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The opinion carried in the forum is that installing a DOHC engine cannot be done, because the heads/timing gear foul the chassis rails. At least, this is how I understand it. This requires the chassis rails to be "chamferred" at the front, to clear the timing gear.

Has anyone verified what actually fouls? Is it the timing gear, or is it the timing gear cover? It "appears" to the naked eye, that it is just the cover, which, could either be modified, replaced with a custom jobby, or removed to allow the engine to just bolt in. FOr a car with no serious off orad aspirations, this should be fine.

ANy of the "converters" wish to comment?

It's the plastic timing covers. But I believe the actual cam sprockets themselves will still foul or at least come dangerously close to the chassis rails if the plastic covers weren't there.
Modifying the chassis rails is a MINOR modification (not even structural) to a car that is most likely worth less than the engine you are putting into it. It's the best solution to this problem. You only have to do it once, just do it and it's done

AndrewT wrote:...chassis rails...(not even structural).

?

Daza.

yeah, I have the same question as Daza ... the chassis rails would HAVE to be a structural mod? Unless you fill the holes it'd have to weaken things especially in case of a head on smash...

The mods are only required on the sections of the chassis rails which are in front of the strut towers. Their only real job is to hold the headlights, front bumper and radiator in place - no relation to crossmember mounts, strut mounts, any other important mounts like radius rods etc.
Naturally when you slice the very small section out which is required for clearance, you shut it again with a replacement piece of metal just to be sure.
There are a few very detailed write-ups on this board with photos and a few different methods.

This has been covered a fair bit before. The mod that was posted here previously entailed cutting slots into the chassis rail top and underneath and then "massaging" the engine side of the chassis rail back in to fill up the slot. The repair is then welded and finished. A good job with a good finish would look ok not attract too much attention by prying eyes.

The ea82 in my brumby which has the sohc has just had a slot cut into the rail for the timing cover. (Photos here somewhere) The tappet covers just miss the chassis rail further back.

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This would be the third or fourth time I have seen the "chassis rail mods are covered elsewhere in the forum" comment....call me stupid, but I can find no detailed thread showing options, methods, measurements with pictures. Feel free to prove me worng and post the link here >

Here's the thread where you were told last time;
showthread.php?t=9852&highlight=rail

Here's that thread u were told about then;
showthread.php?t=8294

Here's one more resulting from a quick search;
showthread.php?t=6799&highlight=rail

Check em out - some excellent pics and information. Some more extreme than others.

Yes, you are proving my point precisely...that makes it three times that someone said its all be done, and provide a link to something which isnt what I am after.....

AndrewT wrote:Here's the thread where you were told last time;
showthread.php?t=9852&highlight=rail

I presume you mean this "photo": attachment.php?attachmentid=776&d=1205053949
in which case, this is a "photo, not a detailed siscussion of options etc. I did look at this at the time.


Here's that thread u were told about then;
showthread.php?t=8294

as per above, links thru to same thread.

Here's one more resulting from a quick search;
showthread.php?t=6799&highlight=rail

but this one, is exactly what I was asking for...thanks Andrew.

Check em out - some excellent pics and information. Some more extreme than others.

Those links have heaps of info, photos and everything. I think you are making too much of a big deal out of the mod in question. If your modifying your car you have to have at least some ability to think for yourself and improvise. Nobody else needs info that detailed.
Just test fit the motor. In about 3 seconds flat you will see what clearance it requires.
Cut a bit of metal out, weld another bit in to patch it, and your done.

AndrewT wrote: Just test fit the motor. In about 3 seconds flat you will see what clearance it requires.
Cut a bit of metal out, weld another bit in to patch it, and your done.

+1
If your not satisfied with the responses and information supplied simply try it yourself.
Then you can post up a tech and tell us all what we do/don’t already know.

Hey guys, read my response...one of the threads was exactly what i asked for, and I said "thankyou".

In Victoria, it is substantially more difficult to get cars passed after modifications than elsewhere...I was just asking for options. I dont have an engine to test fit, because Im not buying an engine until i know what modifications have to be done on the chassis, so I can get a VASS engineer to give me the nod that he will approve it. Now that I have the photo from the third thread provided, I can show an engineer, and if he gives me the nod, i can go DOHC.

Sorry mate didn't notice your thankyou as it was included in amongst a "quote" of my own text.
Good luck with the engineering, hopefully you get the nod, I don't expect it will be much of a problem.

Gosh, I gotta get me some photos of an EA82T in a Brumby I have seen with no rail mods and it is standard height and it clears everything. The photo above now makes me question my visual inspection of witnessed install....

Hamish,

When you find the VASS engineer that passes your intended mod, could you please forward their number onto me? I got a few mods that i would like engineered so the car is legit, you know how the cops are around here...

Cheers

Bennie

If the DOHC engine was mounted without spacing it down an inch would you still need to mod the chassis rails? what about the gearbox does the inch spacing help it fit aswell?
Surely we could find another way to get the bonnet clearance, low profile intake manifold or modified bonnet.

Prunes wrote:Surely we could find another way to get the bonnet clearance, low profile intake manifold or modified bonnet.

Or a lift kit If your car is a black top based car you would be better off spacing the engine crossmember down - it improves the CV joint angles and would, in my mind, give you better camber (if i'm talking about the correct angle of the wheel -> going from this: \ - / to this: /-\)

Cheers

Bennie

El_Freddo wrote:Or a lift kit If your car is a black top based car you would be better off spacing the engine crossmember down - it improves the CV joint angles and would, in my mind, give you better camber (if i'm talking about the correct angle of the wheel -> going from this: \ - / to this: /-\)

Cheers

Bennie

+1

I just love the way you have described the camber lol
But have lowered a few cars, Some way too low byt in some cases this mod was needed.