Long block vs. Short block

[Scatman]

Next topic of discussion: 1.8/1.9 8v vs 2.0 8v...
Which is more rev happy? Is a short block 2.0 better and why? I heard long blocks take long to rev up.

Obviously you have to take bore into account and the flywheel weight etc, but I've heard that the best combination is a 1.3 crank, some trick pistons and a 16v head to get to 10 000rpm. Apparently this is what's used in the berg cup motors?

[VWicked]

ok I am the kind of guy that beleives the no replacement for displacement arguement...

Yes 2.0 vs 1.8 is heavier but the longer stroke helps with torque which should help you pull stronger through the rev range.

Long block vs short, I have owned both and I feel that the long block makes more torque and seen proof on the dyno with my cars, now some have said that this is wrong so lets discuss...

[Torker]

I always had the understanding that the tall block motors is happier at high revs because of the better rod angle compared to the short block.

[VWicked]

look also if you plan to build a 2.0 shortblock then why not go wild and go big bore and so on, but at the cost i would plonk in an ady everytime and be done...

[Vinnige Fanie]

Damn I guess I cant leave my comment Scatman?

[joggiep]

Long block has a slightly better rod ratio that mean slightly less wear on the bearings but the bore - to - stroke ratio means more for the "revv caracteristics" of the motor a more square motor revs up better and a under square motor = more torque low down .. but then something like the S2000 is a "long block" hardly a lazy motor (Some of the highest piston speeds of motors out there).

Again I believe that it comes down to a combination of things rather than just one thing that makes the one revvy / torque .

[Torker]

Long block has a slightly better rod ratio that mean slightly less wear on the bearings but the bore - to - stroke ratio means more for the "revv caracteristics" of the motor a more square motor revs up better and a under square motor = more torque low down .. but then something like the S2000 is a "long block" hardly a lazy motor (Some of the highest piston speeds of motors out there).

Again I believe that it comes down to a combination of things rather than just one thing that makes the one revvy / torque .

When I pointed this out in another thread about 1.9 'strokers' I got shot down... ( http://www.vwclub.co.za/phpbb3/viewtopi ... ilit=+bore )

[VWicked]

Long block has a slightly better rod ratio that mean slightly less wear on the bearings but the bore - to - stroke ratio means more for the "revv caracteristics" of the motor a more square motor revs up better and a under square motor = more torque low down .. but then something like the S2000 is a "long block" hardly a lazy motor (Some of the highest piston speeds of motors out there).

Again I believe that it comes down to a combination of things rather than just one thing that makes the one revvy / torque .

When I pointed this out in another thread about 1.9 'strokers' I got shot down...

the 1.9 team and tough my bru... I am a 2.0 man, and if i ever need to rebuild my cti motor i will go with just bigger bore pistons 83.5mm and 298 Its just that 2.0 cranks are so rare now days

[Scatman]

Damn I guess I cant leave my comment Scatman?

Why?

[Dirty Harry]

I'm not too sure what it relates to but there is less 'dwell time' I think its called...the time from when the piston gets to tdc and then starts going down again...

Short block I have heard that a 2l, the rod and crank angle will eventually cause trouble.

Oh yes....please explain a 'stroker motor' or stroker kit?

[Scatman]

I'm not too sure what it relates to but there is less 'dwell time' I think its called...the time from when the piston gets to tdc and then starts going down again...

Short block I have heard that a 2l, the rod and crank angle will eventually cause trouble.

Oh yes....please explain a 'stroker motor' or stroker kit?

Basically you take a short block with a bore of 82.5mm and whack a 1.8 crank in there with some 2.6 Kombi pistons or some modified BMW pistons and viola, you have a 1973cc motor or something to that effect

[Naku786]

I'm not too sure what it relates to but there is less 'dwell time' I think its called...the time from when the piston gets to tdc and then starts going down again...

Short block I have heard that a 2l, the rod and crank angle will eventually cause trouble.

Oh yes....please explain a 'stroker motor' or stroker kit?

+1

[VWicked]

stroker, kombi 2.5 oversize 83.5mm and 1.8 crank.. 1893 cc motor the infamous 1.9

[G-spot]

For some reason I always preferred the 1.8 motors to the 2.0 long blocks. Ive heard that the small blocks rev up quicker, Could be because of the shorter stroke. But i cant imagine it to be by much. Longer stroke would make more low down torque, But also, Cant imagine it to be much.

