What is the ideal spec for a GT30 engine?

• Block
• Pistons
• C/R
• Cams

I'm in the early stages of souring the build parts, so far i have the bigger parts inc a GT3076r internally gated turbo, new 10 stud 200 block, Cosworth racing pistons 7:2:1

(as the 500bhp thread in the Tech Essay section explains C/R in detail is it better to use pocketed standard piston over a lowered compression piston?)

What i would also like to know is what spec Camshaft and configuration were people advised to work perfectly for the GT30 turbo?

 

Think Mark Shead at madevelopments has done std comp,gt30 conversions with autronic and vipec to good affect.

Best to get advice from someone who has actually done it correctly and to good affect enabling you to save money in the long run.

Think his 500/500 conversions are based on the above

 

i would have thought a bd14 inlet and standard exhaust would be best, to take advantage of extra airflow at top of range from the gt30.

 

My spec, but for a 3071

200 block - 6 long studs
Custom CP Pistons to Mark's spec
8:1
Slightly ported head
Double valve springs
Mark's inlet cam, std exhaust cam
Can sun std inlet with spacer but i'm looking at a hart inlet (group buy coming soon)

Think that's about it but probably missed a few bits...

 

ported head too is a must i would say Chris.

 

I have a worked on head 25/26 ports and polished - inlet is a 4x4 with a Reyland 17.6mm spacer which throws loads of air in.

I have read that EP have one about to tested that is due to match the MAD item so i might give that a go.

But what do people think about C/R?????

 

Yes you would definately need some kind of porting for a 3076

 

I wouldn't go as low as 7.2 on Cr, I think 99% of tuners try and stay around 8-1 now.
Gone are the old days of having to run low comp for big boost safety.
And judging by Cossie richs gains when he used a mad inlet over a bd14 I would go with that,
And definitely a hart inlet, not only does it increase flow and allow more power but it give a more even distribution of air across all 4 cylinders.

 

I agree with Stu above,in the old days lower comp was favoured,nowadays most tuners will tell you to stay around standard comp with valve cut outs(depending on cam choice of course).
Chris speak to your chosen tuner m8,they should give u the info u require.

Thanks.Lee.

 

Mark will only sell you an inlet cam if you're having an engine built by him

 

James I had also heard that, the reason I'm waiting to see what Danny gets out of there's.

Lee I will be speaking to the tuner soon but I think valve cutouts in standards is the way I may go, I think Harvey does it ???

 

gotta be best not to skimp on pistons.

I heard CP are the best, i bought wossner once to save money.

Lets not talk about how that turned out

 

My cam works for sure but im going to show everyone how well soon as im doing a std build just valve cut outs and a 3071 spacer on inlet and 83lbers and bench dynoed to prove ..
Will also book with harvey to do back to back on hes dyno even though its the same as harveys just to shut the doubters up....

Iv already seen 452hp and 440lb ft on my cam and that was at a 2 bar peak 1.9 bar held engine with very similar spec as above so it deffo works...

As for cr brammer just go cosworth or cp with std crown and then get cut outs machined and with a good deck head you will be circa 7.7-7.8cr wich will be spot on..
Any info or help and all you have to do is ask mate...


cheers danny

 

Danny are you going to be around Silverstone tomorrow????

 

Yes mate come and say hello and we can chat about your engine etc...


cheers danny

 

not true, i rang him for a price and told him what i had in the engine, he said i could buy and fit it but he wanted to time it and it would need a live map, preferably by himself ofcourse.

if danny offers a good substitue then no reason not to buy from him instead.

 

I spoke to a few top tuners about c/r when i built my engine and most said lower than standard is better. I think ther's only mad that like standard c/r. 1 said if u have your car flat out for a long period standard comp will det.

 

Its more than just a inlet cam and its hard to prove its is a match but its easy to say it is

Mark

 

OK.

 

Mine is 7.5 c/r bd 16 inlet bd14 exh

Potted head, st inlet, etc

 

The whole engine as a package will be tested and the inlet cam will be the biggest change apart from the air pump and injectors and with brammers spec my cam will be awesome..


cheers danny

 

Danny this cam is a new unit i take it?? do you have any rough info to when it will be available from and price - pm if you prefer.