engine rebuild question

[gsxr141]

bear with me, as this will be my first rebuild....

i have a freshly rebuilt shortblock ready to go into the car. i'll be using all the parts from my running engine on it. the running motor was rebuilt not long ago, and has arp headbolts, and possibly an hks mhg. the question is..... can i reuse the head and gasket as-is? i shouldn't have to machine the head again, right? there's no leaks, so i'm assuming the head was machined already, and the job wws done right.
any help would be great...... thanks...

 

[nofx230]

MHG needs a resurfaced block and head to the right spec, if you pulled the head off the motor for the rebuild and have not resurfaced it i would deff get it done,or at least check for warpage with a quality straight edge, the head will usually warp before the block even on a car that didn't have a blown HG. its just insurance for your car man, if you can't buy a new MHG and have the head resurfaced to do it right now, id wait until you got the flow to do it right. just my two cents

 

[gsxr141]

thanks.. the head is still on the running car now. i was wondering if i could just take it off and install it right on the new motor. so basically, every time you take the head off you have to have it machined again? even on a recently rebuilt motor?

 

[hvyman]

Yes. You should have the head machined everytime you take it off.

Your better off getting a new hg instead if trying to reuse the old one.
In order to reuse you need to take the hg layers apart clean all the viton off so there silver. Coat each side of all the layers with copper hg spray and reasseble in the same order it was taken apart in.

 

[nofx230]

yeah I'm not even a fan of reusing a HG. in a sense its just cheap insurance to get a new HG, plus once you have the head resurfaced you may want a thicker HG due to the amount of material that has been removed off you head, unless you plan on running a higher compression set up

 

[IJ.]

I reused all of my MHG's 4x before retiring them to the bin..

Careful inspection then cleaning properly and applying VHT Copper coat = no issues ever.

 

[gsxr141]

thanks guys. i was under the impression that the metal ones were reusable. i'm going to probably just get a new one.

 

[nofx230]

I reused all of my MHG's 4x before retiring them to the bin..

Careful inspection then cleaning properly and applying VHT Copper coat = no issues ever.

4x you say now thats dedication, one day when i decide to go MHG ill remember that!

 

[IJ.]

4x you say now thats dedication, one day when i decide to go MHG ill remember that!

When you pay $400 for a MHG it's hard to bin it each rebuild, no matter how big your parts budget is.

Could probably have been reused more but I figured 4x was enough, ditto on the ARP fastners.

 

[nofx230]

When you pay $400 for a MHG it's hard to bin it each rebuild, no matter how big your parts budget is.

Could probably have been reused more but I figured 4x was enough, ditto on the ARP fastners.

just outta curiosity IJ, but over what period of time did you reuse the same head gasket 4x and why? did you pull the head off to recheck work or...

 

[IJ.]

From memory I went through 3>4 MHG's over the 13 year lifespan of my 7M, lots of development work and upgrades.

 

[nofx230]

i gotcha, didn't realize this was over a 13 year span, was thinking for some strange reason a span of like 2 years. lmao sorry man

 

[IJ.]

i gotcha, didn't realize this was over a 13 year span, was thinking for some strange reason a span of like 2 years. lmao sorry man

This was the car's final spec before I swapped in a T04Z LS Chev, I sort of have a bit of a clue

Brand new GTE block

7M Niterided Lightened Crank

+40 thou Triple coated JE Forged Pistons

Pauter Rods

ARP Main studs

New GTE pump

GrpA Magnesium Pan
Canton Remote Filter adaptor
Canton Remote Filter mount

HKS Stopper 2 mm MHG

NDC Rod Bearings
NDC Main Bearings

B&M Oil cooler
B&M T Stat
Moroso 3Qt ACCUSUMP

ATI Super Damper
Aluminium engine pullies

Wade Cams .351"/9mm lift
280 degrees duration 226 @ 50thou


+1mm Ferrea Valves
Ferrea Valve Springs
Ferrea Titanium Valve Spring Retainers
Ferrea Valve Seat Locators
Shimless buckets
Brand new ported head

2 x Aeromotive Tsunami pumps
Aeromotive AFPR
2 x Bosch MS filters
2 x -6 fuel lines
1000cc RC p&h Injectors
115 litre "IJ" tank
"IJ" Multipoint methanol injection

AEM cam gears
Gates Timing Belt
ARP head studs

T04z 800hp roller turbo
Tial v44 WG
3.0" Aluminium Hardpipes
Turbosmart 32mm Bov's x 2
600x300x100 air to air IC

PWR Radiator
DC Electric water pump

321 Stainless Ceramic coated Header

New design "IJ" FFI intake manifold

"IJ" DBW 68mm TB

3.5" Mandrel bend Dump pipe
3.5" Metal Cat
2 x 2.5" Mandrel bend Stainless pipes
2 x 2.5" Stainless Mufflers
1 x "IJ" Muffler

Bosch coils x6
2x M&W 3 channel ignitors

MoTeC ECU
MoTeC DBW4
MoTeC 2 axis G sensor
MoTeC EGT
MoTeC wb02

NGK PowerDex wb02

55watt 5000k HID lights

Built a340e
PCS Trans controller
2800 rpm Hi-stall TC
B&M Fan cooler
DCraig cooler
Full electronic valve body

Strange Nodular Iron 9" case
3.5:1 Motive Gears
3.5 Trutrac 9" Diff
Custom "IJ" 9" housing

Custom Axles
GroupA V8 CV joints
Custom Stub axles
Diff cooler and pump

Full Strange Engineering Driveshaft

Mk4 TT DBA Rotors F&R
AP Racing 4 piston callipers
SS Goodridge lines

Koni Yellow Coilovers
Eibach Springs

Whiteline Swaybars
Full Poly Urethane bushes
SS Lower Control arms

18" x 9" HR109 rims f&r
265/35/18 452 Falken tires front
285/35/18 452 Falken tires rear