Hartge head info needed

[1986series6]

Can anyone tell me the specs of Hartge heads for the m30 engine.

Chance for me to buy a head that was purchased in '92 for an 86 635Csi.

12,000 miles on head. In those days was it just a head swap, or

were there other mods that were done along with the head.

Could it be a B35 style head that would bolt onto the stock B34

block and lower compression? Would the bigger valves and hotter cam

compensate for the lower compression?

Thanks for any and all input. Going to post on My E28 and Big 6 also.

[jbd5015]

I think youll find out what you need from MyE28, alot more hartge 5's out there! I knew a guy that had an H7S (E23) but is an E28 guy as well so I bet he'll chime in!

Most of that hartge set up was cam and exhaust. Bigger valves and a hot cam arent going to do too much without some headers and a chip to help with ignition timing.

Im running into the same issue! I've got a B32 head with a Schneider modified cam (282 degree) and dual valve spring setup. Decided it would be silly to put all the work into a built head AND upgrading the motronic system while ignoring the bottom end.

Ive got a 3.5L block and the upgraded head at the machine shop getting new pistons to get compression up around 10.5-11:1

When i blow up the 3.2 head, ive got the spare 3.5L head ill start buildin up to put on later!

[Bert Poliakoff]

I will start out by saying at the right price I would buy that head even if it means putting it on the shelf.

With that said I would like to offer up the following;You guys forget the head has to be matched to the pistons. I have to believe a head bought in 92 has to be a B35 head Ergo a B35 head with B32 or b34 stock pistons will give less, than more HP gain. unless you have a B35 engine, due to compression loss because of the larger combustion chambers. Appropriate to the piston crowns HP will be gained but not huge. One has to remember basically an engine is an air pump, the more air in and the more efficiently out the more power. It's that simple. In building an engine, it's like a puzzle. Each piece depends on the next to properly make the whole. In building my engine, I wanted something tractable but with a bit more reliable Hp. I started with an M90. I went to true 10:1 pistons custom made by JE, all ports matched , ported and polished, a 284 cam reground by Schneider cams in San Diego , stock valves with a 3 angle cut, and the throttle body is 2mm over sized. Of course everything is balanced as well.I will be using the euro ECU which I am led to believe should adequately run the car with these mods. At the same time i am running a full 2 " exhaust system and am running open loop with out cats. We will fire the motor for the first time in the next several weeks and I will finally see what I have ended up with. The engine builder has felt a conservative 250 RWHP

[Shipper]

Bert,

Nice setup. Forget hp however as it is how she drives not what engine hp you are running (within reason of course). Whether or not you end up with 250 rwhp or 220 rwhp if she runs like a rocket that is what you are after. 250rwhp is around 304hp at the flywheel and the M88/3 ran 286hp so i'd chime in and say that 250rwhp may be achievable but at the high end of expectations, not the conservative end. Start a topic on it and post some photos.

My endurance race S38B38 is half way through dyno now. I'll swap dyno sheets.

[1986series6]

Well, I guess you all convinced me.
I'll put in the pistons. do I get the stock B35 pistons, or do you guys recommend
something more exciting?

[Shipper]

Forged high compression pistons for sure. Although you need to do a lot more to get more hp the forged pistons will be super light and can be balanced. Go for something like 10.5:1. Valve clearances should be fine even with a cam upgrade in the head. If you are rebuilding the engine, go an overbore, hone the bores, balance the pistons and conrods. Deck the head to ensure it is flat as some come bent like bananas.

Would love some pictures.

[Bert Poliakoff]

It ain't that simple. The pistons have to be fitted to the block and the head together. The machine shop building the engine should be doing this. You don't just go out and buy a set of pistons and slap them in. It all has to fit together. the crown of the pistons have to fit the combustion chambers the small end bushings have to be located in relationship tp to piston crowns etc etc etc. Everything has to be matched. After years of use the block has to be decked to make sure all is square and not warped and on and on. My pistons were custom made to the engine builders specs by JE Pistons in Orange County CA Cost was about $800 with rings and wrist pins for forged pistons and these guys are as good as it gets. They were also sent back 2x as the engine builder was not satisfied with the fit. Shipper can back me up on this and tell you what he went through on his engine build with similar problems. you are entering the big time with a custom engine build and there is only one way to do it..the right way or your pissing in the wind. As I said before, it is like a puzzle and each piece has to fit the next correctly or the whole thing doesn't work.

[Shipper]

All true Bert. I may have over simplified things. But, taking into account what Bert says above, now is the time to up spec things while you can.

[digger]

All true Bert. I may have over simplified things. But, taking into account what Bert says above, now is the time to up spec things while you can.

it is actually pretty simple, do a tiny bit of reading on the matter and if youre not familiar with the engine you have then you take a few basic measurements and basic maths when you strip it down. the only one that's a bit complicated in the crown shape is the m20 due to the squish band on some of the heads. any of the 4V stuff or m30/m10 etc is straight forward

[1986series6]

Thanks to you all.

I'm taking the B35 Hartge head and my stock B34 block to an engine builder in Nyack NY.

Yep, I could not believe that one of the best engine builders on the east coast is Charlie Olsen.

I remember buying performance stuff for my 510 Datsun from him in '74.

He's going to check it all out, suggest options and work with me on things that I can do myself

more for the challenge than to save some money. Building an engine is something I always wanted to do.

So it'll be a winter project and I'll update as often as possible.

[e24mpwr]

Again - I want a dang like button here...