What do I do? Build a new motor?

[JSM]

Ok here is the background and the truck.

http://videos.streetfire.net/video/Life-of-92-GMC-Typhoon_165068.htm

Truck is running good, working through bugs as I get time/motivation.

The base engine is left over from a 67 camaro I owned at one time. It was never built for boost or even this much power, but I had it laying around and had to use it for something besides a dust magnet.

So now that it is running I am honestly happy (for now, I am sure that will change) with the amount of power it is making, how it drives and just generally the truck is fun to drive and with the AWD would probably stomp most cars on the street. It was never built as a race car anyways.

Motor currently is
350 bored .040
Manley forged pistons
stock rods (beamed, polished, etc.)
stock crank
total seal rings
041 casting heads with 2.02/1.6 SS valves
full roller rockers
hyd. camshaft
~9.7:1 CR
Twin GT35 turbos running 7psi (wouldnt' mind moving up to 10 at some point).
ARP head bolts, main studs (2 bolt stock caps)

Generally the truck runs good, went 7.11 1/8th at low boost, non intercooled (it is now). 11.6 in 1/4 on a very hot day. Truck weighs 4,000 lbs.

The problem is at idle you can see it is slightly blowing blue smoke, spark plugs show signs of a lot of blowby. (I have dual breather tanks, 1 for each valve cover).

The motor since rebuilt has always had oily plugs so I suspect the rings are just not cutting it.


So my debate with myself is, in a perfect world I would build a Dart block, forged rods/crank, etc. And not worry about things and be safe to 1000+ hp.
The downside is the bill for just a new block/lower end would be $5k or so.

My other option is to just pull what I have, hone/rering it and enjoy it. Do I go ahead and put better rods/caps in also? Now were talking a $1k bill but I could reuse the rods on another motor later. Still $4k cheaper.

Or do I do option C (you guys fill in the blank).

Just want some opinions as I am sure everybody else has to balance budget and horsepower output.

Wont do anything until this winter unless it just blows up.

 

[Luke]

Re: What do I do? Build a new motor?

rings and a hone, that truck has had too much downtime as is, pull it, ring it, hone it, install it and drive it, your enjoying it too much to down it

 

[dgoodhue]

Re: What do I do? Build a new motor?

So my debate with myself is, in a perfect world I would build a Dart block, forged rods/crank, etc. And not worry about things and be safe to 1000+ hp.
The downside is the bill for just a new block/lower end would be $5k or so.

Run what you have until it blows up, build up the motor you really want.

 

[turbodig]

Re: What do I do? Build a new motor?

Ok here is the background and the truck.

http://videos.streetfire.net/video/Life-of-92-GMC-Typhoon_165068.htm

Truck is running good, working through bugs as I get time/motivation.

The base engine is left over from a 67 camaro I owned at one time. It was never built for boost or even this much power, but I had it laying around and had to use it for something besides a dust magnet.

So now that it is running I am honestly happy (for now, I am sure that will change) with the amount of power it is making, how it drives and just generally the truck is fun to drive and with the AWD would probably stomp most cars on the street. It was never built as a race car anyways.

Motor currently is
350 bored .040
Manley forged pistons
stock rods (beamed, polished, etc.)
stock crank
total seal rings
041 casting heads with 2.02/1.6 SS valves
full roller rockers
hyd. camshaft
~9.7:1 CR
Twin GT35 turbos running 7psi (wouldnt' mind moving up to 10 at some point).
ARP head bolts, main studs (2 bolt stock caps)

Generally the truck runs good, went 7.11 1/8th at low boost, non intercooled (it is now). 11.6 in 1/4 on a very hot day. Truck weighs 4,000 lbs.

The problem is at idle you can see it is slightly blowing blue smoke, spark plugs show signs of a lot of blowby. (I have dual breather tanks, 1 for each valve cover).

The motor since rebuilt has always had oily plugs so I suspect the rings are just not cutting it.


So my debate with myself is, in a perfect world I would build a Dart block, forged rods/crank, etc. And not worry about things and be safe to 1000+ hp.
The downside is the bill for just a new block/lower end would be $5k or so.

My other option is to just pull what I have, hone/rering it and enjoy it. Do I go ahead and put better rods/caps in also? Now were talking a $1k bill but I could reuse the rods on another motor later. Still $4k cheaper.

Or do I do option C (you guys fill in the blank).

Just want some opinions as I am sure everybody else has to balance budget and horsepower output.

Wont do anything until this winter unless it just blows up.

Hone and re-ring... no question. What you have will make/hold 600 HP easy enough.

Find yourself another 350 block, and do caps and a 383 stroker kit, over a period of time.
Top it off with some AFR Eliminators. Dart block is overkill, unless you're planning 1000+
HP, and at that point you'll be re-doing the rest of the truck.

Scrounge ebay/yards/swap meets for stuff. The crappy economy will be in your favor for finding good parts deals. But don't keep a perfectly good running truck down for years to do it. When the new long block is ready, you can just drop it in.

 

[JSM]

Re: What do I do? Build a new motor?

Here is the debate about using a 350 block. Jeremy discovered many years ago at about the 6-700hp range stock blocks will split in half. Granted he was spinning a few more rpms than I plan to but still we both feel at 600hp that is near the edge.

