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If the floor doesn't have any holes, consider buying a gallon of EvapoRust, or something similar, and just pouring it onto the bare floor. That way, you don't remove any metal, and create holes.
 

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Discussion Starter #22
If the floor doesn't have any holes, consider buying a gallon of EvapoRust, or something similar, and just pouring it onto the bare floor. That way, you don't remove any metal, and create holes.
I was thinking some paint-over-rust. I've had good luck with that on other cars
 

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It's so easy to chemically remove the rust, that you should do that first. I've tried the painting over it, with a PUR type paint, method and it ends up having to be redone.
 

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Discussion Starter #24
It's so easy to chemically remove the rust, that you should do that first. I've tried the painting over it, with a PUR type paint, method and it ends up having to be redone.
I'm certainly willing to give a rust remover a try but I've had really good success with various rust remover products on my 72 Buick. I did the brake drums with a rattle-can por and the front of the frame with brush-on POR-15. I've had mixed results with the various rust removal products I've tried.
 

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Discussion Starter #26
Since my last post progress has been slow. My main hangup has been on my engine. I wasn't totally sure what I wanted to do when I started the build and i've been figuring it out along the way. I recently acquired a stock rebuilt 287 head from GLHS60 which is super exciting. I disassembled my turbo to see if it was rebuildable. After getting it all apart I decided a turbo rebuild is above my head, especially without any way to balance the rotating assembly. Currently I'm trying to choose a head gasket. I've been impressed with what I read about cometic's headgaskets, but I'm overwhelmed by the options. I'd like to keep compression at 8.5:1 but without knowing the head gasket bore diameter and the cc volume of my g-head I'm not sure how to reach that number. Some searching hasn't helped me find these numbers. does anyone know these?
I've decided I want to do the PT lifter upgrade on my head, find a new cam (my '87 slider is badly worn and unusable), find a turbo, and then it's assembly time! My main concern on assembly is the vacuum system. On disassembly nearly every single vacuum line fell apart. I still have the remains of all of them but I'm unfamiliar with vacuum systems. I've decided to use the stock electronics for now, at least until I get the car running. I've never heard the car run and I'm anxious to drive it for the first time!
I also got the fourth wheel for my set of Italian 5 lug pizza wheels and I'm now searching for a shop that will refinish and widen the wheels. Has anyone ever widened stock wheels for these cars? I'd like to make them 15x6.5" so that I can at least run stock size for the Shelby Z.
Finally, I started doing a little interior work. The cloth doors were all screwed up from heavy water damage so I've decided to redo them in a dark marine vinyl. I'll post pictures once it's all finished.
 

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Hey Isaak:

I don't remember you wanting to raise your compression ratio??

One of the G head's main benefits is it lowers the compression ratio.

Lowering the compression makes the Engine less detonation prone at higher boost.

A stock 2.2 Turbo Engine is rated at 8.1:1 where a 2.5 Turbo is 7.8:1

8.5 is getting high for our Engines and lessens the detonation safety limit considerably.

A few guys have tried 9:1 but I don't know of any who have had success.

I don't have any Cometic experience so no recommendation there.

I always run MP gaskets that compress to about .068" but they were scarce for a while.

I heard Chrysler has a replacement that covers the 005 and 006 but haven't used one.

From memory, G heads are about 56cc and swirl about 50cc, Todd will know for sure!!

Thanks
Randy
 

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Discussion Starter #28 (Edited)
Hey Isaak:

I don't remember you wanting to raise your compression ratio??

One of the G head's main benefits is it lowers the compression ratio.

Lowering the compression makes the Engine less detonation prone at higher boost.

A stock 2.2 Turbo Engine is rated at 8.1:1 where a 2.5 Turbo is 7.8:1

8.5 is getting high for our Engines and lessens the detonation safety limit considerably.

A few guys have tried 9:1 but I don't know of any who have had success.

I don't have any Cometic experience so no recommendation there.

I always run MP gaskets that compress to about .068" but they were scarce for a while.

I heard Chrysler has a replacement that covers the 005 and 006 but haven't used one.

From memory, G heads are about 56cc and swirl about 50cc, Todd will know for sure!!

Thanks
Randy
No, I have no desire to increase compression. What I want to do is keep my compression ratio close to the stock CR (which I read somewhere was 8.5:1). To do that though, because so much on my engine has changed from factory, I wanted to know the cc of the G-head and the bore diameter of the factory head gasket. The cometic gaskets come in a variety of compressed widths and I want to buy the size that will give me the closest to stock CR as possible that way I don't have to use a head shim.
I wasn't able to find this information easily on the forums so I thought I would ask here in case somebody knew.
 

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Good, I was concerned with your 8.5 #

Stock your compression ratio is 8.1:1 with your pistons about .018-.020" below deck.

You will have to check if and how much your block has been decked for starters.

You won't be using a head shim in any case as you will be a bit lower with the G.

To figure the exact compression ratio you'll have to cc everything and calculate.

Many don't bother as we know the combo is a proven one at a little below 8.1:1

I'm sorry I don't have my notes nearby as I haven't done any calculations in years.

As mentioned Chrysler gaskets compress to .068" but others maybe less.

Hopefully Todd will notice your thread a he keeps meticulous notes!!

Thanks
Randy
 

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Hey Isaak:

I don't remember you wanting to raise your compression ratio??

One of the G head's main benefits is it lowers the compression ratio.

Lowering the compression makes the Engine less detonation prone at higher boost.

A stock 2.2 Turbo Engine is rated at 8.1:1 where a 2.5 Turbo is 7.8:1

8.5 is getting high for our Engines and lessens the detonation safety limit considerably.

A few guys have tried 9:1 but I don't know of any who have had success.

I don't have any Cometic experience so no recommendation there.

I always run MP gaskets that compress to about .068" but they were scarce for a while.

I heard Chrysler has a replacement that covers the 005 and 006 but haven't used one.

From memory, G heads are about 56cc and swirl about 50cc, Todd will know for sure!!

Thanks
Randy
remember too that the pistons changed along with the combustion chambers

that larger G head chamber went along with a smaller dish in the piston
the smaller swirl head chamber matched up to larger dish in the piston

the later 2.2 and 2.5 used an even larger dish in the piston again

it's this last item that I feel makes tuning a G head on a 2.5 difficult

and if the 2.5 starts at 7.8 -1 then putting the G head on will only lower it again somewhat
- though I think the tuning issue might be a flame propagation issue due to the chambers and pistons not matching properly

I've run both small dish and medium large dish under a G head with no notable difference.. but never the really large dish
those really large dished pistons look like they could lack much ot the strength the small dish piston might have beyond them .. when considering the piston area above the top rings , and how much the dish is cut to almost the inner diameter of the rings
 

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I never had any problems running a G head on a 2.5 Turbo.

The "slow burning" chamber design, as opposed to the "fast burn" and reduced compression made them more detonation tolerant.

Ideal characteristics on a higher than stock boost turbocharged Engine.

Thanks
Randy
 

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Didn't see this thread till now. Too bad, I would of suggested going with a 2.5 bottom end on that thing. One of the best upgrades to my 87 ShelbyZ I ever did. Much easier to drive. Still just as fast. Loves air flow mods. Out-revved the 2.2 it replaced at the track.
 

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+1 on 2.5 in shelby z t top cars !!

also good are black rear inner quarter window trim - easier to see out of quickly
and the lebaron convertible center console and center support tunnel

perky
sturdy
more user friendly
and no more air liner armrest
 
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