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351 install questions.....

  • Thread starter Thread starter 85GTlover
  • Start date Start date Jun 13, 2004
8

85GTlover

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Mar 20, 2004
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Jun 13, 2004
#1
  • Jun 13, 2004
  • #1
What would I need to do to install this engine in my 85gt?
I have a chance to pick up a "modified" 351, for very cheap, complete with an engine stand. I have yet to see the motor what should I look for? What years are better etc or #'s would be ideal? Will a stock T5 bolt right up? Would it be a big difference over my basically stock 210 hp motor? What is a running carbed 351 worth?

Any info would be greatly appreciated.
 

hllon4whls

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Jun 13, 2004
#2
  • Jun 13, 2004
  • #2
A modified 351 was some that came in trucks and some cars in the late 70's. It is about 160 hp. It has cast pistons, a smog flat tappet cam and wheezer heads.

You will notice a big difference when you swap it in your car. It will be bigger, heaver and a whole lot slower.

Any engine can be built to run, but be aware that there are not a whole lot of parts for these engines. If you want the most versitile 351, you want a windsor. This is the motor that shares the heads, wp, cam, etc with the 351.
 

SLiM JiM 156

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Mar 18, 2002
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Rohnert Park, CA
Jun 13, 2004
#3
  • Jun 13, 2004
  • #3
hllon4whls said:
A modified 351 was some that came in trucks and some cars in the late 70's. It is about 160 hp. It has cast pistons, a smog flat tappet cam and wheezer heads.

You will notice a big difference when you swap it in your car. It will be bigger, heaver and a whole lot slower.

Any engine can be built to run, but be aware that there are not a whole lot of parts for these engines. If you want the most versitile 351, you want a windsor. This is the motor that shares the heads, wp, cam, etc with the 351.
Click to expand...

couldnt have said it better myself!
 
8

85GTlover

New Member
Mar 20, 2004
704
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0
Jun 13, 2004
#4
  • Jun 13, 2004
  • #4
hllon4whls said:
A modified 351 was some that came in trucks and some cars in the late 70's. It is about 160 hp. It has cast pistons, a smog flat tappet cam and wheezer heads.

You will notice a big difference when you swap it in your car. It will be bigger, heaver and a whole lot slower.

Any engine can be built to run, but be aware that there are not a whole lot of parts for these engines. If you want the most versitile 351, you want a windsor. This is the motor that shares the heads, wp, cam, etc with the 351.
Click to expand...



Well that takes the fun out of my day, I thought I was getting a steal....but $175 for that and an engine stand is still cheap.....so I would be better off building my 210hp 302 obviously, thanks for the quick, insightful, honest, educated response, much appreciated.
 
8

85stangt

Founding Member
Sep 11, 2002
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byron, il
Jun 13, 2004
#5
  • Jun 13, 2004
  • #5
ok i think u guys are missing a very important point--in my opinion the 351 block is fundamentaly superior to the 302 b--dont get me wrong i still love 302s--but the deck height on a 302 is...correct me if im wrong but 8.2 in.--the 351 is either 9.2 or 9.5 --u have that much more room for a long stroke, i have never personaly reworked a 351, but i plan to, i mean if your going to rebuild the 351 ...say a 393 stroker kit, average heads,cam,intake
maybe a 750cfm, reasonable 10:1 comp.--- ill take a wild guess that you would have a very reliable say 300 to 400 hp NA(and that may even be underating)---plus ive read that a 393 has a big block persona--either or, I just thought id jump in and ramble off a few things--
 

hllon4whls

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Jun 14, 2004
#6
  • Jun 14, 2004
  • #6
85stangt said:
ok i think u guys are missing a very important point--in my opinion the 351 block is fundamentaly superior to the 302 b--dont get me wrong i still love 302s--but the deck height on a 302 is...correct me if im wrong but 8.2 in.--the 351 is either 9.2 or 9.5 --u have that much more room for a long stroke, i have never personaly reworked a 351, but i plan to, i mean if your going to rebuild the 351 ...say a 393 stroker kit, average heads,cam,intake
maybe a 750cfm, reasonable 10:1 comp.--- ill take a wild guess that you would have a very reliable say 300 to 400 hp NA(and that may even be underating)---plus ive read that a 393 has a big block persona--either or, I just thought id jump in and ramble off a few things--
Click to expand...

What you said is true. But there are no aftermarket heads for a modified that I am aware of. I am sure that cleavand heads can work, but you have to find a set. There are not as many stroker kits available for the modified or cleavland design, so you have to work with what is out there.

Now if he had a 351 windsor, I'd be hell yeah build a 408. Unless he wants something challenging and unique, I'd still reccomend staying away from the modified.
 

hllon4whls

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#7
  • Jun 14, 2004
  • #7
I found this on ebay. It has some great pics of a 351M head. Notice the canted valves. Also notice that there are no water passages in the side of the head. The water pumps pumps throught he bottom of the head through the block, unlike a 302/351W.

http://cgi.ebay.com/ebaymotors/ws/e...tegory=33617&item=7905510295#ebayphotohosting

Compare that to the 302/351 head below.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7905510400&category=33617
 
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