Looking into complete motor rebuild/ performance upgrading.... HELP
Login  | |
|
Looking into complete motor rebuild/ performance upgrad... - 4/26/2008 8:42:00 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
So as many of you know, my cherry '89 has a rod bearing problem, and i think I have decided to just do the rebuild myself. I found a motor for cheap, but it has high miles and i dont want to have to do this all over again so i think a rebuild (done right) is the best way to go. SOOO a have a few questions for all of you MASTERS...
I have about $1000 to work with, and i will be doing the R&R myself. Time is really no issue as i have been riding my motorcycle (thank god/ prey it doesnt have problems).
So i really need some input on what parts to use. I want to get a nice performance increase, and still get another 100K out of it. I havnt really looked into any of this, so if you guiys could just throw some reccomendations out there that would be great. So far I plan on doing a mild bore, w/ oversized pistons, and maybe a mild cam. What else can be done on these 4.3's internally that i wont have to reprogram the computer for, and thats not too wild?
Heads? crank? etc, etc help me out guys...
Thanks
_____________________________
Dan
|
|
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 3:03:08 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
can anyone help me out on this???
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 3:32:36 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
Wow... Well, I had thought out a nice response to this as I read it and did not have time for a response right then. Now I have completely lost my train of thought due to the unnecessary bumping of this post... I'll have to retrace my thoughts when I have some time in the hopefully near future...
*EDIT*
I will ask for a few things... Budget? Expectations? Experience level (ie. what you are comfortable doing)?
< Message edited by swartlkk -- 4/27/2008 3:45:24 PM >
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 4:14:24 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Thanks i appreciate it swartlkk....
Budget: around $1000
Expectations: To have a completely "new" motor... like it came from the factory, but with maybe 25-50 hp increase
Experience: done numerous motorcycle rebuilds... never an automobile. Time is not an issue, and i'll have the help of my neighbor who is a mechanic when needed. I'm gonna have to sub out the machine work, but everything else i can do.
I guess i need some guidance on what to go through when I'm in there... any trouble spots on these things? Also need some guidance on where to go as far as parts... kit/indv. parts.
I have a feeling Im gonna need to have my crank redone, and i dont want the bearings to go again... = oversize? Heads? Cam? etc etc
As you can see, i'm pretty lost on the parts aspect. I know that i want to do 30 over bore, and aftermarket headers/ full exhaust. Will this get me the performance increase im after?
Otherwise id like it to be as reliable as a brand new motor.... I guess I have high expectations, but i just want to make sure i do this RIGHT so i wont have to worry about it again.
Any help is much appreciated!
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:03:28 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
A budget of $1000 should be easy to work with.
For an overview, you will need new pistons (due to the 0.030" overbore if you go that route), rings, main/rod bearings, new cam bearings (if you choose to - I would recommend they be replaced), at the least a polish job on the crank journals, the bore on the cylinders, etc (for the stuff I probably left out).
Ok, onto the work you need a machine shop for. The boring of the cylinders requires the expertise of a machine shop. You will have the shop bore the block, check for a flat deck (head mating surface), and install the new cam bearings (if you choose). You can also have the shop rebuild the heads for you if you choose. They should be checking the flatness, doing a valve job (which will re-cut the valve sealing surfaces), install new guides (if necessary), lap the valves to a perfect seal, and install new valve seals.
Then there is the crank. You really have to determine if the crank is salvagable first by inspecting the journal that was affected by the lost bearing. If the journal can be cut down, you have a choice to make. Cut one journal and only get one oversized bearing for that journal, or cut them all to keep them uniform. If it were me, I would try to source a used, but good crank that would just require some polishing and install stock bearings. With the "split pin" design of the crank in these engines, it is quite difficult to cut a journal properly.
As far as performance goes, I would highly recommend an aftermarket cam be added to the mix (pretty much requiring new cam bearings). However, this might bust the budget as new lifters should also be installed. A full cam/lifters kit should be available from places like Summit Racing or Jegs.
Sorry this seems short, but I just realized what time it was... This article - 3/4 350 should shed some light on some things that can be done. As the article suggests, the cam is the biggest expense in the build, but is key in making power! Here is another thread posted by another member - CLICK HERE - may help some as well.
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:28:51 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Thanks for the reply man... Il have to call some shops to see what they want for the bore, valve job, and possibly crank polishing. Then Hopefully i'll have enough to go with header/ exhaust and cam kit.
Couple question:
1. What is a good brand piston? Ive always used weisco on my bikes, but have no idea with these...
2. What all gaskets are nessesary for the job? Again, can you suggest a good brand?
3. What about valvetrain? Does it need to be replaced as well?
Thanks for all the help!
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:31:45 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
Since you aren't going to be testing the strength of the piston (ie. not huge power numbers), anything will do. Just go for a master rebuild kit that gives you the option of larger pistons, rings, and oversized bearings.
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:41:29 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Somthing like this
What about the valves, valve springs, pushrods, etc etc???
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:48:02 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
That set would do nicely provided your rod journals did not change... The valve seals are included in that kit. The push rods can be reused as can the valve springs. You would still need to assess the condition of the valve guides (disassemble the heads and feel for play in the guide).
