'85 Replacement Engine
Thread Starter
Instructor
Joined: Nov 2004
Posts: 195
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From: San Bernardino & Orange County CA
Need Recommendaion on '85 Replacement Engine
Looking for options to replace the engine in my '85. New crate engines preferred. Stock and moderate step up engine under consideration. This is my daily driver and I'm dead in the water. Thanks.
Last edited by willi.anton; Feb 8, 2006 at 11:14 AM.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 195
Likes: 0
From: San Bernardino & Orange County CA
I'm dying to rebuild mine, but don't have the facilities to do so. I'm working with a Vette only mechanic who is recommending a crate engine. I think he likes the faster fix and warranty. I spoke to Jaspers today and they priced out a stock remanufactured long block. Good suggestion. It sounds like GM new is not available.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 195
Likes: 0
From: San Bernardino & Orange County CA
Every mechanic and GM Parts itself says that the zz4 and other "crate engines" are pre-emmission certified only. In Calif this is too risky for a daily driver. Darn shame because these motors sure sound sweet.
In the new news category - My Vette mechanic tells me he replaces the L98 engine with a "GM Target Engine" which is a L48 long block. All systems including the TPI from the old engine bolt direct to the new block. Why I asked is this solution not more widely reported. It's not a mystery he states, the L98 is essentially a L48 with the TPI. The new engine setup performs identical to the old engine.
Why the "target engine" isn't sold as a "crate engine" I don't know. Must be some meaning to the word crate I don't get. The Target Engine is about $ 1200. Sounds good to me. Original number engine doesn't seem to be of concern as the '85 may never be a classic, although it's my classic.
In the new news category - My Vette mechanic tells me he replaces the L98 engine with a "GM Target Engine" which is a L48 long block. All systems including the TPI from the old engine bolt direct to the new block. Why I asked is this solution not more widely reported. It's not a mystery he states, the L98 is essentially a L48 with the TPI. The new engine setup performs identical to the old engine.
Why the "target engine" isn't sold as a "crate engine" I don't know. Must be some meaning to the word crate I don't get. The Target Engine is about $ 1200. Sounds good to me. Original number engine doesn't seem to be of concern as the '85 may never be a classic, although it's my classic.
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Joined: Feb 2004
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Originally Posted by willi.anton
Every mechanic and GM Parts itself says that the zz4 and other "crate engines" are pre-emmission certified only. In Calif this is too risky for a daily driver. Darn shame because these motors sure sound sweet.
In the new news category - My Vette mechanic tells me he replaces the L98 engine with a "GM Target Engine" which is a L48 long block. All systems including the TPI from the old engine bolt direct to the new block. Why I asked is this solution not more widely reported. It's not a mystery he states, the L98 is essentially a L48 with the TPI. The new engine setup performs identical to the old engine.
Why the "target engine" isn't sold as a "crate engine" I don't know. Must be some meaning to the word crate I don't get. The Target Engine is about $ 1200. Sounds good to me. Original number engine doesn't seem to be of concern as the '85 may never be a classic, although it's my classic.
In the new news category - My Vette mechanic tells me he replaces the L98 engine with a "GM Target Engine" which is a L48 long block. All systems including the TPI from the old engine bolt direct to the new block. Why I asked is this solution not more widely reported. It's not a mystery he states, the L98 is essentially a L48 with the TPI. The new engine setup performs identical to the old engine.
Why the "target engine" isn't sold as a "crate engine" I don't know. Must be some meaning to the word crate I don't get. The Target Engine is about $ 1200. Sounds good to me. Original number engine doesn't seem to be of concern as the '85 may never be a classic, although it's my classic.
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Burning Brakes
Joined: Nov 2003
Posts: 914
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From: Redding Ca
Every mechanic and GM Parts itself says that the zz4 and other "crate engines" are pre-emmission certified only. In Calif this is too risky for a daily driver. Darn shame because these motors sure sound sweet.
About 5-years ago I talked with GM reps at an NHRA nat'l event at Sears Point, Ca and asked directly whether the ZZ4 would pass the Cal tailpipe test. The first (younger) guy would not commit, but an older rep there overheard my question and the answer I got and stepped in. He said the ZZ4 will pass the Ca emissions tailpipe test
but had no EO#.
The ZZ4 is essentially an L98 engine with a little bigger cam and slightly higher compression. There should be no problem with smog.
The ZZ4 does have aluminum heads and I believe the pre '87 L98's have cast iron. It would take a savvy smog tester to pick up on that since GM aluminum has been around now for nearly 20-years. This last year I asked a local smog station guy about what they look for during smogging. He said, speaking, for himself, as long as the visible parts say "GM" there is nothing to trigger a question. 
About 5-years ago I talked with GM reps at an NHRA nat'l event at Sears Point, Ca and asked directly whether the ZZ4 would pass the Cal tailpipe test. The first (younger) guy would not commit, but an older rep there overheard my question and the answer I got and stepped in. He said the ZZ4 will pass the Ca emissions tailpipe test
but had no EO#.The ZZ4 is essentially an L98 engine with a little bigger cam and slightly higher compression. There should be no problem with smog.
The ZZ4 does have aluminum heads and I believe the pre '87 L98's have cast iron. It would take a savvy smog tester to pick up on that since GM aluminum has been around now for nearly 20-years. This last year I asked a local smog station guy about what they look for during smogging. He said, speaking, for himself, as long as the visible parts say "GM" there is nothing to trigger a question.
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I would go with the ZZ4, and all the TPI components will transfer over. You may need to deal with some EGR issues being in California and having an 85 with internal EGR, but otherwise it should be a straight swap. (if it were in any other state, i'd say to delete it totally) I'd ditch the 85's heads altogether.
The cam is not that different in size from the stock, but it will need a custom retune. It will likely pass with the stock program though.
Note however, that the ZZ4 will not make its rated HP/TQ numbers once you put a TPI on it.
The cam is not that different in size from the stock, but it will need a custom retune. It will likely pass with the stock program though.
Note however, that the ZZ4 will not make its rated HP/TQ numbers once you put a TPI on it.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 195
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From: San Bernardino & Orange County CA
Thank you to all who have responded. Off to our annual Valentines weekend, but obviously with no Vette. I'll check back in next week for additional postings. The mechanic is too busy to work on the new engine stuff, probably 2-3 weeks before we start.
