your engine building opinion please

Hi everyone. I turbo'd my saturn dohc engine. Everything worked great @ 10
psi, turned it up higher and with too much heat the engine block warped and
is shot. Lost all compression in cylinder #1 and some in #2. So i've devised
a plan, what are your thoughts. To buy a cheap SOHC engine for the block and
rotating assembly (because sohc pistons yeild a 8.5:1 comppression where the
dohc has 9.5:1). Rebuild the engine with all new bearings, rings and seals.
And use my DOHC heads (overhauled), intake and fuel system. The heads have
the flat faced valves so comp. would be like 8.7:1. Can anyone see any
problems with this. I know the crank would have to be a 91-92 because of the
crank sensor but it i got a newer engine i would just need the pcm, right?

 

No idea what year engines you are trying to marry up but "Lane" is
probably the most knowlagable person in this group for such things.

8.5/7 would be much better for boosting than 9.5 but you should be using
Forged pistons, not Hypereutectic pistons for boosted engines. So you
might as well buy yourself some forged pistons that will bring your
compression down. Or you could try shoehorning a supercharged 3800 and
tranny in there.

 

No idea what year engines you are trying to marry up but "Lane" is

I would pony up the cash and throw a 3800 s/c in there (thought about it
actually) but for the price i would rather throw a sbc in a fiero or somthin
of the sort. Anyway since i posted i now know any 1.9l sohc or dohc will work.
a 91-92 needs a 91-92 pcm. a 93 -96 needs a 93 - 96 pcm. Newer than that it
is obd2 and gets more complicated. What i really need is forged H beam rods,
that is the first thing that breaks and limits the saturn bottom end at 275hp.
And also with the forged you would have to get the motor balanced and theres
another 250 bucks. I have a lead right now on a 98 sohc engine( the block is
actually stronger than all other years). I will swap in my 92 rotation
assembly with new bearings and dohc heads. Then i can use my existing fuel
system and pcm.If anybody disagrees with me let me know seriously. I know
enough about these saturns to be dangerous. But a 400 dollar low compression
build sounds pretty nice rather than going forged.

 

So does anyone know how much it should cost to get a block and head milled
flat and checked for any problems? If my car ran with good oil pressure
would you guys replace the pump while the engine is apart? is it o.k. to
compression test an engine on a stand ( like with starter hooked up).
Would you hone your own block or pay the shop? Any and all advise is good
Thanks guys

 

You should find everything here:

http://www.turbosaturns.net/

 

I've already usedthat site to compile all my turbo info. There is nothing
about my questions I have asked. has anyone in this forum ever taken apart
their motor, I'm looking for assurance since i will be posting all sorts of
useful threads on building powerhouse saturn motors, N/A or forced when all
done with this.

 

Turbosaturns.net's forums used to be the best place to find any and all
turbo-related information and experience, but they went down and disappeared
about 6 months ago. Prior to that point, I had been reading them for
several years before I started my turbo build so I can lend a few thoughts.

Several TSN posters have used the stock block for very high boost levels and
I have never heard of anyone warping a Saturn block. Are you sure that's
what occurred? If so, is that a heat issue? Going with an oil cooler and a
upgraded radiator in the future may be good insurance.

Yes, this is exactly the route that I took. You can read about what I did
in my website's projects section if you are interested (link is in my
signature below). BUT, going with 10psi+ with stock pistons and rods is
asking for it.

You will absolutely positively have to upgrade your fuel system. A stock
PCM / injector / fpr combo won't give you the fuel you need under boost. If
you ran that with your prior setup, I'd say running lean may be what
grenaded your motor. You ever dyno it and monitor fuel/air mixture while
under boost? That would tell you for sure.

If your motor is apart, it's best to put the proper crankshaft in it for the
year group your car falls into. Info on engine/PCM swaps to different years
can be found in the Ultimate Swap Guide:
http://www.saturnspot.com/forum/viewtopic.php?t=19927

Yes, this is good advice.

Now that is an enormous amount of work, but it would yield great results. A
guy who visits my local dragstrip did this so I know it is possible.

"Carjunky via CarKB.com"

I always laugh when people use the words "throw" or "drop" when talking
about a motor swap of this nature. Those who do often have never done one,
because it is a LOT of time and expense. I went through one with a prior
car and will never use those words. Ever.

'96 was the first year of OBD2 and it doesn't fit in that category. So it
should be 91-92, and 93-95.

I wouldn't say that you have to. I had no plans to do so with my build and
very few turbo'd Saturn owners have. It's a lot of cash for very little
benefit.

I believe it is '98 and up, and not restricted to just 1998.

Oooh, this makes me cringe.

From the boost level that you've stated, plus the fact that you're building
the second motor after killing the first one, I'd strongly consider upping
the reliability by going with forged internals and upgrading the fuel
system - or you may find the third engine build coming sooner than it
should.


"Carjunky via CarKB.com"

My local shop does quick measurements for me for no charge - should not cost
much from most shops.

If there is a chance that worn metal has ever gone through the pump, or your
pump/timing cover has a lot of miles, then YES - I'd replace it if it were
me.

I honed mine myself with a $25 tool and instructions I found on Hastings
website (link is on my site).

Good luck,
Lane [ lane (at) evilplastic.com ]

 

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There is a big difference between
A: proper very expensive cylinder honing machine using lubricated and cooled
precision stones to size and condition a cylinder bore. This machine is
often used to increase the bore size to remove tapered cylinder wear and
allow the use of oversize pistons. This is often the machine used to 'bore
out' a cylinder rather than the older technique using boring bar followed by
honing.
B: springy, inexpensive attachment for a power drill that is more properly
called a 'de-glazer'; which is a non-precision tool that is normally used to
scratch a cross hatch on the cylinder wall to encourage quick ring seating.
These tools come in a variety of styles some using mounted stones and others
with abrasive balls on multiple springs, they do a good job when re-ringing
but extensive cleanup should follow any use, and they do increase piston
clearance.

A proper engine build should involve obtaining proper pistons then precision
honing the cylinders to properly fit the individual pistons. This fit is
often tested by measuring the force required to withdraw a feeler gauge.
Anything short of this is usually a simple re-ring.

Good luck.