If I get a block (won't be hard, lets say free). In order to machine it for 4 bolts, bore/hone, deck, cam bearings..... Probably be a $1k bill just for the block prep.

A new dart is $2400 and from what I have read aside from final hone and maybe decking it they come ready to go. So for a bit more $ I have something I know can handle 1k hp. Wether I go there or not.

Overbuilt, well duh. But if this build made any sense to begin with I would not have started with an SUV that weighs 4k lbs either.

Again not going to do anything right now, just keep changing plugs as they build up the oil. Otherwise truck still runs good. Just a bit of a concern in back of my mind how long will it last.

 

[4C FED]

Re: What do I do? Build a new motor?

Run what you have until it blows up, build up the motor you really want.

x2.
It runs...so enjoy it in the mean time.
Work on another motor as time & money permits.

 

[canadian]

Re: What do I do? Build a new motor?

marvel mystery oil. be done with it. after having my truck sit for the better part of probably 6 years i would say drive the pi$$ out of it while you can.

 

[Foot Performance]

Re: What do I do? Build a new motor?

x2.
It runs...so enjoy it in the mean time.
Work on another motor as time & money permits.

x3 I would run and start building its replacement as you get the cash :tup:

 

[Syclone0565]

Re: What do I do? Build a new motor?

build up the dart block on the side and have fun with what you finally have running. When the other motor is ready to go in give the JSM crew a call and we can swap it out on a Saturday. That way there is no down time and you can have fun now and later

 

[MikeRenz]

Re: What do I do? Build a new motor?

Easy Solution: Have Willy donate his motor to you once the new one is installed. FREE for the win!

 

[JSM]

Re: What do I do? Build a new motor?

ls1 vs my old sbc. New headers, downpipes, motor mounts, etc etc.

Yea that doesn't sound like a quick solution.

 

[MikeRenz]

Re: What do I do? Build a new motor?

take all the other stuff that you need too :lol: You made it...its yours!


buy a short bus like mine...it came w/ a 4bolt 350 (pretty sure) and a 4l80e. That'd save you some machine work at least and give you a place to store lots of shit.

 

[SY2455]

Re: What do I do? Build a new motor?

If you are thinking about a new motor, take the big jump up to the new LSX block. It comes rated up to 1500+ HP with some putting out 2500 hp with a price tag of $2,120.56 for the tall block good up to 500+ cid.

 

[TYTILIDIE]

Re: What do I do? Build a new motor?

I wouldnt blow it up because then you are risking your turbos. Id probably drive it and get a whole other motor and build it up. Build it like a SYTY motor, rods, pistons, youre done. And maybe some good head work.

 

[SY-1193]

Re: What do I do? Build a new motor?

+1 for LSX.

 

[JSM]

Re: What do I do? Build a new motor?

LSanything requires new headers, dp, intake piping not going to get into complete fab again.

 

[Syclone0565]

Re: What do I do? Build a new motor?

LSanything requires new headers, dp, intake piping not going to get into complete fab again.

yeah don't do that, the truck won't move again till 2015

 

[Xplicit Racing Design]

Re: What do I do? Build a new motor?

re ring it and put it back in, then build the motor of choice, i have 2 customers with stock blocks over 1k horse on nitrous, the only thing saving them is they are half filled with block cement, which i will add did not affect street cooling at all to my surprise, if you dont absolutely grenade it just sell it to offset the new motor cost

 

[turboj91]

Re: What do I do? Build a new motor?

Testing my memory here. 67 350's may have had a small journal crank (might have been the 327 that had both). I would check on that first. If I read correctly, the engine was sitting for quite some time. Was the .040 procedure done long ago or just recently? If it was long ago, the ring seal may have been disturbed from sitting and then moving and that is the cause of the blow by. If that is the case, as long as a good hone does not increase piston to wall by too much, I would hone it and file fit oversized rings and get it back on the road and enjoy it for as long as it lasts while you build another engine.

If the .040 was recent I would suspect some type of problem that will quickly worsen, I would get a 4 bolt block and bore it .040 and hone it to proper piston to wall and again file fit oversized rings (would require your 8 pistons to be out and measured for the hone). Should keep down time to a minimum it they bore it first.

If you search for 4 bolt blocks, see if you can find one of the high nickle blocks made in
Canada. They were a bit stronger.

How high do you spin this combination (if I remember the camshaft was not that radical). If you are in the 5500 to 6K range, I would not be too worried about a 4 bolt block (yet).

 

[JSM]

Re: What do I do? Build a new motor?

Max rpm right now is 5800 ish. Depends what shift. Fuel cutoff is low 6k range but never sees that.

I really don't think these rings have ever "sealed" properly since it was rebuilt early 1998. I put about 10k miles on it when it was in a 67 camaro, then another few thousand while I had it in a 68 GMC truck I had. Before putting it in the ty, it was fully disassembled (minus removing the rings for fear of breaking them). I didn't hone the block but did replace bearings and look things over. Heads got rebuilt.

I will probably pull it apart this winter, new rings and inspect things again. If rods show signs of damage throw rods at it otherwise just put it back. I am really down to maximizing what this block can due, or build a Dart block up. I can't see myself investing a lot of money in a stock gm block (unless a bowtie fell in my lap).