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Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 5:56 am
by marcdh
I have had both manifolds on my kl31 cammed ZE, I/H/E, port and polish and the probinator setup for the curved neck. I know that's an unfair test, but the straightneck was over .5 sec slower 0-60, VRIS aside that's alot. I'm sticking with the curved neck for now.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 9:02 am
by Slammed6
A shop tested both Straight neck and Curve neck ZE manifolds on a flow bench. The Curve neck flowed like 10 CFM more than the Straight neck. The Curve neck shows the most power increase over the straight neck through low-mid RPM range.
I had a KL-31 cammed KLZE, with Curve neck manifold, Stock MX-3 air box, Headers, 2.5" Cat-back, and KL-36 ECU. I Dyno'd 180 WHP, which is more than most people dyno with stand alones. I think from all my reading on these forums that is one of the highest, if not the highest, WHP on a factory ECU.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 11:42 am
by wytbishop
So far I'm not totally happy with the performance of my Probinator chipped K801 ECU. I'm not getting great mileage and when the exhaust is done it's likely to get worse. The power seems decent, and I'm sure it will improve noticeably with the exhaust, but I don't think i'll have 180 on the ground.
I think I'm in the market for a KL36 ECU.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 1:08 pm
by colinf004
I have also been doing a lot of reading on these forums in the past few weeks, with the information I have read, I have come up with a solution I would like to have under my hood. 1st off I have 2 KLDE engines and 1 of them is a rebuilt klde engine, kl01 cams, 3deg heads, new exhaust headers, de IM and other small mods..
I am now seeking a curved neck KLZE, take the heads off both ZE and the DE, swap the DE retainers into the ZE, port and do a 3deg on the heads.. for the internals on thats engine.. I am a little fuzy on the kl31, kl01 cams, not sure what I want to do... should I do others internals like, pistons, rods? (might not do a turbo)
once all done sell the remaining DE parts, Need the room.. through in a catback exhaust and poly those engine mounts.
I currently have a kl36 ecu installed
not too sure what a megasquirt does and how it works.. whats up with the extra nipple on the dist. and a coil pack I have seen in pictures. whats that do??
all in all does my ZE requirements make sense?? will I be pushing 200WHP? or close to it?
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 3:13 pm
by marcdh
wytbishop wrote:So far I'm not totally happy with the performance of my Probinator chipped K801 ECU. I'm not getting great mileage and when the exhaust is done it's likely to get worse. The power seems decent, and I'm sure it will improve noticeably with the exhaust, but I don't think i'll have 180 on the ground.
I think I'm in the market for a KL36 ECU.
x2 runs far too rich on WOT. I got megasquirt to try and sort that out, pity it doesn't frickn work.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 4:12 pm
by wytbishop
The theoretical power rating of the ZE engine is 198hp. So it probably puts 160ish to the ground in the majority of cases. The only way to make more power is to increase volumetric efficiency. That means get more air in and out of the engine. Improving the intake and exhaust is the easiest and most common way tot do that, but it will probably only get you 10hp. That being said I'm sure that there are guys out there putting 200 on the ground. These are the guys chasing every little gain. Knife edging the IM, boring the TB, flowing the heads, 3 angle valve grind and on and on.
No combination of heads, cams, valves, etc. will increase your engine's output beyond 170-180hp or so. I would call 180whp the best case scenario without some sort of in depth search for added hp. If you're doing the internals, you coupld bump compression but that would hamper future boosting efforts.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 4:46 pm
by Juans_93_MX3
I got a question for everyone.
I own a straight neck. I am surprised that the curved neck engines make just as much power as a straight neck according to
http://www.geocities.com/viv95pgt/klze.html" onclick="window.open(this.href);return false;
I thought the whole point into getting the straight neck KLZE was because you can swap the manifold and you can already have a set of KL31 CAMs... so whats the point of having KL31 cams if they make just as much power as KL01 CAMs?
How much power are KL31s suppose to make over KL01 CAMs?
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 10:09 pm
by RX8SE3P
Not sure. That site says the curved neck engine can make 200HP. Dunno if it's entirely true, perhaps it has to be a Jap spec curved neck.
I know the curved neck motors in the Eunos 800 here only make 125KW -170HP. They look exactly the same. They use the same cams. I'm not sure how they make 200HP when they seem identical in every way to the 170HP engine?
Mind you, before anyone jumps at this, the Australian spec Eunos 800 does indeed use the same spark plugs as my straight neck ZE. Obviously pistons are the same.
Re: difference in klze curve neck vs. straight neck.
Posted: April 3rd, 2009, 10:32 pm
by Nd4SpdSe
Juans_93_MX3 wrote:I got a question for everyone.
I own a straight neck. I am surprised that the curved neck engines make just as much power as a straight neck according to
http://www.geocities.com/viv95pgt/klze.html" onclick="window.open(this.href);return false;
I thought the whole point into getting the straight neck KLZE was because you can swap the manifold and you can already have a set of KL31 CAMs... so whats the point of having KL31 cams if they make just as much power as KL01 CAMs?