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:50:24 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Okay thats good to know... How do the quality of those kits compare to oem?
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:57:00 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
All of those components will probably exceed the OE stuff.
If you weren't doing the overbore (you don't really need to), you could save some money there both in machine shop costs and pistons.
You could just have the ridge removed from the top of the cylinder bore and then have the bores honed and reinstall your pistons.
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 5:59:24 PM
|
|
|
mr.vls
Posts: 94
Joined: 4/2/2008
Status: offline
|
eddlebrock makes a cam and intake manifold set for the 4.3 but I am not sure if it would fit in your budget.
_____________________________
1989 S15 Jimmy (DD) with 388K Miles, GM Factory Rebuilt Engine/Tras. New Paint, Headliner, all Suspension Bushings, Eddlebrock Waterpump/Shocks, Pioneer Head Unit/Speakers. Vehical is in Great Shape. Original Owner.
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 6:01:41 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Would i see any power increase from an overbore? I think the kits are the same price for the standard pistons though...
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 6:03:39 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
But you wouldn't need to replace the pistons if you were to stay with the stock bore and just clean them up and re-ring them.
On adding power... Well, yes and no... If I had to choose, I would get an aftermarket cam over a bore job. If you were to bore and offset grind the crank to increase the stroke, then you would notice the increase, but I would say that the increase will be so minimal that you probably wouldn't notice it.
< Message edited by swartlkk -- 4/27/2008 6:12:57 PM >
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 6:10:17 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
I'll take that into account... I'll have to really dig into this soon and find out whats needed. But my overall goal is to restore the engine to new... THEN worry about performance. I think a cam kight be the way to go. How much increase would you expect to see with a cam and headers/ex.???
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 6:32:54 PM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
I'm partial to Comp-Cams and the 270HR should provide a good kick in the pants. The kit linked to provides the cam, lifters, valves, retainers, and locks. If you didn't want to chip the computer, the 266AHR will provide a good increase while keeping the stock tuning. I would not hesitate to contact Comp Cams and talk with a representative. In my past experiences with their tech support, I have been very satisfied with the knowledge and help they have been able to provide.
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/27/2008 6:42:32 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
WOW.. thats expensive... I was thinking about somthing more along these lines
http://store.summitracing.com/partdetail.asp?part=CCA%2DK18%2D124%2D4&autoview=sku
Sorry... one more question;
Will I sacrifice any reliability by reusing the pistons?
Thanks for all the help!
< Message edited by dbleon -- 4/27/2008 6:58:45 PM >
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/28/2008 4:03:59 AM
|
|
|
swartlkk
Posts: 14299
Joined: 5/1/2005
From: Waterloo, NY
Status: offline
|
No, so long as the pistons are not scored badly or otherwise damaged, you won't be compromising the life expectancy of the engine. You'll basically have to get everything apart inorder to assess the condition of the components before ordering anything. You probably will want to have everything back from the machine shop before ordering to know what you are working with.
You could go with the 268H kit, but it may not like being used with the stock torque converter. This cam is suggested for non-computer controlled, higher stall, and lower gears. Again, you really should contact Comp Cams tech line and have a talk with them. They talk with people everyday that are looking for advice on what cam to install provided with the expectations of the customer.
_____________________________
Kyle-
2004 Rainier
1970 Chevelle - Resto
1974 K5 Blazer - Resto
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 4/28/2008 9:11:53 AM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
Thanks alot kyle... really appreciate the help. Im gonna hopefull get everything torn down this weekend and see where im at. Maybe for performance i'll just stick with the exhaust/headers cause the cam kita are pretty darn expensive.
Thanks again!!!
_____________________________
Dan
|
|
|
|
|
RE: Looking into complete motor rebuild/ performance up... - 5/2/2008 2:42:13 PM
|
|
|
dbleon
Posts: 319
Joined: 8/31/2007
Status: offline
|
So i called a few machine shops in the area and they all want around $1000 JUST for the machine work!!!! That seems outragous to me!!! I was so pissed.... Even if i bought all the parts, and installed it myself it wouls still cost around $1500 total.... SOOOO i called one of the most reputable engine builders in AZ, about 150 miles away from my home, and they told me that they could drop a new motor in with EVERYTHIG redone for ~$1800 out the door. There is no core charge, no other costs, thats after tax and everything. Thats seems decent considering all the work i would have to do to save 300 bucks... Here is a list of what they do.
Reman block 10-20 over
cleavite pistons, rings, mains, rods, timing, lifters, oil pump, all bearings, crank recconditioned, reman heads on new valvetrain, new cam, im probably forgetting something too. Oh quality gaskets too.
They urge their customers to come watch the engined being built, and see their operation.
Turn around time is 5-7 days. Warrantee is 5 years 100k miles on everything.
What do you guys think??? Go for it??? Id have to take out a loan to do it, but ...
_____________________________
Dan
|
|
|
|
 Today's Posts
Most Active Topics
Make A Donation
Forum Rules & FAQ
RSS Feeds
Chevy Blazer Prices
Chevy Blazer
Trailblazer SS
Advertising Info
|
Blazer Forum .com is not affiliated with or endorsed by Chevrolet Motors Division or General Motors.
|
Printable Version
