2 or 4 bolt main motor?
#1
2 or 4 bolt main motor?
I have a 89 iroc Z 5.7 tpi 700 trans,all stock.Were the 350 blocks 2 or 4 bolt mains,and is there anyway to tell with the motor in the car?I cant get to the casting # there's too much in the way.
#2
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: 2 or 4 bolt main motor?
if its stock, 99% sure its a 2 bolt, if you cant get to the numbers, the only way to know is to pull of the oil pan, not a easy thing to do in the car
#3
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Re: 2 or 4 bolt main motor?
I wouldn't lose sleep over it either way. If it's just for bragging rights, call it a 4 bolt and leave it at that.
#4
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Car: 1991 Z28 1LE
Engine: 370CID GenIII
Transmission: 4l60e
Axle/Gears: 4.33 Moser 9inch
Re: 2 or 4 bolt main motor?
my 89 iroc had a 4 bolt block in it, but it was rebuilt so i dont know if it was the original motor or not, the only real way to know is to pull it out and check cause even if u have the block number it usually says 2 or 4 bolt on the discription.....y do u ask it doesnt make it more powerful or anythin....
#5
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Re: 2 or 4 bolt main motor?
"Officially", all iron head L98 motors were two bolt, and alum. head L98 were 4 bolt. I've never seen any documentation showing otherwise.
un"Officially" several people have reported their iron head L98 motor's have had 4 bolt mains. This isn't too surprising actually. It's GM afterall.
un"Officially" several people have reported their iron head L98 motor's have had 4 bolt mains. This isn't too surprising actually. It's GM afterall.
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Car: 86 z28 LG4 305ci
Engine: LG4 305ci
Transmission: 700r4
Re: 2 or 4 bolt main motor?
Yeah, who cares. Its stock. So much other crap will fail around the mains before its ever time to address them. The 4 bolts are just holding the crank in place if **** gets hecktic which it basically will never do witha stock engine. My CK1500 has two bolt main with headers, and exhaust, plust I floor it as much as possible.
#7
Re: 2 or 4 bolt main motor?
Just wanted to thank evryone for the info,the reason I was wanting to know ,I'am gonna drop a 383 with a carb in it and a friend of mine wants to buy the motor.I know that a 2 bolt's not gonna hurt anything ,but he's 17 and everything's gotta be a 4 bolt.
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Car: '98 Mustang GT
Engine: '03 4.6L
Transmission: T45
Axle/Gears: DK
Re: 2 or 4 bolt main motor?
Maybe the one that matches up to his block number doesn't say 2 or 4 bolt. I would rather him do a simple check on the numbers vs. pulling an oil pan. If it were my car/engine, I would want to know the numbers regardless.
#12
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Car: 1991 Z28 1LE
Engine: 370CID GenIII
Transmission: 4l60e
Axle/Gears: 4.33 Moser 9inch
Re: 2 or 4 bolt main motor?
im just stating there is only one way to be sure and that is to pull the pan, if hes gonna build a 383 hell have to pull the pan too, i doubt he has one of the rare blocks that are listed as 4 bolt only.....ive had countless 350 blocks and everytime i run the number it says 2 or 4 bolt mains....i just use the mortec info now to identify the stock cid of a block....its a 2 part process in my opinion, look at number then pull the pan, 1 with out the other is only a half truth....
#14
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Car: '98 Mustang GT
Engine: '03 4.6L
Transmission: T45
Axle/Gears: DK
Re: 2 or 4 bolt main motor?
My buddy picked me up a 350 motor, I checked the numbers and then pulled the pan to verify. Turned out to be a 4 bolt. He later told me it was out of a Chevy bus.
#15
Re: 2 or 4 bolt main motor?
I appreciate all the feedback,what you guys are saying I understand,The 383 I'am building is on a 70's block as a foundation.The motor in the car is gonna get sold,I can't get to the casting #'s with it in the car.I'am just new to the third gen thing.This is my first project thats younger than I am, and plans are already in the works for a whole boatload o mods.
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