Smurf accord

Ok hope y'all can help. I have a 94 accord ex and I found a guy that has a 98 sh h22 motor and tranny. I was wondering if it worth the time of doing bc I have read the block are different and what not. And will the tranny work even without that atts unit?

Sir S-Spec

The motor will run without the ATTS working. A lot of SH owners have disconnected theirs because of trouble codes.

I wouldn't go for an SH motor because the differences between the base and SH setup make it difficult to find parts. A header for example is not interchangeable between the two, so if you want something that is for a base, it won't fit unless the company makes an SH version. That is the biggest gripe that SH owners have.

Smurf accord

Alright so let's say I was to do it and I can get the motor and tranny for 400 but the motor needs rebuilt... still say not worth it? And what the guy I would be buying this from said if u don't hook up that atts unit its just locked all the time is that true or no?

Sir S-Spec

How much is the rebuild? Are you doing it yourself? Chances are the purchase of this engine/transmission + the (proper) rebuild are going to be more than what a running condition base motor and transmission will cost you. I've seen JDM H22's for $1000-$1500, direct swap.

You can drive with the ATTS unit installed but not functioning, lots of SH owners do it. All it will be is dead weight. I know an H22 will fit in an 94 Accord, but another thing to consider is, will an H22 with an ATTS transmission fit? The ATTS unit is large enough to necessitate SH-specific parts on a lude, so if you are determined to go for this engine, make sure it will fit with everyhting that is in your bay.

Sir S-Spec

How much is the rebuild? Are you doing it yourself? Chances are the purchase of this engine/transmission + the (proper) rebuild are going to be more than what a running condition base motor and transmission will cost you. I've seen JDM H22's for $1000-$1500, direct swap.

You can drive with the ATTS unit installed but not functioning, lots of SH owners do it. All it will be is dead weight. I know an H22 will fit in an 94 Accord, but another thing to consider is, will an H22 with an ATTS transmission fit? The ATTS unit is large enough to necessitate SH-specific parts on a lude, so if you are determined to go for this engine, make sure it will fit with everyhting that is in your bay.

holmesnmanny

The Base and SH use the same exact exhaust manifold. Blockwise, they're essentially the same for all intended purposes. Perhaps they use a different exhaust system downstream of the manifold, but even so, that's completely irrelevant. Just take your tranny and mate it with that block and you're good to go. You simply can't use the SH tranny that's all.

MAD_MIKE

ATTS unit is in place of the intermediate shaft on MT cars. SH blocks are slightly different as the ATTS unit takes up the space where the oil filter is normally. This required relocation of the oil filter closer to the timing cover, and the bolt bosses for the ATTS are in a different location than where the intermediate shafts bolt bosses are located.
ATTS can be disconnected and the default should be that the ATTS just acts as an intermediate shaft. But this is still a rather large unit and will be dead weight on the car, and possibly be an interference issue when installed into an older Accord. ATTS also has its own pump which needs to be hooked up to keep the ATTS lubricated, otherwise it may seize up.

IMO if your current Accord has an MT or plan on changing to an MT later and not implementing the ATTS, skip on this block/trans combination as it is unique to the ATTS/SH Preludes.

holmesnmanny

Just to be sure, he should be able to use his Accord tranny with that block with no issues, right Mike?

If not, I will stand corrected.

MAD_MIKE

From the one block I saw the bellhousing appears to be the same pattern. And AFAIK the 'SH' 'ATTS' transmission is not outwardly different from any other F/H MT trans, same basic case/structure/mount points. It just has this big ole honking unit bolted to the back of the block to the left of the diff housing.


The big PITA with the SH block is where the intermediate shaft on a typical MT F/H series bolts, there are no bolt bosses to accommodate it. There are two bolt bosses further to the front of the engine(and two towards the rear/bellhousing), or left when sitting in the car, but they are not aligned or designed to be used with the standard('Base') intermediate shaft.

I have seen a few people use a steel plate to bolt to the block then bolt a standard MT intermediate shaft to this plate, however no one has ever stated if this keeps the intermediate shaft inline with the differential. My guess is this pushes the shaft rearwards, putting a bending load on the shaft and probably not doing the side differential bearings any favor either. One could probably use an AT one piece axle to avoid the bending loads but then there would be the unbalanced torque steer from the longer axle.

IMO if someone wants/needs to use the SH block they should have a plate made with an offest recess in it to allow the standard 'base' MT intermediate shaft to lay in the correct plane and not allow misalignment. IIRC the four bolt bosses on the SH block for the ATTS unit are closer to the front and rear of the block, which would allow enough clearance to allow for an adapter plate, with the correct recess, to sit. But I doubt anyone would bother make such a thing for such a low production sub model conversion.

EDIT: One other thing of note, due to the oil filter being moved closer to the front of the engine, there was some hose changes as well, and I *think* the waterpump to thermostat housing water pipe was also different to clear the ATTS unit. All in all there are several differences with the SH block that IMO does not make it a worth while swap into a non SH/ATTS car unless the engine is being given away. Plenty of standard H22/H23s still out there.

MAD_MIKE

Just did a quick gargoyle search and stumbled on this...
http://www.preludeonline.com/f89/atts-removal-147883/

Standard H block


SH ATTS H block


According to BoosterSH
So if the ATTS tranny is not even reusable, more reason to avoid the SH/ATTS drivetrain.

holmesnmanny

http://www.preludeonline.com/f60/base-vs-sh-229597/

I'm gonna stand corrected from a tranny bolt up standpoint.

It would definitely be best not to get the SH block as you will need to fabricate to make it work. It's not possible but will take some work.

Smurf accord

Alright thanks for all of that it really helps now I do know what to look for and everything

The only reason I was even looking into all this was bc my tranny the differential actually blew apart and there's a huge hole in the back of my tranny so I'm trying to find a tranny but that's about damn near impossible...

What could have caused that tranny to do that? Any ideas?

holmesnmanny

The bearing could have gotten so bad that it seized up and destroyed the tranny, similar to when you spin a bearing in the motor and throw a rod.