ea82t & ea82 differences.

waggaclint · Post by **waggaclint** » Sun Jun 18, 2006 4:55 pm

what are the differences between theses motors i no heads and manifolds etc and compression pistons etc but are the blocks and crank,rods etc different as well can you bolt all the ea82t stuff onto ea82 block.

schultzie · Post by **schultzie** » Sun Jun 18, 2006 6:12 pm

i beleieve the only difference in the heads is that the turbo heads have an oil line for the turbo... i could be wrong

steptoe · Post by **steptoe** » Sun Jun 18, 2006 6:27 pm

and that efi heads on turbo motor have twin ports from looking at it and carby heads don't. Carby manifold might be impossible to bolt to turbo or efi heads.
Raises a good question

are EA82T heads and the mpfi heads the same or share same gaskets etc ?

Gannon · Post by **Gannon** » Sun Jun 18, 2006 6:45 pm

Mpfi and Turbo heads are the same, and interestingly, there is no difference between left and right heads,... except that the turbo head has an oil feed and return and a coolant feed.

Turbo pistons are 7.7:1 compression, NA pistons are about 9.5:1

There are no differences between the blocks, except the mpfi and turbo ones have an extra pcv port behind the flywheel, but all are still interchangable.

There is no known difference between the NA and turbo internals.. ie. crank, rods ect

There is an advantage to putting turbo stuff on a NA block, higher compression before boost, and thus more low rpm grunt.
There are quite a few people from the US that are doin this.
Im tempted to do it myself

There are no real downsides as long as you run good quality fuel.

Gannon

schultzie · Post by **schultzie** » Sun Jun 18, 2006 7:40 pm

There is no known difference between the NA and turbo internals.. ie. crank, rods ect

how does the compression ratio change then, or is it in the pistons?

is optimax concidered quality fuel?

you wouldnt be able to run as much boost with that sort of compression with out risk of doing damage would you?

waggaclint · Post by **waggaclint** » Sun Jun 18, 2006 8:51 pm

as long as its not running lean or pinging it wont hurt it if its tuned right there wont be a problem. i reckon i would use an aftermarket ecu but you can tune em heaps better.

Gannon · Post by **Gannon** » Sun Jun 18, 2006 9:08 pm

Suparoo wrote: Turbo pistons are 7.7:1 compression, NA pistons are about 9.5:1

There is no known difference between the NA and turbo internals.. ie. crank, rods ect

Gannon

Sorry, i should have made it clearer

I meant that there are no known structural differences between the turbo and NA block and internals.
Turbo pistons have a larger hole in the top

The higher compession doesnt make all that much difference under boost, somebody on the usmb worked it out, it was equivilent to running a little less 10psi

waggaclint · Post by **waggaclint** » Sun Jun 18, 2006 9:15 pm

thats right really the way it works is boost is like upping your compression the more boost the more compression there is.

waggaclint · Post by **waggaclint** » Sun Jun 18, 2006 9:16 pm

that why when you run high boost you need better pistons and rods because theres more pressure on them and standard ones will fail.

damo666 · Post by **damo666** » Sun Jun 18, 2006 10:23 pm

I'm very tempted to build a 9.5:1 comp turbo motor for the rallycar, it would make off boost & on/off throttle changes really responsive (not that the standard turbo really takes too long to wind up!). I think an aftermarket ECU is a must with this setup though.

I had an old VL Commo that ran the turbo bits on an N/A bottom end, and it was fantastic to drive. Just as quick at 7psi as a friends 'proper' VL turbo at 12psi.

Would be interesting to see how a 9.5:1 motor & TD04 turbo woulg go together....

subanator · Post by **subanator** » Mon Jun 19, 2006 12:10 am

No one has mentioned the cam?? I would expect the turbo one to be different, as overlap and lift would be different (yes mild) compared to n/a.

Gannon · Post by **Gannon** » Mon Jun 19, 2006 6:47 pm

Yes subanator, your right, the cams are different
I read a detailed explanation somewhere once but i cant remember how they are different, but in know it had something to do with pulse timing and extraction that is needed on NA models to help scavanging of exhaust

mAJORD · Post by **mAJORD** » Mon Jul 10, 2006 7:41 pm

EA82T head gaskets are different. (differnet material i belive)

I think also, the piston to bore (or something along those lines) Tolerences are tighter, when reading through the engine rebuild data.

subanator · Post by **subanator** » Thu Jul 13, 2006 12:52 am

Does anyone know if there is a difference between the N/A to turbo injectors and resistors etc, as my tuning reveiled it was running lean. This has now been solved by other means, but may still be an issue as it it was converted and left the original resistor bank on the strut tower?

wagonist · Post by **wagonist** » Wed Jul 19, 2006 12:18 pm

Suparoo wrote: Turbo pistons are 7.7:1 compression, NA pistons are about 9.5:1
There is an advantage to putting turbo stuff on a NA block, higher compression before boost, and thus more low rpm grunt.
There are quite a few people from the US that are doin this.
Im tempted to do it myself

There are no real downsides as long as you run good quality fuel.

Gannon

Don't you mean put NA stuff in a turbo block?
turbo stuff in an NA motor would give 7.7:1 compression.

Smokey · Post by **Smokey** » Wed Jul 19, 2006 5:59 pm

wagonist - I think Suparoo meant, use an NA block with NA pistons and then bolt on the turbo, giving much higher compression before any boost is added.

Don't you mean put NA stuff in a turbo block?
turbo stuff in an NA motor would give 7.7:1 compression.

Smokey

wagonist · Post by **wagonist** » Wed Jul 19, 2006 7:11 pm

It had to be somehting different to what he posted. I just wanted to point out politely that there was an error.

subanator · Post by **subanator** » Sat Jul 22, 2006 11:39 pm

Thanks to Suby Wan Kenobi, he posted a reply to me as:

Turbo injectors have a red ring on the base of them and NA ones are grey

as there is a difference in flow between them.

Gannon · Post by **Gannon** » Sun Jul 23, 2006 7:39 am

Smokey wrote:wagonist - I think Suparoo meant, use an NA block with NA pistons and then bolt on the turbo, giving much higher compression before any boost is added.

Smokey

Thanks Smokey, yeah thats what i meant.
A NA block has a compression ratio of about 9.5:1, the turbo block has a ratio of 7.7:1 (the difference is in the dip in the top of the turbo pistons)

There is no difference between turbo and NA heads as far as compression goes. Just the cams and the oil/water ports.

If you take a NA block with 9.5:1 comp, and add turbo heads and a turbo, it gives an engine with much better off boost grunt.

Im hopefully (touch wood)

doing this very soon, but probably going slightly less than 9.5:1

Sorry if it has been a bit longwinded, i just wanted to eliminate any further confusion.

Gannon

steptoe · Post by **steptoe** » Sun Jul 23, 2006 12:17 pm

in addition to the comment re turbo block has a PCV outlet rhs block at the rear top side - to go with this is a chamber in the back of the rhs block with a cover plate and cork gasket. The NA block I have does not have the plate.

Some sort of fume separation chamber ?