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Need help making a decision

A

airbornesoldier327

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Alright heres my delima, i have been ordering all this stuff for my blazer, since im making so much more money over seas, and i want to make the blazer my daily driver as apposed to buying another vehicle and having a car payment again. Well i want to know if i should rebuild the motor i have in it and stroke it while im at it, or should i just order a crate motor? Also i the price on the crate motor, my buddy can order it for me for $1,200.00 and its rated at 300 HP. I have no idea what mine would come out to if i stroked it, nor do i have a clue where to take it to ahve it done. Im in the Fayetteville area in North Carolina, have any idea on how much it would cost to stroke the one i have, and if so where should i go to do it. Thanks for the input.
chris
 
Stroker

I recently talked with a very experienced engine builder about stroking my 350. To my surprize, he stated that the 350 bored and stroked out to a 383 has problems due to the increased arc of the crank and related geometry issues. I do have a 383 down in Mexico, but its a 8.0:1 compression ratio due to the crappy gas down there. I have had no problems, and like the motor fine, but its not a daily driver. That aside, building a stroker engine will be expensive compared to the crate 350. You can get the crate motor for around $1200, and with a waranty, its a great option for a daily driver.
 
383's with 5.7" rods have geometry problems because of the short rod ratio.........6.0" rods solve the problem :bow:
 
to give you some idea of engine shop machine prices I just spent $900.00 having my caddy 500 machined, the only new parts installed there were stainless valve guides, thats just machine work, crank grinding, bored the block and resurfaced the heads no new parts other than the valve guides, I'm still about $1500.00 shy on parts :doah: If your trying to save some cash go for the crate!
 
how does a 383 have a geometry problem? a 383 with 5.7 inch rods has better "geometry" than a 400 with 5.565 inch rods, but gm still built a ton of them.
350 rod/stroke ratio = 1.63
383 w 5.565 in rods = 1.484
383 w 5.7 rods = 1.52
400 rod stroke ratio = 1.484

ryan
 
It's not really a geometry problem Ryan, but a 383 stroker with 5.7" rods has a poor rod ratio and as a result will not tolerate high rpm's (over 5500), on the same note it's purpose built to make power down low where most 4x4's need it.
We've had this rod ratio discussion before and i have spoken my peace about using 6.0" rods and raised ring pistons with a 3.75" stroke crank in a 350 block which produces a 1.6:1 rod ratio and is very similar to a stock 350 rod ratio which is 1.64:1
The higher rod ratio provided by the 6.0" rods let the motor rev freely to 6500 rpm and the extra cid provided by the longer stroke produce an additional 35 ft lbs of torque.
As a added benefit a 6.0" rod 383 will last must longer than a 5.7" rod 383 because there is dramatically less rod angularity, piston scuffing, cylinder bore wear and friction when the piston is just BBDC and ABDC.
Well ther you have it Ryan22e.......i guess the 383 with 5.7" rods could use some geometry lessons :bow:
 
A longer rod tends to produce a flatter torque curve, but has little to zero effect on the torque peak.

Something my former employer racing engine shop told me is that the ideal rod ratio depends on the application. A long rod is NOT always better. For a circle track or road race car you would want the long rod as it makes the car easier to drive (harder to be in the wrong gear). For a workhorse truck engine a shorter rod will reduce piston dwell at TDC which reduces the tendency to detonate. So everything else being the same, a short rod engine can survive on lower octane fuel.

Had a look to see what GM does with their Crate strokers. Compared the ZZ385 to the HT383. Rods and pistons are both radically different p/n's, but no mention of the lengths. Looked up the HT's rod p/n as a service part and it is a 5.7" rod. Took a little more doing to find the spec, but the ZZ's rods are also a 5.7" rod.

Back to the original question though. Do you have a local quality machine shop that you trust? If so, they can very likely build you something better for the same cash. If you don't, or do not have the time to work with the shop then a crate engine makes more sense.
 
Alright, well it soundslike its settled then, im going to go with the crate motor, where woudl i find this $1,200.00 crate motor at? Also whats the horse poser rating on it? alright, thanks for shedding some light on the subject!
 
Here's one place that has a good listing of the motors.

From what I've heard/seen, most dealers will sell crate engines at about the same cost as any of the online places. If you get a part number online though, you can contact a local dealer and ask pretty easily.
 
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