Also, take into consideration the space requirements. i have a little room left with the SOHC 24v. the DOHC heads are taller and wider than the SOHC heads. so in the application of a duster, you MAY not have enough room. the Timing belt is also a different length, and im not sure where the 3/S tensioner is or whatnot. Might want to take a look at the headgaskets as well to see if the coolant/oil passageways match up. i know the 12v and 24v heads are damn near identical but who knows. another good point brought up is that the DOHC heads do not dave a distributor, they ran a DIS system. so a standalone like MS with the ford EDIS system would probably be needed to make the DOHC heads work on the 12v block.
IMO the 24v SOHC heads are no slouch, granted ou dont have the adjustability of the DOHC, but they are still a good option considering. coupled with the low compression of the 12v pistons (8.8:1 compared with the 9:1 or 10:1 for the 24v SOHC donor motors) makes a prime boost candidate. some ring regapping and minor work would make a fine boosted motor. but thats just my $.02
Dyne proof? I know I am still looking for somebody with a stock 3L to put it on the dyne. Nobody has been willing to step up to the plate.
Also, as you examine Brent's "proof", remember that there are many factors that go into acceleration. Hp is just one of them. Weight and gearing are two more...
Last I checked 3.50 gears are the longest stock gears, and I was running taller tires then anyone here (~25.5), and I weigh my car..................
Please dont call bullshit on me like that.
Also, take into consideration the space requirements. i have a little room left with the SOHC 24v. the DOHC heads are taller and wider than the SOHC heads. so in the application of a duster, you MAY not have enough room. the Timing belt is also a different length, and im not sure where the 3/S tensioner is or whatnot. Might want to take a look at the headgaskets as well to see if the coolant/oil passageways match up. i know the 12v and 24v heads are damn near identical but who knows. another good point brought up is that the DOHC heads do not dave a distributor, they ran a DIS system. so a standalone like MS with the ford EDIS system would probably be needed to make the DOHC heads work on the 12v block.
IMO the 24v SOHC heads are no slouch, granted ou dont have the adjustability of the DOHC, but they are still a good option considering. coupled with the low compression of the 12v pistons (8.8:1 compared with the 9:1 or 10:1 for the 24v SOHC donor motors) makes a prime boost candidate. some ring regapping and minor work would make a fine boosted motor. but thats just my $.02
I know at least 1 dohc motor has decided to run a solid timing belt tensioner.....so you could probably fab up a timing belt tensioner that would be "good enough" to hold the dohc timing belt. the stock timing belt tensioner for the dohc is not solid but I cant remember how it works.....whether its hydraulic or sprung.
Last I checked 3.50 gears are the longest stock gears, and I was running taller tires then anyone here (~25.5), and I weigh my car.................. Please dont call bullshit on me like that.
My van runs 225 60 15 Dunlop A2 which according to tirerack.com are 25.5" Daytonastein runs 225 60 15 Kuhmo's. Tirerack does not currently list the height, but I am pretty sure they are taller than the Dunlops (they fit tighter in the wheel well than the Dunlops did.)
My van can walk away from Mike's Eclipse... The Eclipse dyned with more hp, but my van is still quicker... Even with the greater frontal area of the van.
Proof? Also, you are going to have to be more specific. Which SOHC engine are you talking about? 12 or 24 valve?
ED the Dohc engine is flat out overrated by about 15hp or more at the crank.
you dont have a 165FWHP car that is rated at 220crank hp. 25% drivetrain losses through a FWD manual trans? I think not.
By that math the 140hp sohc 12v should dyno 105whp stock.
From what I have seen the "205crankhp" eclipse makes the same REAL hp as the "220crankhp" dohc motor. That makes me laugh.
but even the sohc 24v probably is a bit to generous on its crank HP rating. 19%+ drivetrain loss is not realistic
One wrench to throw in the deal is that I believe SAE rules for brakehp ratings changed. Manufacturers used to be able to engine dyno with zero accesories and stuff like that......that automatically inflates those older numbers.
Also remember that chrysler had a 4 cylinder turbo engine to compete with that was already rated 150hp (maybe it actually made more or less then that) but regardless there is no way they would rate the turbo motor lower then the n/a v6.
Just remember that the turbo motors only made 142hp or so until the v6 came out then all of a sudden they made 150hp while the v6 made 140hp......then all of a sudden when the turbo motors are gone, they barely increase compression and HP is now rated at 150hp even with "new" SAE HP rating rules in 2000 or so. Not proof of anything but just a plausible alternative to believing manufacturers who have been getting sued the last few years about lieing on their HP numbers.
+1 on the overrated hp numbers. the 24v is "rated" at 205/205, real world numbers with a 5sp are at most around 185hp. autos were in the low 170s. the n/a DOHCs were weaker, possibly due to the lesser torque curve.
Interesting Conspiracy theory. However the change from gross to net hp that you mentioned happened in 71/72... Then the next change to the hp testing rules was in 2005, long after the 12v was out of production...
To the best of my knowledge there was no significant change in the SAE rules in 2000.