I will own a 1.8 16v on throttles one day. it will take a lot to convince me a abf is better.

[Scatman]

VWicked is probably more clued up on it, but I think you get the picture

These motors make about 105Hp atw at Panic and around 148Nm.

[Dirty Harry]

From my understanding a stroker is a motor where the stroke is greater than the bore....in which case all vw(most) are strokers yes?

I still want to build a strong 1.9,2.1 8v...just for kick sake. And then a mild-ish 16v...

2.1 long block and 1.9 short block...sorry for the off topic-ness

[Scatman]

The rev-happiness of a motor is also largely determined by the head. A better flowing head will obviously rev much more freely as it would be less restrictive. Basically the shorter your stroke, the less torque you make. And since power is a function of torque x rpm, an engine with low torque can make big Hp if you rev it sky high (like an F1 engine). Conversely, you get motors with long strokes and smallish pistons that rev very slowly but make loads of torque (think a Lister motor on a farm etc).

Capacity also plays a role, but to me it would seem that capacity for capacity a motor with a longer stroke will make more torque than a short-stroke motor, and a motor with a longer stroke won't be as willing to rev up as a shorter-stroke motor due to the rotational mass which increases the inertia etc.

[Vinnige Fanie]

Damn I guess I cant leave my comment Scatman?

Why?

This long block nonsense is dumb mine revs pretty fast :tosser:

[VWicked]

For some reason I always preferred the 1.8 motors to the 2.0 long blocks. Ive heard that the small blocks rev up quicker, Could be because of the shorter stroke. But i cant imagine it to be by much. Longer stroke would make more low down torque, But also, Cant imagine it to be much.

I will own a 1.8 16v on throttles one day. it will take a lot to convince me a abf is better.

No doubt the 1.8 16v revs like mad, but the problem is what you have 'heard'. I still think you need to drive both in the same size vehicle to know the difference.

[panic-mechanic]

Ok before we even begin to discuss anything further. When you okes that talk about the revability or revving up or free revving talk about it what exactly do you mean. Do you mean the way it revs when you want to impress your friends. ie. when the engine is free of load and you blip it or the way it performs on the road or where it is rev limited?.

[joggiep]

My understanding is how quickly a motor would rev thru the rpm range under load.
Ie. My CTI used to rev quite quickly from any rpm thru to the limiter, the caddy in comparison makes mutch more power but feels slower thru the rpm range esp. at the higher rpm range.

[Jet Li]

For some reason I always preferred the 1.8 motors to the 2.0 long blocks. Ive heard that the small blocks rev up quicker, Could be because of the shorter stroke. But i cant imagine it to be by much. Longer stroke would make more low down torque, But also, Cant imagine it to be much.

I will own a 1.8 16v on throttles one day. it will take a lot to convince me a abf is better.

No doubt the 1.8 16v revs like mad, but the problem is what you have 'heard'. I still think you need to drive both in the same size vehicle to know the difference.

MK1/Velocitis excluded. Those things are supper light, they fly with a stock 2.0 8v. I think MK2/3 golf setup is fair to test engine perfomance.

[Abnormal]

A stroker motor is generally one in which you have increased the stroke. Nothing to do with the stock stroke

[panic-mechanic]

Ok how quickly an engine revs installed in a car under load depends on a snot load of things. IE. weight of the vehicle, gear ratios, HP made, torque at what rpm etc.etc.etc. It's a subject that can be discussed ad infinitum but it comes down to inertia at the end of the day. The lighter componets are in the whole setup and the more hp you make the faster it will spin up. So a big hp light motor will certainly spin up faster than a small hp heavy setup. the actual bore and stroke has very little to do with it except to say that there is no replacement for displacement.
Honestly a guy that says he 'prefers' a smaller capacity motor that feels fast has not driven or experienced a decent hp bigger capacity motor that makes more hp and that is installed in something light. Long block or shortblockhas really very little to do with it. It's rotating mass vs breathing ability. So make it light and make it breathe well.
But honestly. lot of it is personal experience and so forth so you build what you like and leave it at that. As long as you enjoy what you have who cares.

[ACiD_Omega]

Thread Ender of note!