Block difference
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turbotruck
- Posts: 62
- Joined: Tue Mar 09, 2004 1:24 pm
Block difference
Is there a difference between a 90 ka24e block out of a 240 and one in a 97 in a hardbody.. I need to build a shortblock and just want to make sure if i do i can slap it in NO problem!
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deviousKA
- Posts: 1355
- Joined: Tue Aug 12, 2003 5:04 pm
- Car: 90 240sx NA /72 Datsun 510 NA /86 corolla GTS NA
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Yes there are a few major differences. The biggest problem is that the 240 block uses a different offset flywheel (and a different starter motor to match). Now, you can use this setup in a truck, but you will have to modify the starter motor (on a truck, the starter bolts go through the starter and thread into the transmission, on a 240, its the opposite, they go in from the back and thread into the starter). So all you would have to do is drill out the tapped threads in the 240 starter, and hope you have the right length bolts to go to the truck transmission. Truck starter cannot be used with 240 block. The different offset flywheel should work ok in the truck, you have to keep the 240 flywheel with the 240 block. The 240 flywheel is a tad smaller mating diameter than the truck (225mm vs 240mm) so you would have to use the smaller 240 clutch which should work ok in a 2wd, but i wouldnt do it in a 4x4 hardbody.
Ok that takes care of the flywheel situation, other differences between the blocks include a full main cap girdle vs. seperate main caps of the truck (for the crankshaft). This poses a oil pan clearance problem, if you doing it on a 2wd hardbody it should work ok, but i know for sure that a 4x4 hardbody pan does not work with 240 block, without modification. Another thing to add, im not sure about this, but i have heard that the motor mount location on the blocks could be different? not entirely sure.
The timing cover/chain and setup, cylinder head (aside from cam) are all the same between the two. Oh and forgot to add, the truck rods/pistons use a press fit 21mm piston pin, vs. full floating 21mm of the 240. These parts are somewhat compatable (truck pistons wont work with 240 rods, 240 pistons wont work with truck rods, 240 piston/rod will work in truck block, truck piston/rod will work in 240 block).
Ok thats about all that is majorly different. The truck head/block is cast in mexico vs. 240 head/block cast in japan. The truck block is actually marginally better than the 240 block from a performance standpoint (because of the thicker cylinder walls and seperate main caps). Heads are really no different except for the mexico truck heads casting doesnt "look" as nice.
Search for a thread by McAdam, he swapped a 240 sohc engine into a 4x4 hardbody.
Oh btw. I almost forgot. Because you have a 97 hardbody, it uses the "large port" ka24e head. Im not sure if the intake/exhaust manifolds will work with an older ka24e small port (which is better performer than the large port i hear). If this becomes a problem you will need to either use your truck head, or swap to a pre-95 truck manifolds, or just swap the 240 intake manifold system on for some more power.
I would say this answers your question thoroughly, good luck!
Edit: I got bored and searched for you because i am search masta! Heres that post.
http://www.nissaninfiniticlub....35881
Ok that takes care of the flywheel situation, other differences between the blocks include a full main cap girdle vs. seperate main caps of the truck (for the crankshaft). This poses a oil pan clearance problem, if you doing it on a 2wd hardbody it should work ok, but i know for sure that a 4x4 hardbody pan does not work with 240 block, without modification. Another thing to add, im not sure about this, but i have heard that the motor mount location on the blocks could be different? not entirely sure.
The timing cover/chain and setup, cylinder head (aside from cam) are all the same between the two. Oh and forgot to add, the truck rods/pistons use a press fit 21mm piston pin, vs. full floating 21mm of the 240. These parts are somewhat compatable (truck pistons wont work with 240 rods, 240 pistons wont work with truck rods, 240 piston/rod will work in truck block, truck piston/rod will work in 240 block).
Ok thats about all that is majorly different. The truck head/block is cast in mexico vs. 240 head/block cast in japan. The truck block is actually marginally better than the 240 block from a performance standpoint (because of the thicker cylinder walls and seperate main caps). Heads are really no different except for the mexico truck heads casting doesnt "look" as nice.
Search for a thread by McAdam, he swapped a 240 sohc engine into a 4x4 hardbody.
Oh btw. I almost forgot. Because you have a 97 hardbody, it uses the "large port" ka24e head. Im not sure if the intake/exhaust manifolds will work with an older ka24e small port (which is better performer than the large port i hear). If this becomes a problem you will need to either use your truck head, or swap to a pre-95 truck manifolds, or just swap the 240 intake manifold system on for some more power.
I would say this answers your question thoroughly, good luck!
Edit: I got bored and searched for you because i am search masta! Heres that post.
http://www.nissaninfiniticlub....35881
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deviousKA
- Posts: 1355
- Joined: Tue Aug 12, 2003 5:04 pm
- Car: 90 240sx NA /72 Datsun 510 NA /86 corolla GTS NA
- Contact:
I havent had any of the big port heads off of vehicles to see the actual differences. I have heard from various people and other sources that the ports are larger, but from what they have gathered for some reason the earlier heads have better flow. I assume nissan redesigned the port in other ways besides making it larger, most likely to gain some added torque (they have implemented designs like this before in their heads, reversion bulges? for lack of a better term). Toyota has also done this in their later truck engine versions, starting in ~1986.
This is why the nissan nap-z heads are unpopular (nothing to do with 8 spark plugs although this is an emissions thing), The port designs were changed to gain torque features. The first nap-z head is actually a decent flowing one, the z20, after that top end performance was sacrificed due to the nap-z being used solely in the trucks.
this is all assumption but im sure the change in ka24e goes along with this idea. The later ka24e truck engines also used different distributors and side feed type injectors. Throttle body system stayed basically the same even over into the ka24de truck versions.
Another possibility is that the head intake ports are larger to allow room for the different type injectors. Sort of like the way the port is designed in ka24de.
This is why the nissan nap-z heads are unpopular (nothing to do with 8 spark plugs although this is an emissions thing), The port designs were changed to gain torque features. The first nap-z head is actually a decent flowing one, the z20, after that top end performance was sacrificed due to the nap-z being used solely in the trucks.
this is all assumption but im sure the change in ka24e goes along with this idea. The later ka24e truck engines also used different distributors and side feed type injectors. Throttle body system stayed basically the same even over into the ka24de truck versions.
Another possibility is that the head intake ports are larger to allow room for the different type injectors. Sort of like the way the port is designed in ka24de.