302 Rebuild or Crate Motor

Whassup everyone? I am a newbie to this site, I have read threw many of other posts on here about almost the same dilemma I have. I have a 91GT with only a 105k on it and I believe one of the bearings is bad since the whining sounds comes from the main pulley which sounds like a I strapped a cat to it, when it warms up the sounds goes away but I get a major power loss after 3500 RPM. I decided to stick with 302 so I don’t have to change too much on the car, plus I would like to get a SC down the road. I was looking for some input on weather I should rebuild this motor or get a GT40 crate motor I found on the web that has:

compression ratio: 9.0 to 1
crankshaft: Nodular iron, 3.000" stroke
head, chamber size: GT-40 aluminum heads, 64cc
valve sizes (i/e): 1.940" / 1.540"
camshaft: B303, hydraulic, roller
camshaft lift (i/e): 0.480" / 0.480" hydraulic
cam duration (i/e): 224 / 224 degrees @ 0.050 lift

If I do go the GT40 crate motor route what would stock parts should I change to not have problems? I am already planning on replacing intake, injectors, radiator, ignition box, and getting a chip. The only thing I have on it our some Mac shorty headers and a Edelbrock 65mm TB. Any feedback you guys may have I would greatly appreciate it.

Thank you,
Jared
 
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2 things to think about.....

1.) A rebuild will cost just as much as a crate motor to have a local shop do it for you once you factor in all the labor and other charges. Unless you do the majority of the work yourself you will spend the same amount of money either way.

2.) If you build it yourself, you can upsize it with the money you save. 331 or 347 stroker kits can be bought for as little as $700-$800 with hypereutectic pistons. Only $1000-$1200 with forged pistons.
 
another vote against the crate motor. you never said exactly what your plans forthe car were. it is obvious that he cant build the motor himself. if you will get on the regional section, you will likely find someone that is willing to help you do the labor (cheap or free). i know that i am always willing to help anyone in my area. that is part of being a community...right?

if you dont want to spend alot of money. rering your motor(91s had forged pistons). get in touch with thumper get those E7s ported. a good intake and spray with a 100 or 150 shot. along with a good suspension you should get some pretty good times. and you could always some back later and 6psi blow it, drop the nozzle size back to 40hp(for intercooled affect only) and kick some ass. i think all that adds up. just depends on what kind of cash you really want to spend, do you drive it everyday?
 
Thanks for all your feedback everyone. So what is better to get a 331 stroker kit or a 347, is bigger always better? I see they cost about the same. Your thoughts? My plans for this car is to smoke camero's and firechickens, lol. I love the car so I want to fix it up and maybe drive it to work about 1 day a week and maybe a couple times on the weekends. I do not drive the car easy so thats most likely why I only got 100k out of the motor.

Thanks,
 
there was oil issues with strokers backin the day but they all corrected that now so i say go for 347 stroker and use forged internals so you have room to grow do this once and do it right so in the future you wont be tearing the motor down again
 
A 347 will have a bit more torque production potential. More cubes = more low-end torque.

A 331 will be more reliable at high-RPM operation. Smaller stroke = less rotating mass.

For a street machine, I'd go with a 347. If you're going to throw on a blower, get forged internals, and make sure your compression isn't too high.
 
shorty1993 said:
another vote against the crate motor. you never said exactly what your plans forthe car were. it is obvious that he cant build the motor himself. if you will get on the regional section, you will likely find someone that is willing to help you do the labor (cheap or free). i know that i am always willing to help anyone in my area. that is part of being a community...right?

if you dont want to spend alot of money. rering your motor(91s had forged pistons). get in touch with thumper get those E7s ported. a good intake and spray with a 100 or 150 shot. along with a good suspension you should get some pretty good times. and you could always some back later and 6psi blow it, drop the nozzle size back to 40hp(for intercooled affect only) and kick some ass. i think all that adds up. just depends on what kind of cash you really want to spend, do you drive it everyday?

91's have forged pistons?
 
hyper pistons came out actually in late 92. for all intents and purposes, people say 93 and that is about right.
 
another vote against the crate motors. they are over rated in hp and inflated in price. if you look around the classifieds you could build the same crate engine even with a few used parts for alot less.

the big cost of having someone do it is that the removal and replacement of the engine is most shops is an automatic 1500 (750 + 750). If you only wanted to build a good reliable engine and keep most of your stock parts then upgrade with time, you could do it relatively cheap. even with going with good forged parts. I 2nd the "pm rick91gt" advice. great guy and he will be very honest with you as well as give you advice and information, whether or not you go with him.

having said that the 331 or 347 would both be a great motor. I am kinda partial to the 331 though.