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Low compression block for non turbo application

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What can I expect if I will fit low compression 8,5:1 block to my car and will be driving without turbo or supercharger. Just N/A engine with some well speced head, cams and maybe VSR manifold.

 

I'm planing to fully rebuild my Corrado and have already brand new short block for turbo application with 83mm pistons and 8,5:1 compression but how car will be driving without turbo. Will be slower with lower compression or what ??

 

Faster or later (probably later this time) I will fit turbo so its good idea to fit this block and drive so far as N/A application but how it will be driving ??

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Yeah im guessing it will feel gutless compared to standard compression, you could run it with some nitrous to compensate in the mean time? :)

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Early range/land rovers were 8:5-1

Will have less power,but you will be able to run it on cheap unleaded.

 

Cheap unlead. Doe's something like that exist ?? :D I'm usually driving on 95 unlead anyway.

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When my 8.5:1 compression engine was first dynoed without the spring in the wastegate to get it running sweetly before mapping with the turbo, it produced 148bhp.....

So yeah, a low comp engine will definitely produce less power but depending on how long you intend to run around without it being FI and how much you use the car, I'd say it would be ok. Just don't try and take anyone on at the traffic lights!!

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That's because all 3 litres of exhaust gas is going through a small wastegate hole.

 

An 8.5:1 engine with no turbo and the proper VR6 downpipes and exhaust, will make more power than that.

Edited by Kevin Bacon

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My 9:1 felt barely any different to stock. Standard 10:1 is hardly blowing anyone's skirt up though, especially with the silly tall standard final drive :lol:

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Gutless was a bit strong, it's just when you give it some it's just not all there at 4K rpm +. For normal driving its not noticeable.

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That's because all 3 litres of exhaust gas is going through a small wastegate hole.

 

An 8.5:1 engine with no turbo and the proper VR6 downpipes and exhaust, will make more power than that.

 

Yep. My 2.9 low comp lump running wossners was pushing out 221bhp / 204ft lb.

 

Schrick vgi, stock cams, schrick bvh, bmc CDA, raceland manifold + remap.

 

It didn't seem gutless, power was there on demand but I did have g60 final drive fitted too!

 

Shame I wrote it off before I got chance boost it.

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Proof is in the pudding.. So here's a video of a standing start at the nurburgring

 

 

The black VR is schricked up running around 210bhp... :)

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It didn't seem gutless, power was there on demand but I did have g60 final drive fitted too!

 

Good man :)

 

Such a great mod that, with or without boost!

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There wasn't much that car wouldn't chew up on the road and track.. was even faster in the mk2 shell!

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Good man :)

 

Such a great mod that, with or without boost!

 

Just bought a new fully reconed box with g60 final drive too ;)

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Yeah I keep getting tempted to get another MK2 and transfer all the rude stuff over :) A 200Kg weight saving would be like turning the boost up a few notches!

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Nice one, now I know which direction I'm going. Will save my block, then look for some performance head for turbo, put everything together, fit inside a car and drive a bit and then when finally turbo time will came I will be ready :)

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Strange as I was thinking about if i could do this as well if I needed to in the future. Would I need to change out to the standard ECU?

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You will need :

 

Standard ECU chip

Standard injectors

Standard Lambda

Standard MAF

Standard fuel reg

 

I ran mine standard OBD2, low comp, Schimmel intake & 3.68 Diff and it was bloody good fun. Still quicker than a standard VR6, but sounded nothing like a VR6. VERY loud induction roar. Didn't even sound like a 6 cyl, or a 5, or a 4. Very strange.

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You will need :

 

Standard ECU chip

Standard injectors

Standard Lambda

Standard MAF

Standard fuel reg

 

I ran mine standard OBD2, low comp, Schimmel intake & 3.68 Diff and it was bloody good fun. Still quicker than a standard VR6, but sounded nothing like a VR6. VERY loud induction roar. Didn't even sound like a 6 cyl, or a 5, or a 4. Very strange.

 

I was thinking about the implications of running a schimmel or similar inlet mani with standard management, if the same throttle body is used do you avoid any issues? Was it easier for you because you are running obd2?

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