Swapping a 350 5.7 From a Suburban..?
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Car: 1988 Iroc-z28
Engine: 5.7 350
Transmission: 700R4
Axle/Gears: 2.77
Swapping a 350 5.7 From a Suburban..?
The Maro needs a new engine, so one of my friends said that his buddy has a 350 vortec engine out of a 93 Suburban that he would swap for me. is this a good idea?
I have an 88 IROC-Z28. It's not a matching numbers car. Would there be any proformance gains to this, and would I have the same amount of resources for go fast parts that I did with the original engine?
Thanks guys. =)
I have an 88 IROC-Z28. It's not a matching numbers car. Would there be any proformance gains to this, and would I have the same amount of resources for go fast parts that I did with the original engine?
Thanks guys. =)
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: Swapping a 350 5.7 From a Suburban..?
1.) A 93 350 is an LO5 TBI engine, not a vortec. Just because it has centerbolt valve covers doesn't make it a vortec. Vortech was available first in 96 or 97, I think. I have the LO5 in a 93 Chevy truck; it's okay, but your TPI 305 is more powerful now. If you take this engine, you need to check for a roller cam (it may not be roller and you'll need to do a few mods to make it accept the roller cam) and GET RID OF THE HEADS! Re-using your 305 TPI heads will work great!
2.) All the same resources/go fast parts will apply
Good Luck!
2.) All the same resources/go fast parts will apply
Good Luck!
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Car: 1988 Iroc-z28
Engine: 5.7 350
Transmission: 700R4
Axle/Gears: 2.77
Re: Swapping a 350 5.7 From a Suburban..?
1.) A 93 350 is an LO5 TBI engine, not a vortec. Just because it has centerbolt valve covers doesn't make it a vortec. Vortech was available first in 96 or 97, I think. I have the LO5 in a 93 Chevy truck; it's okay, but your TPI 305 is more powerful now. If you take this engine, you need to check for a roller cam (it may not be roller and you'll need to do a few mods to make it accept the roller cam) and GET RID OF THE HEADS! Re-using your 305 TPI heads will work great!
2.) All the same resources/go fast parts will apply
Good Luck!
2.) All the same resources/go fast parts will apply
Good Luck!
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: Swapping a 350 5.7 From a Suburban..?
There's no such thing as a vortech TPI unless you bought a scoggin-dickey TPI base that fits the vortech heads.
The vortech engine has basically the same block as the TPI 350 (L98) used until 92. The heads are completely different and were never available in anything other than a truck. You can tell easily by how the intake bolts on. The bolts at the front and back will be normal around the water ports but the center intake bolts will be basically straight up and down. Your TPI would not be like this.
The vortech engine has basically the same block as the TPI 350 (L98) used until 92. The heads are completely different and were never available in anything other than a truck. You can tell easily by how the intake bolts on. The bolts at the front and back will be normal around the water ports but the center intake bolts will be basically straight up and down. Your TPI would not be like this.
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Car: 1988 Iroc-z28
Engine: 5.7 350
Transmission: 700R4
Axle/Gears: 2.77
Re: Swapping a 350 5.7 From a Suburban..?
Thanks for answering so many of my questions. I really appreciate it. Is this an upgrade or a downgrade from a rebuilt 350?
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Because of the heads, it's a downgrade.
The shortblock may even be a downgrade, because it most likely isn't set up for roller lifters.
The shortblock may even be a downgrade, because it most likely isn't set up for roller lifters.
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Car: 1988 Iroc-z28
Engine: 5.7 350
Transmission: 700R4
Axle/Gears: 2.77
Re: Swapping a 350 5.7 From a Suburban..?
Well my car has probably over 200k on it and fails smog like a cigarette. is it still a bad idea. how much would it take to get my engine rebuilt you think?
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Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
Re: Swapping a 350 5.7 From a Suburban..?
If I were you, this is what I would buy:
http://www.sdparts.com/product/12556...eAssembly.aspx
So that's under 1300 bucks. Now, you need the rest.
If you have TPI, re-use your heads. Rebuild them and make sure you've got big intake valves (1.94 or 2.02)
Use either an L98 or LT1 cam (used of course) and re-use your roller lifters.
Bolt on the rest of your old parts and run, run, run!
That's just what I would do if I were you. If I were ME, well.....
you don't want to go there!
Good luck!
http://www.sdparts.com/product/12556...eAssembly.aspx
So that's under 1300 bucks. Now, you need the rest.
If you have TPI, re-use your heads. Rebuild them and make sure you've got big intake valves (1.94 or 2.02)
Use either an L98 or LT1 cam (used of course) and re-use your roller lifters.
Bolt on the rest of your old parts and run, run, run!
That's just what I would do if I were you. If I were ME, well.....
you don't want to go there!
Good luck!
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
There's no such thing as a vortech TPI unless you bought a scoggin-dickey TPI base that fits the vortech heads.
The vortech engine has basically the same block as the TPI 350 (L98) used until 92. The heads are completely different and were never available in anything other than a truck. You can tell easily by how the intake bolts on. The bolts at the front and back will be normal around the water ports but the center intake bolts will be basically straight up and down. Your TPI would not be like this.
The vortech engine has basically the same block as the TPI 350 (L98) used until 92. The heads are completely different and were never available in anything other than a truck. You can tell easily by how the intake bolts on. The bolts at the front and back will be normal around the water ports but the center intake bolts will be basically straight up and down. Your TPI would not be like this.
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The '93 shortblock probably isn't a bad start - depending upon how it was maintained. My brother has a '93 C1500 that wasn't all that well maintained, he put a lot of miles on it but ended up needing a rebuild. Similarly, another brother has a '94 Suburban that looks good on the outside, but engine maintenance was neglected, and we'll be putting a rebuilt in it for him next month.
As already stated, your original 305 TPI heads were better than the '93 truck heads, but what you do about that depends upon your goals and actual emissions requirements. Generally speaking, a Vortec-headed 3rd gen controlled engine, or an LO5 headed 3rd gen controlled engine, will pass emissions sniffer, but you could get into "issues" with visual inspection.
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Car: 1988 Iroc-z28
Engine: 5.7 350
Transmission: 700R4
Axle/Gears: 2.77
Re: Swapping a 350 5.7 From a Suburban..?
I have a 350 so I don't have 305 heads. do it? I havn't gotten word on the engine so I'm thinking I may just go new. How much should a shop charge to take out and put the new engine in? should I do it?
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