Compression Ratio, Too High...Too Low ??? Options

[2-OH!]

Ok folks,

We just finished rebuilding the motor...94mm pistons and cylinders to match...71mm stroke...but old 1.7 case...CC'd the heads and come up with 44 cc's per cylinder...

Do the calculations and we come out with 1971 cc's...Great !!!

But, The problem is the compression ratio is now 10.64 to 1...

The question of the day:
Should I take the cylinders and heads back off and shim them to get a little relief...Probably not going to get much...Might knock it down to 10 or 9.75 (if I'm lucky)...

DO NOT want this thing to clatter and diesel on me when I get it back together...

OK, let me have it...What are your thoughts ???

2-OH!

[Twystd1]

A butt ugly person from NARP has volunteered a complete 1.8 engine to 2-OH so we can yank the 1.8 heads off of it and get then reworked for his engine. His existing heads are boat anchors. Hopefully he can then sell the 1.8 long block (minus heads) to get the money to have the 1.8 heads gone through.

I can do the heads as well as Leamans machinist. Done right and done cheap for our friend.

This will allow us to get a proper deck height and get the job done right first time.

Now there is a secondary problem. 2-OH has a bone stock 1.7 injection system that is on his engine. The system has been gone through and works perfectly.
AND he is running a 2.0 crank and P&Cs.
With these new to him 1.8 heads and heat exchangers.

I don't know much about stock injection. But I am sniffing a 2.0 with a mild FI cam might run lean with those smaller runners and 1.7 injectors.

Who knows about this? As I don't want to help build something that won't work.

Lastly. Those small chambered heads that this thread started with were 1.7 castings that had been surfaced a bunch.
Thats based on what Leamon told me at GAF. He saw them before assembly. He and Ahdoman said the surfacing was cut way into the last cooling fin. Hence the CC issue. Especially on a 1.7 head.
The heads are still on the engine. We won't be using those in this build.
Accordong to 2-OH the valves are now barely touching the pistons.

Jake... If I had my way. We could send you the whole assembly. But that probably isn't gunna happen. We are trying to get this engine finished for basicly free. And it's not that hard to do either.

Thats why we are all stepping up to help.
2-OH has spent so much time on his car. And it is drop dead nice by all accounts. countless hours have been spent on this car.

He has had this engine built twice and had issues both times.
He doesn't have the funds to buy 2.0 heads and go through them. The money simply isn't there.

Me think it's time for the fellas to step up and help.
Leamon is a great guy who steps up all the time for people.
I am going to do the same. Slits is volunteering a complete engine so we can get a set of 1.8 heads off of it.
And sell the rest for money to help pay for the head work.

I am still worried about that injection question. I don't want to do squat until that question is answered.
Hopefully 2-OH will contact Bleysing and get his thoughts on the injection.

Cheers,

Clayton