Post/Pre 89 Engine Q

[dumbo]

Well...
Currently I have all the electronics to go with a pre 89 engine block, 86.5 7M-GE to be exact.(That surcomb to much abuse and FUN:evil2 It only pushes a few ounces of coolant into the overflow after a 1/4mile pass, and lightly bubbles when warm, but the ugly has shown itself. On to the question.
Can I use a post 89 block that will have 7m crank, and the "beefier" block, with pre 89 electronics, plus doesn't the pre 89 ECU rev higher? I'm going to be using everything I have on the GTE block, Maft Pro w/speed density, RC 550's, ETS intercooler 2.5" IC pipes...

Is there a good sheet or list of machineing "needs" for my engine builder?

This is just a couple of questions I currently have, it will get much bigger I guess I've been waiting to destroy my GE to move onto bigger and better and more reliable things...Plans are to have her built or ready to be built for spring.

Lets hear it all guys/gals.

 

[CyFi6]

your harness and ECU year needs to match (yellow or gray) whatever the year of the body is. beside that, you can mix and match any mechanical engine parts, as long as you use the sensors from the same year as the harness. But you cannot use 7mge wiring for a 7mgte either.

 

[gaboonviper85]

Machining is a crap shoot...there is no "one way is best"! Your machining needs will vary depending on cylinder wear, valve train wear, internal damage (rod knock), horsepower goals, internals chosen for rebuild, etc

for us too assist you in coming up with a list of machine work, we'll need too know your goals and the parts you plan on going with.

For example: probe pistons generally come with NPR chrome piston rings....these rings are TOUGH! You're machinist will need too put an agressive almost ruff feeling hone finish in the cylinders too assist in the piston ring bedding process (generally requireing you too beat the shot of the new motor too seat the rings good)! Doward knows the specifics on the hone finish...

Puter rods (I believe) require the oil pump driveshaft too be turned down for clearancing from the rods as they will collide causing catastrophic failure...

For high horsepower you'll want too open up your bearing clearance too the max per tsrm...this let's the crank have room to breath as out blocks twist and bend and do all sorts of funny stuff when you crank up the boost...(IJ took the liberty of figuring this out with his time,money, and dedication too perfection!)

you may or may not need too replace valve guides...this can get expensive! Pray you don't have too odds are you won't...but if you do then you'll def pay for it!

The possibility of us knowing what you need done is impossible....some of us may be able too give you a good starting point but it won't be perfect as we don't have the motor in our hands and majority here wouldn't know a Bridgeport from their asshole...although there are some machinist on board (myself included);-)

 

[gaboonviper85]

Also as far as machining "needs"...that's a matter of personal opinion keep in mind!

What machining comes down too is...how much
money you are willing too spend...

I'll put my experiences in perspective for you...

Engine block hot tanked, bored/honed .020" over, decked, hot tanked again, crank polished....machinist fucked my block deck up too the point I didn't feel safe using it! -$576 down the tube...machined by Ecam in glenside PA

engine head...straightened, decked, valve job, pressure test....after machine work was done they found a crack in the head near a valve seat...$700 didn't pay them as they didn't inspect well enough before machine work and didn't call me till after it was done...-$120 for cost of head down the tube...machined by RT tuning in lansdale PA

recent engine head...same as above but cost $527 and head looks like pure sex! Machined by andalusia speed shop (sp) in Bensalem PA

wish I worked as an engine builder instead of industrial machining:-(

 

[dumbo]

Technically I don't have a long block yet, undecided if I will use my head, want to see if it is annealed, and if theres enough meet to deck it again.

For the engine block, I read somewhere that somthing(timing cover??) needs to be removed and machined for a proper MHG seal? I need, maybe a better word for it is a list of tips for my engine builder.

I want the long block to be good for 5-600hp. But I also want it to be be very street able with just my ct-26 57trim and rc 550's, 3inch turbo back, and stock intake manifold. So 350-400hp until I get bored of my turbo, and then upgrade without having to worry about the engine.

I'm unsure of the rod/piston combo right now, I was hoping to find thread about pro's and con's of some setups but no luck yet. I'll be having the head totally rebuilt, and probably ferrea 1mm over valves/springs ect.

Is stuff like a crank scaper neccasary?

 

[toy fanatic78]

Timing cover has to be bolted to the block when head is decked.Also need the timing belt tensioner torqued down when boring the #1 cyl.

 

[speedgilligan]

you definitely need to use a torque plate as well if you are going for a bored block!

 

[gaboonviper85]

you definitely need to use a torque plate as well if you are going for a bored block!

This is bullshit! No you do not "need" one...yes they are nice too have! Toyota didn't use one so it's obvious they aren't that critical...now when you build a race engine then yes it's a damn good idea!

The rear timing cover is too be bolted too the block when the "block" is decked not when the "head" is decked!

Keep in mind that je, Titan, probe, etc pistons all require a certain piston too cylinder wall clearance....you'll want too consult the piston mfg for what the clearance should be for your hp goals! Same goes for ring gap...IJ can go more indepth about this if you ask him.

+1 for the timing belt tensioner torques down while boring the block!

The block and head will require a very smooth finish of ruffly 50-30ra or better depending on metal gasket mfg'r....cometic is 50, hks is 30...but smoother the better!

 

[dumbo]

Good stuff, keep it coming guys. Still looking for what rod/piston combo I should use. As for the torque plate, I think I'll use the head off my GE as a toque plate. I remeber a while back someone trying to find one and couldn't. But my builder might have one. I'm going to auto x this thing as well as drag racing. Nitrous may be considered down the road for kicks. It wont be baby for any of its life, so it's gonna need to be perfect. I'm hoping IJ puts his 2 cents in.

 

[gaboonviper85]

Too turn a head into torque plate will not only ruin it but also cost more money too machine it than too buy a plate from sip! IJ is the one who used a head as a torqueplate but IJ also has his own milling machine!

Piston and rod combo is your choice as they are all decent...can't go wrong with weisco or je pistons that's for sure!

Also I'd rather use a head from a ge than a turbo as the ge head hasn't seen the type of temps a turbo car has...unless the motor was overheated. Your call but you need too give a budget for parts and a budget for machine cost....

 

[dumbo]

Yah I was hoping he has a torque plate. Internals are slowly going towards Eagle Rods, Je pistons, Ferrea valvetrain. My head was overheated but whats a good call to tell if its "anealed"? IJ, JDUB, lets hear IT@@!!

 

[gaboonviper85]

Yah I was hoping he has a torque plate. Internals are slowly going towards Eagle Rods, Je pistons, Ferrea valvetrain. My head was overheated but whats a good call to tell if its "anealed"? IJ, JDUB, lets hear IT@@!!

I'm not Ij,jdub or whoever....but too know if it anealed you need too have the head Rockwell tested! Another major indication is if the exhaust studs stripped out when you removed the manifold...

Most automotive machine shops don't have a hardness testor....you'll probably have too find a metal heat treating company in your area too test it...takes about 5 min to perform! Look in your phone book for heat treating, machine shop, metal supply...etc

But I'm not IJ so my answer probably isn't good enough...

 

[dumbo]

No no I appreciate all the advice gaboon, I just want lots of different opinions. Keep them coming. It's just gonna be a few pennies, so I wanna get it right the first try.