what can be done to a 7a engine?

[bernsaudi]

a stock 7a .............. can it be turbocharged, or is it down to head change etc?
cheers, bernie

[Tonks4x4]

It can be turbo'ed It has been done before. You are better off changing the inlet manifold to s2 though.

[K Simmonds]

You would be limited to about half a bar of boost unless the compression is lowered.

[mikeraz1]

I've been looking in to this for a while now and am planning to turbocharged my 7a. 034 motorsport quoted me $4000 for everything needed to turbocharged the 7a. Im hoping to get a list of parts needed and then shop around a bit.

Taken from the 034motorsport website:

Machining service for Audi 7A head to bring the water passages to 20v Turbo specification. Precision CNC machined, accurate to .0001", a direct bolt in for any Audi water manifold.

We use the 7A head for heavily turbocharged applications, mainly for the reason that the 7A heads are RARELY cracked between valve seats due to the lack of stress the heads have seen, by performing this machining procedure the head is brought to basically 3B specification.
.

Also as i've been told that the 7a rods and crank are the same as the 3b.

Hope this helps

Cheers

Mike

[Flat on my back]

.

Dropping the CR is easy with the right pistons...

Golf 2 GTI, Scirocco,
Corrado 1.8 Ltr. 16V Turbo

Wossner do a range of sizes from 81mm to 83.5mm.

[gedu]

Yeah, 7A heads see so much lower loads, that they rarely are cracked. To take a 7A head to turbo engine, I recommend at least fitting it with 20v turbo engine water manifold. Other thing that might bite you is Hall sensor location. Crank is same, rods are the same. Pistons differ, as 7A specs 10.3 compression. Cams you might also want to change, as stock 7A are a bit laggy for turbo operation. Go either assemble a "suitable" pair from stock Audi cams, or you can go ex Shrick Bearings differ also if I remember my ETKA right.

[bernsaudi]

hello, what can be done to.....

hello, what can be done to.....a 7a engine i just bought.....can it be turbocharged?

[gedu]

Ermmm, check your previous post...

[bernsaudi]

sorry, laptop didnt show me it had posted, durrr

[bernsaudi]

ahh, this is good....ive just ended up with a 3b or aby engine with a rod thrown out the side and a 7a engine that is happy, so i got to thinking that between the two decent engine can be made...and it sound like that is the case. will the parts from the later engine suffice to do the 7a up then, or should i find more bits to finish the job.
cheers, bernie

[gedu]

7A has different bore when compared to 3b/aby/aan/adu. So what you need is new pistons at least (for 82.5mm bore, and larger if going for oversizes).

[bernsaudi]

so if i swap the pistons out of my aby engine and put them into the 7a block, that will work?
does anyone happen to know the piston heights for the two engine types?
cheers, bernie

[stiglet]

No, the bore is bigger on the 7A, so any turbo pistons will not work. You will need custom pistons or con rods that allow the use of the 7a pistons with lower compression ratio.

[K Simmonds]

Could the 7A pistons not have the crowns machined to drop the CR?

[stiglet]

It's not a flat crown so I'm guessing that wouldn't be easy. Probably the same as just getting custom pistons no?