate) - that's doing it on the cheap. Once you get to the flow limit of the 2wd manifold, then that cost jumps to £1,500ish (with a tubular manifold and external wastegate) .

To be honest, apart from for down the pub - when is 500bhp NOT enough for a road car? . With the new generation of FULL ceramic roller bearing cored T4s - WHY would you want to use anything else to achieve 500-550bhp?

Obviously I have no experience of an integrally gated GT30, but speaking to Vince, he never rated the early versions of this, so I have always stayed away from them. However, like everything - technology moves on, and it wouldn't surprise me to learn that this has now been perfected thanks to constant R&D, but again I haven't seen it tested back to back with the latest generation T4s to see if it offers any improvement over these. Whilst something delivers EXACTLY what I want, I stick with that - for fear of being a turbo manufacturer's guinea-pig / free test-bed .

 

Read you emails!

 

He cant, he's too busy doing political broadcasts on behalf of the Truck Turbo party.......

 

Franco,
Give me fucking chance you queer .

 

L8 ECU


Mike Rainbird
You'd love me to be queer.............Then you wouldnt have to try so hard to fuck me!

 

Jay,
I didn't realise telling you to "fuck-off" was considered fore-play .

 

It is where i come from!! I'm aways getting told this in nightclubs!

Anyway back on topic!!!

 

Jay how about using the old hairdyrer you used to have for your luscious locks.. that would have needed some power!

 

Mike, excuse my ignorance, so where you say pick your turbo and build your engine around that, what happens when you have a engine built by JOE BLOGGS ,you pretty much know the spec, but then you go to a different mapper/builder for a certain turbo choice is it going to be just guess wotk with what spec turbo then?...

 

I'm going to hurt you....................!

 

I bought my Garret GT3082 from www.atpturbo.com, about 1100punds with heatshield and ultimate internal wastegate, think it will perform great!

 

Depends what the engine was built to achieve in the first place. If it was designed around being able to deal with a LOT more air at a later date (with suitable porting and cams), then bolting a bigger turbo on will get the benefit of the original engine spec (some people do do this due to budget constaints and build the engine in stages). However, the way I do it is to build the engine to flow ONLY the power that I want to achieve. I do this to try and keep the response as good as possible. Unfortunately, depending on the port sizes, this can limit you to a particular sized turbo, before you will run into surge issues.

Obviously it is crucial to discuss turbo choice with your engine builder, before buying any turbo. If memory serves me correctly, your engine was built to be able to take a T4 (BUT that needs to be verified), so if this is the case, you would benefit from fitting a bigger turbo, as your engine could deal with this. All that fitting a smaller turbo would result in is perhaps a small loss of response and torque due to the reduction in gas speed with the bigger ports and smaller turbo, than could be achieved with porting matched to the turbo.

 

Franco&Mike Rainbird GET A FUCKING ROOM!

Funny Cunt! that Cracked me up!

Anyway! i suppose thinking i could ask a Question on here and get a straight anser was wrong of me

I know that getting your tuner to spec your engine for what power you want Bla Bla..............

What i was trying to get here was some people who have tested diffrent turbos on diffrent spec engines and try to see what there results are

i know you say Harvey is at the forfront mike but has he really had the time to test every new turbo that is on the Market for 500/550hp? if so then thats fair enough i will keep my mouth shut and just and you can do me a 5000 word essay that you can either post up on here or send to me in a Pm Explaining every detail like you have to with everythink else i ask you about!

wouldnt it be nice for a turbo to make 550HP at a Safe amount of Boost that makes full boost at 2500rpm and holds its power untill 8000+rpm as that is what i want myturbo to do for my engine Maybe thats what i should of ask for in the first place

 

Apart from the full boost at low rpm point - this is my turbo's capabilities at 32psi .

The ONLY way to achieve your 2500rpm spool up, is with variable vane technology. At this moment in time, there is not a turbo on the market that will achieve what you want (if there was, it WOULD be on my car ) .

You can have everything you ask for bar this, as the full boost point is 3500rpm with my engine spec. Hope this helps.

 

Hate it when you do that

Ile just shut up then

and you turbo is just an old maram shfted T4 witha 60 trim isnt it? how much you selling them for again?

 

£2k for my turbo with Mar-M shaft. This is NOT needed though, UNLESS you really want ALS.

You could use just the normal ceramic roller-bearing version which is considerably cheaper (price on my website ), which "may" also offer a few hundred rpm spool up improvement over my standard bearing type core (waiting for Euan to confirm).

 

or sequentials

but variable vane for petrol must come to the aftermarket soon? how about if using different fuel to normal petrol? can you get lower combustion temperatures with E85 or something?

 

I seriously hope so . Diesel would be okay . No idea about the E85 what-so-ever?

 

I know Euans engine had no problems running big psi with a ported head with standard valves but what sort of gains would be seen with bigger valves ?
Mike from what you said above think i might need to start saving for a new gearbox and a T4 if the head work is going to make it flat and down on torque running a T38.