How much power are KL31s suppose to make over KL01 CAMs?
See where the power is made, not the amount of power made
Re: difference in klze curve neck vs. straight neck.
Posted: April 4th, 2009, 10:04 am
by ninjajim4
+1... i've never heard it said that a straight neck make more HP than a curve neck, only shifts the powerband. the only advantage i've ever heard of is that the kl31/36 ECUs are designed for straight necks and so using a curve neck throws off the VRIS points a little.
Re: difference in klze curve neck vs. straight neck.
Posted: April 6th, 2009, 7:39 pm
by Slammed6
Juans_93_MX3 wrote:I got a question for everyone.
I own a straight neck. I am surprised that the curved neck engines make just as much power as a straight neck according to
http://www.geocities.com/viv95pgt/klze.html" onclick="window.open(this.href);return false;
I thought the whole point into getting the straight neck KLZE was because you can swap the manifold and you can already have a set of KL31 CAMs... so whats the point of having KL31 cams if they make just as much power as KL01 CAMs?
How much power are KL31s suppose to make over KL01 CAMs?
The power increase is made through the intake manifold, from what i remember reading. So that is why putting a curve neck manifold on a KLZE with KL-31 cams is suppose to make more power.
I said in another post the Curve neck manifold out flows the straight neck by a long shot through mid RPMs, and in upper RPMs it was shown to flow slightly better.
I also remember there was a big bebate on KL-01 stamped KLZE cams being the same SPEC as the KL-31 stamped KLZE cams...but i never really believed that.
Re: difference in klze curve neck vs. straight neck.
Posted: April 7th, 2009, 3:35 am
by Tommy
RX8SE3P wrote:I had a big arguement with custommx3 about this one, my opinion is that while the curved neck is closer to a ZE than it is to a DE, it's still not as powerful.
The curved neck engine is out of millenias, I think. I know they come out of Eunos 800s here, is that the same car as a millenia? Australia uses weird names, our MX3 is called a 30x.... I've seen engine bays of 2.5L Eunos 800s and they are the curved neck engine. They are rated for 170HP, 125KW. I've read this from my insurance car guides site. It's also widely posted in other places that the curved neck engine has 170HP.
They use the same spark plugs as a ZE. This to me means they might have the same pistons too. I've noted that DE spark plugs are much longer than ZE ones. The Eunos 800 definitely uses ZE spark plugs. However it is tuned for regular octane petrol. The curved neck engine uses KL01 cams. Same from the DE. These keep torque in the lower revs a little better but it doesn't peak with power like the straight neck.
IMO the TRUE ZE is the straight neck engine. I like to call it the KL31 engine. The KL31 has KL31 cams, KL31 heads, KL31 ECU, KL31 throttle body, KL31 pretty much everything! It's tuned for higher octane petrol. It makes 200HP, 149KW.
Now I know that you can use either intake manifold and it won't affect you but I am pretty sure the curved neck engine in general is not as fast as the KL31 straight neck.
Your referring to the KLG4 with the curved neck in the millenias and i also think there weak but it also was a ATX o well
Re: difference in klze curve neck vs. straight neck.
Posted: April 7th, 2009, 3:40 am
by Tommy
wytbishop wrote:The theoretical power rating of the ZE engine is 198hp. So it probably puts 160ish to the ground in the majority of cases. The only way to make more power is to increase volumetric efficiency. That means get more air in and out of the engine. Improving the intake and exhaust is the easiest and most common way tot do that, but it will probably only get you 10hp. That being said I'm sure that there are guys out there putting 200 on the ground. These are the guys chasing every little gain. Knife edging the IM, boring the TB, flowing the heads, 3 angle valve grind and on and on.
No combination of heads, cams, valves, etc. will increase your engine's output beyond 170-180hp or so. I would call 180whp the best case scenario without some sort of in depth search for added hp. If you're doing the internals, you coupld bump compression but that would hamper future boosting efforts.
160ish ZE????? damn you might as well stick with a DE rated @ 164-170
Re: difference in klze curve neck vs. straight neck.
Posted: April 7th, 2009, 3:48 am
by RX8SE3P
Tommy wrote:Your referring to the KLG4 with the curved neck in the millenias and i also think there weak but it also was a ATX o well
Is it a KLG4?? I've never heard of that. They are meant to have 125KW, more power than a DE - 121KW.
Here's an engine bay pic. They look just like "curved neck ZE". How would you tell this apart from a 200HP curved neck? They look identical. Head codes are probably the same too. Would the cams be KL31? I guess if it was a ZE version it would have a 7 nipple disty and no EGR etc.
Here's a pics, they are found in Eunos 800
Re: difference in klze curve neck vs. straight neck.
Posted: April 7th, 2009, 8:38 pm
by Mooneggs
Tommy wrote:160ish ZE????? damn you might as well stick with a DE rated @ 164-170
we're talking power at the wheels not the crank... 200hp ZE puts out about 160-165 at the wheel normally