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engine build 350 or 383?

Where are all of your getting your chips burned?

I recently rebuilt my TBI 350 which came out of a 87 blazer.
I installed
Double roller timming chain
flat top pistons
crane cam
roller rockers

I've got 35" tires 4.56 gears and a new 700r4 tranny

I'm ready to sell the turd because it does not have enough power. I have a 4k lb boat that I want to be able to tow. There is a highway hill that I have to go up to make it home. I have to drop the thing into 2nd and floor the damn thing just to make it up at 50mph and even then it is struggling.

My Range Rover I can pull up the hill at 70 or more. I'm desperate, I would love to keep the truck but the power is unacceptible. Any suggestions? Keep in mind I have to pass smog test.

Dood. Dont call your truck a turd. I have been telling you that your motor is a horrible mismatch from the start . Go back and read your roller rocker thread you started a while back.http://coloradok5.com/forums/showthread.php?t=234562&highlight=roller+rockers I tried to tell you then that your combo wont work.

Just for compairison. I have a mild build TBI 350. I can pull my 17 foot IO ski /fish boat over our local 8600 ft elevation mountains at 65 mph no problem.
 
If you feel the motor is gutless, why on earth would you eliminate headers from consideration?

Because I dont want to deal with them plenty of vehicles get by without headers. If you ran straight pipes no muffler/No cat you would probably get even more HP. It's just a matter of choice I dont want them.

Thunder said:
I have been telling you that your motor is a horrible mismatch from the start .
Name one thing that is incompatible. High compression does not necissarly require more fuel. I don't know why you think it does. High compression does not change the air fuel ratio.Only an increase in the volume of air will change the air fuel ratio. My stock TBI should be more then enough to supply the fuel I need. In fact it smells as if it is running a little rich, that I do need to figure out. My motor does not ping it runs fine. The cam is a mild cam which I should find out what it is today and the roller rocker are the same as the stock rockers they replaced. So the only thing functionally different I have in my motor is cam and flat top pistons.

5.7L and 210hp is a TURD sorry its just fricken rediculous. It amazes me that GM wonders why they are in the tank they have been producing turds for a long time now. I just look at other cars I own 290hp out of a 3.2L V6 and 320hp out of a 4.4L V8 and its just very dissapointing.

I'm sure I could tow a 17 foot boat at 65 also. My boat is 21ft and over 4000 lbs. I look at the money I have into this thing around $4k (including the price of the truck) and I look at what I can get for $4k and I think I made the wrong choice. This one is up on craigs list for what I have into it. Unless I can figure out how to get some decent power out of this thing soon it will stay there. I honestly would love to keep this thing and be happy with it. I'm just not sure it will be able to produce enough power to fit my needs.
 
To everyone thanks for the help in deciding which motor to build, I am going with a 350. Now the parts. I have been doing some research after reading all the posts and I think I come up with what I am looking for, tell me if any of this should not be put together, or if the combo will work the way it should. Eagle cast steel crank, Edelbrock performer-plus cam, Eagle "sir" I beam connecting rods, Speed Pro cast pistons, Federal Mogul OE rings, and for now stock-rebuilt heads, Edelbrock Performer intake, not sure on the Carb yet. Headers shortly, prefer long tube. Once money has been put back, a set of Edelbrock Performer Heads.

Like I said, new to this so any advice would be much appreciated from anyone.
 
I'll let Scott talk about the in-depth of your parts choices, but it would seem to me that a good core would have rods and a crank that are PLENTY good for a "mild" 350 build.

IMO, if buying a core motor, get one that already has a roller cam in it. Cars from the late 80's up, and trucks from '96 up. Car motors are almost universally 2 bolts (maybe Corvettes weren't?) and even the '96+ truck motors weren't all 4 bolts. The number of main cap bolts is again a personal preference deal, and should have no bearing on a build such as you mention. Problem with '96+ truck motors is that they aren't drilled for the fuel pump.

Get hyper-eutectic pistons.

Don't lust after the Edelbrock heads, from what I've seen, Edelbrock heads are left in the dust when there are competing brands, which is a given with a SBC.
 
Sounds like you're going to stay with a carb? Also if you're not looking to spend a bunch of money right away give me the combustion chamber size of the heads you're going to run then i can suggest some parts for you. Keep this in mind, power and torque are made in the cam and head selection for the most part. You get what you pay for. I'm a tried and true believer in AFR heads since i've personally ran them on two of my engines now and i've seen the difference they make. Yes they aren't cheap but making torque and HP isn't cheap. Also most people are talked into the hype of bigger is always better and for a truck this isn't the case at all.
 
I am sticking with a carb for now. School teachers don't make much, so EFI has to wait for a while down the road. I am not sure what cc the heads are that was on the motor, can find out from the machinist on Monday. Probably purchase 64cc down the road, if I have read everything correct that will help keep comression ratio moderate. Want to run pump gas.

Sticking with Edelbrock is certainly not a have to. Just easier to find combinations with their info.
 
I ran a mild 350 with the Edelbrock power package and stock TBI. I had great low end but seemed to really choke at higher rpm and I wouldnt recommend it as a long term thing.
 
I checked with the machinist and from the serial numbers they are 75 cc stock heads. Serial # is 3998991. One of my heads was no good so I need to find another one with matching #. I found one at the local wrecking yard, the only difference was in the center of my head it says GM 68, the junk yard head says GM 62. Does this make any difference. Also, they had a few heads that the # was 3998993. Doing research on numbers, the cc's are the same, they just came off a truck. Will the 993 work?

Decided to go with a Comp 4x4 cam. I all ready have the Edelbrock intake from the motor that was in the Blazer. My machinist is telling me that the block is at 30 thousands now, and can be honed to 40. Should I just have him bore it 60 over and know that I have a true sizing instead of just honing. It is a 76' according to the VIN number on the block.
 
The "991" heads IIRC are GM target master engine heads and are thick casting heads. I would try to find a replacement and keep them. The only number that metters is the "991".

As for the cylinders needing honed to .040" i would do that rather than going to .060". Honing to size is done when there is little material to remove rather than boring and the cylinders will be just as straight and accurate as if they were bored.
 
Thanks so much. I will go back and pick up the head tomorrow and hopefully get this build underway. Bow season is fast approaching.
 
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