Turbos and supers make an engine very easy to increase hp... Generally manufactures limit hp so that the transmission can reliably survive through the warrenty period... As transmissions are modified to handle more hp, boost is turned up or comes on earlier.
I can't see a manufacture getting sued for underrating a 141hp engine. Maybe for underrating a 400hp engine.
Quote:
Originally Posted by Ondonti
One wrench to throw in the deal is that I believe SAE rules for brakehp ratings changed. Manufacturers used to be able to engine dyno with zero accesories and stuff like that......that automatically inflates those older numbers.
Also remember that chrysler had a 4 cylinder turbo engine to compete with that was already rated 150hp (maybe it actually made more or less then that) but regardless there is no way they would rate the turbo motor lower then the n/a v6.
Just remember that the turbo motors only made 142hp or so until the v6 came out then all of a sudden they made 150hp while the v6 made 140hp......then all of a sudden when the turbo motors are gone, they barely increase compression and HP is now rated at 150hp even with "new" SAE HP rating rules in 2000 or so. Not proof of anything but just a plausible alternative to believing manufacturers who have been getting sued the last few years about lieing on their HP numbers.
Interesting Conspiracy theory. However the change from gross to net hp that you mentioned happened in 71/72... Then the next change to the hp testing rules was in 2005, long after the 12v was out of production...
To the best of my knowledge there was no significant change in the SAE rules in 2000.
Turbos and supers make an engine very easy to increase hp... Generally manufactures limit hp so that the transmission can reliably survive through the warrenty period... As transmissions are modified to handle more hp, boost is turned up or comes on earlier.
I can't see a manufacture getting sued for underrating a 141hp engine. Maybe for underrating a 400hp engine.
had no idea about when they actually changed that HP rule.
The fact is that the motors are overrated, the proof is all over every dyno sheet ive ever seen and every complaint Ive seen from actual owners.
Investigate the Rx-8........people were trying to sue but mazda gave them the "right" to trade back in their car for a full refund to avoid that false advertising.
not sure what your tranny blah blah has to do with overrating engines.
As far as underrating, exact HP numbers you see on the sticker are more calulated by bean counters. Psychologically those things make a huge difference in how customers buy a new car. add 5 hp to 1 car, take 5 from another, and all of a sudden you justify the upgrade for a few thousand dollars. This is especially true when you are selling to people who dont know anything about cars, or realise that HP doesnt mean everything (which is almost everyone)
had no idea about when they actually changed that HP rule.
The fact is that the motors are overrated, the proof is all over every dyno sheet ive ever seen and ever complaint Ive seen from actual owners.
Is the 12V over or underrated? Depending on how you read several of the statements in this thread, you could be saying both... I have been talking about the 12v being "underrated"...
Quote:
Investigate the Rx-8........people were trying to sue but mazda gave them the "right" to trade back in their car for a full refund to avoid that false advertising.
Since when is the Rx-8 a 141hp minivan????
Quote:
not sure what your tranny blah blah has to do with overrating engines.
You mentioned the 2.2/2.5 turbo engine "magically" changing it's hp... There are very reasonable explainations that are not consipiratorial...
Is the 12V over or underrated? Depending on how you read several of the statements in this thread, you could be saying both... I have been talking about the 12v being "underrated"...
Would you like me to quote about 20 different times I have said "dohc" motor in various threads?
Do i really need to go and post dyno sheets again?
Do I need to post 3000gt threads that are called "dohc na overrated"????
Quote:
Originally Posted by c2xejk
Since when is the Rx-8 a 141hp minivan????
Did I ever say it was? Do I even own a minivan? Please explain the logic that states that HP numbers are somehow more or less defensible because you are talking about a sporty car?
Quote:
Originally Posted by c2xejk
You mentioned the 2.2/2.5 turbo engine "magically" changing it's hp... There are very reasonable explainations that are not consipiratorial...
There were changes to the motors but I would say the 142 and the 150 are not actual exact numbers, but arbitrary ways of showing "improvement". The difference might be correct but that doesnt mean the actual number is.
Do you think adding .45 compression adds 10hp to a 140hp car BTW????Maybe 2hp. increased timing etc on the ODBII isnt going to get you there either because james Dempsey already showed that there isnt much to gain with timing advance. He only found 5hp..........and that was on a modified engine. Doubtful the odbII 3.0 computers even contribute to more hp.
The 224hp dohc 2.2 chrysler will dyno 35-45whp more then a 220hp mitsu dohc v6 when both are stock........Here you have chrysler underating a motor. It doesnt even make sense in this case.........If they were rating HP like mitsu does for its 24v motors then the 2.2 dohc chrysler would be rated as making 275hp.
One of these days you guys will start understanding that manufacturer hp numbers are rarely an accurate representation of actual power production and that there are other variables that come into play when it comes to the sticker on your new car.
Magazine benchracing is lame enough........Window sticker benchracing has got to be one of the lamest practices ever.
TurboDodge.com 
Even with the greater frontal area of the van.