 

Thought Euan had the boost capped to combat surge?

 

that surprises me

it is very available in your neck of the woods and is known to have a higher RON than SUL. i'm genuinely surprised that you haven't looked into it as you have an ecu with multi map capability

 

I think alan had to cap it slightly but dont think it was anything too major(dont quote me on that). I know the head i have has similar porting work too Euans but bigger valves, so if i do go forthe same turbo as him later it would be good to compare the results.

 

All I know is that it hasn't got as high energy as normal fuel, so although higher ocatne, you use a lot more of it per specific output. I also don't know how hot it burns, and when reading about it on the Lotus, they said that certain mods had to be carried out to the engine to run the fuel, but did not reveal what these were. Accordingly prudence prevented me from trying it on my new engine .

 

Mike is correct unlike his als post
It is not wise for anyone to slagg off the to4e it was specced by cosworth for the rs500 at 500bhp and is there fore hard to better, you can spend a lot of time and money getting over excited with the latest tech spec only to be beaten by an old 1987 rs500 that cost a fraction to build .You cannot redesign the wheel they say.Mike is a living example of teccie spending
Do not run a 60 trim bently comp wheel on a to4e unless you have redisgned the rest of the engine surge city.
Remember big is not always best or better it is just bigger
size does matter
would you buy size 12 shoes to look bigger and better when you only have size 9 feet

 

But Tony, what other turbos were there for Garrett / Cosworth to choose back in 1985 / 86 ? AFAIK choice was VERY limited, the only available unit was a deisel turbo hybrid T series unit (we know it as the T4).....

So yes, it could'nt be slaged off back in the day, allthough the motoiring mags did pick up on the "lag city" response of the RS500

We DO have a choice of big turbos nowadays, which is nice

 

that's true, but if you're injectors are big enough that wouldn't be an issue

there are certain issues with corrosion of the fuel system etc that would mean changes on a mass production vehicle - don't know about a custom system like you have

the time of a new engine would have been the right time to change. you could have then optimised the c/r to suit and made any changes necessary

reading around on t'internet the combustion temperature is lower than normal petrol

 

but wasnt that on a standard 224bhp car?they will seem bad compared to a 500bhp engine helping it.


what is the problem with gt series then that makes people slate them?

 

doug you seem to have read something else into my posy that I didn't say.
Perhaps I should have added that there are many more modern turbo's available bla bla bla
You seem to have read into my post that the gt range is not as good as the to4e can't see that I wrote that in my post.
What my post was saying is that it is important to spec the turbo to the engine and engine to the turbo.Which is what the to4e was.(was is past tense)
Lag was indeed mention in the 80's on the to4e but do remember it was an homolagation special and was never a road car no lag issues on the race rs500 reving to 8300.
JCB for you doug lol
The lag on the road going rs500 was due to the exhaust flow restrictors fitted to the front pipe

 

224 bhp with a turbo well over specced I rest my case lol

 

thats what i thought.so people really cant bring that into the agruement as its not a fair comparison

 

my boost is not capped at all.

Surge is something that we want avoid at all costs.

A turbo that surges its tits off and maybe gains me 20 bhp top end power will not last long on my car before we fit either a smaller compressor or a bigger turbine.


A nice wide power band is what makes a good road engine IMO.

I have seen bigger GT type turbos against a T4 in various graphs and I would not swap for either of them.

 

Thing is, they (the motoring press) did'nt have a 500 BHP spec car to compare it to...........BUT they did have T3 turbo equiped Cossie's (original 3 DR) that they could compare it to, so yes in a back to back road test the impression they got was that the RS-500 was a poor road car due to the oversized turbo.

 

Like Mike & Euan said in a few more words, a good road car is all about area under the graph it's pointless having 550BHP if it only makes 280BHP @5000RPM then explodes for the last 2500RPM , it will be horrid to drive on the road, you would be FAR better off having 500BHP max and a nice curve all the way from 3000RPM

 

At last, someone that understands - and is not just a "number chaser" . It's funny the amount of "number chasers" that have come a cropper from making the wrong turbo choice .

 

Mike Rainbird
in my experience mike i have come across alot of"big bhp"cars that have fallen short against supposed lower bhp figured cars. i put this down many times to three things. 1.the owner is full of shit and blowing imaginary figures out is arse or 2.the car has a poorly put together car that has the wrong bits together or 3.a very badly set up car.

i'd be very happy with a corrctly set up high-ish power car that can perform right rather than a "it made 580bhp on the rollers but its got fueling or boost issues"car

 

Bigger Gt turbos are good if you plan on really revving the car, in race application etc where a T4 sized turbo would be out of puff.

My advice is have a look on the garret web site and take some time to look at the compressor maps.

Its easier if you can get someone to explain them to you but its possible with a bit of time to be able to understand them and it makes turbo choice a lot easier.