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Old 07-13-2001, 09:30 PM   #1
Root Moose
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Default How to identify Phase I or Phase II block?

I have a late 98 2.5RS. I understand that some of these cars may have come with the slightly stronger phase II block but had DOHC heads.

How do I identify which block I have?

T!
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Old 07-13-2001, 10:42 PM   #2
cakagan
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Here's the thread from awhile ago...
Attn: All '98 2.5RS Owners - Survey

You'll probably find a picture of it at Cobb Tuning's site.

-Chris
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Old 07-13-2001, 11:37 PM   #3
Root Moose
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Cool Other source for picture?

I read the thread you supplied (thanks, btw).

The image that Trey had originally posted is a dead link now. But...looking at these two images:

Phase I Block Ridges

Phase II Block Ridges

It looks like my DOHC has a Phase II Block.

Woohoo!



[Edited the links to point at the images sitting on my site so Cobb Tuning doesn't get hit for extra bandwidth charges because of this post - the images above originated from Cobb Tuning]

Last edited by Root Moose; 07-13-2001 at 11:49 PM.
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Old 07-14-2001, 11:01 AM   #4
cakagan
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Default Nice...

Root-

Thanks for posting those pics, now I see what Cobb was talking about. I used to have the Phase I engine, but due to oil consumption probs, they tore it open and saw that cyllinder walls on 1-3 were badly scored. So now I'm breaking in a new Phase 1.5 motor! Gotta love extended warranties...

-K
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Old 07-17-2001, 02:22 PM   #5
ColinL
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Unfortunately Trey later posted that he's seen blocks that don't conform to his "rule" although most are correct.

If it's 8bolt it should be phase II by all rights...
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Old 07-17-2001, 03:07 PM   #6
Root Moose
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Default Good!

Good to hear - I had been reading about 4 bolt vs 8 bolt and was wondering if there was a correlation.

Does the number of bolts mean the bellhousing is different or is it the entire transmission that is different?
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Old 07-17-2001, 03:13 PM   #7
ColinL
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The bellhousing and tranny are the same shape, it's just that the four bolt models have pegs instead of 4 extra bolts.

I think if you were to use one of the latest trannies with 11 bolts you'd have to make minor modifications, but the bellhousing and tranny are still in the same shape.

If I had a bolt count mismatch between tranny and bellhousing, I'd modify whichever part had fewer to get the higher fastener count. Less tranny flex...
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Old 07-17-2001, 03:33 PM   #8
Root Moose
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Default Tranny Flex

I've heard rumours that a combination of tranny flex and small gear size is what makes these trannies fail in high power applications. I have seen the same thing with Suzuki Samurai drivetrains in off-road conditions.

Replicating the bell housing in steel might help a little bit - but probably not cure the problem. Do you know how many bolts between the tranny and the bellhousing?

This not having a shop manual becasue they are ridiculously priced really sucks! I'd gladly pay ~$150 for the manuals on fiche or ROM...
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