upgrading 3.0L --what heads do I need?
 

Am contemplating updating my getting tired '82 3.0L litter engine. If I use the 98mm Max Moritz pistons, do I have to get 3.2L heads or can I use my original 3.0L heads?

98s were made to be a "drop in" replacement on the 3.0. Your heads will be fine.

rdane,

thanks. Next step, will 964 cams and my CIS work well with them for a street car? I am afraid my CIS might not take to these higher compression pistons.

964 or 20/21 cams work great. The Max Moritz 9.8:1 set up was designed as a 3.2 short stroke for the 3.0 CIS cars and single plug with 93 octane gas.

I have a 3.0 that I added the MM 98mm P&Cs and a 74.4 crank for a 3.356liter (commonly known as 3.4) and love it. Only difference is you'll be using the standard crank for a 3.2.

A search for "3.4" and "Max Moritz"will get you a wealth of info, dyno sheets ect.

But having BTDT I would caution you on building with 3.0 if you don't already have cams and SSIs. There are better ways to gain HP for the money involved. If you want to stay with your original 3.0 engine then you are looking at one of the best mods for the SC engines.

rdane,

I have assembled newly ground 964 cams, headers and a sport muffler. My stock '82 SC 3.0L that is still in the car has the bottom end I will use as well as the CIS. An ebay auction is selling the 98 mm p/c and newl reconditioned 3.0 heads. I am debating buying the p/c and heads. I am now wondering if I should bid for them and how much should my maximum bid be? here is a point in such bidding where it is better to fold and that I am trying to decide. If it gets too high one might better spend their money on going with a used bigger displacement engine.

I haven't looked but I would bet those are my buddy's Sherman's parts from his 3.2.

Do a search here under Shuie and then ask Shuie/Sherman about them.

If you have cams and exhaust it is a good upgrade price wise. The price should be better than new as well. His set up was done for 40mm carbs and not CIS and ran a GE40 cam. CIS won't run a GE40.

But the same set up will run 964 cams no problem. The new heads will save you a valve job down the road as well plus they are the early heads ('78/'79) IIRC which add a bit over the later and smaller heads.

rdane,

I have pmed Sherman.... I think his heads are the later ones with the smaller ports... but for what I am after, they will be fine. I just want a little kick up from the stock engine.

"My current heads are 34mm intake SC heads ('80-'83) with all new valves, springs, and retainers. Everything is stock since I never expected the engine to rev past 6700RPM"

Yep 34mm...sorry.

Right - you may want to look for the 78/79 heads when you do this upgrade to take advantage of the larger ports...

-Wayne

If I were to do it over again, I would have had my ports machined out to early SC specs, and put on an early airbox/runners.

Here is why.

Tom

Tom are you still thinking heads and not compression?

Yep, my heads were the later small port variety.

Do you have to pass emissions with a '82 in WA? How wild of a rebuild are you thinking of doing?

Unless I was doing an induction and a cam change I would keep the stock heads. Carbs, EFI, or better yet MFI ;), with a hot cam and I would go ahead and have them ported to 39mm.

The earlier CIS systems should probably also use the 39mm intake ports since the runners will be larger than the '80-'83 CIS runners. IIRC, 20/21 is the max cam you can run with a common plenum CIS or 3.2 Carrera intake.

This stuff gets expensive real fast. Make sure you have a crystal clear plan before you start buying any parts or sending stuff out to the machine shop. I wasn't real worried about the smaller intake port size on my heads until I decided to re-engineer the induction at the last minute.

I CC'd everything, and it measured out to a hair over 9.8:1 (advertised as 10.3:1 with RSR heads).

The AFR is fine (if not a little rich), I can't think of any other reason for the torque to drop off as fast as it does. If anyone else has a plausable explanation, I am all ears.

Tom

Sherman,

I have no emission test on my car.... I live in Maryland and it is considered "historic" and exempt. I am thinking of keeping the CIS anyway and using the 964 cams I aleady have. I also have headers and a sport muffler... the question mark is the p/c.