930 Rebuild (street only)
 

After much thought, it is time for some upgrades for my 79 930. I am a regular reader of this forum, but this is my first post. I am planning to upgrade the head studs, tensioners, exhaust, cams, clutch/pressure plate, and turbo. The case will be split for a complete rebuild etal. I value the advice of fellow Pelicans that have gone before me. The car is a low mileage stock 79 930 that I drive almost everyday. No track or racing, just enjoyable street driving in the 2500-5000 rpm range. I am seeking some performance gain, but mostly peace of mind and day-to-day reliability. I would like to keep the car as "original" as possible. I appreciate your suggestions.

Hi, congats on finding this place-you've just saved yourself a fortune and spent a fortune in one go! So your engine is a low miler thats not thrashed and in good condition? If there are no serious issues (i.e. broken head studs/low oil press/lots of smoke) and you get some good leakdown figs then I would advise some simple bolt ons to start with- straight forward stuff that will ease you into the vast ocean that is modifying 930 engines. you can expect some real good power gains and a lower spool up from things such as headers (B&B/GHL) K27 high flow turbo, bigger intercooler etc. all of which you could call 'weekend mods' and don't reqiure any serious modifications to install. If you want more then you could start thinking about pulling the engine out and tearing it down but if i were in your shoes I would go with bolt ons and enjoy it sooner! hope this helps

Adomakin, thanks. I have selected a B & B header/muffler exhaust system. I am most concerned about the cams and turbo upgrades? I had not planned to change the intercooler as I will be running 1.0 bar, but if an upgraded intercooler will improve engine life and reliability, I would consider it. Any advice is much appreciated?

The intercooler is a must do a search, there are toons of options out there at varied prices.

and the stock intercooler is a piece of crap. At air temps above 80F it becomes heat soaked and actually adds heat to the turbo discharge.

intercooler is a relatively cheap way to add some power and reliability. on top of that you can put a water fogger, think windshield wiper bottle and nozzles spraying on the intercoolar. say what you will but it helps when temps start to get out of hand, not a long term cure but for short stints it is great, my cousin runs one on his supra, one of the fastest on the west coast to great effect.

forget the water fogger, it is complicated and really a bandaid fix, what you need is a properly sized intercooler for you application, there are a litany of options out there depending on what you want to spend and the quality you expect.

Hmmm... Lots of rally teams would disagree with you.

In fact, my EFI software has a provision for water-cooling the IC by boost, throttle position or RPM.

What about cams (SC vs. SC 330 vs. 964) and turbo (K27 7200 vs. K27 S) given my desire for more low/mid range power. As I mentioned before, I have chosen a B and B header exhaust, does it make sense to go with a long neck B and B intercooler to match? Any experience with Blownsix intercoolers?

SC cams, bigger intercooler and modern turbo will go far. Porsche crowd defaults to KKK K27 most of times, being conservative and all. But there are better turbochargers nowadays. Garrett GT35BB is very nice piece of equipment and more-or-less state of the art when it comes to reasonably priced road stuff.

The Blownsix intercooler can be had for a good price right now because they are not "out there" yet. A buddy just bought one and should install it soon.

Beep - so if we don't have twin monster turbos hangin' out the back and an intercooler that won't fit within the confines of normal bodywork we are conservative? HA!

the water fogger doesn't work near as well as direct methanol injection. which costs about the same and uses most of the same parts.

Hehe...no, but you must confess that confess that majority of 930 afficionados still buy those K27's for some quite hefty prices, despite being old design.

http://www.pelicanparts.com/support/smileys/drummer.gif

There are many versions of the K27 turbo available - given the new SC cams, B & B headers/exhaust and the desire for much better low/mid range performance - any suggestions on the K27?

The stock K27 is not a high performance piece. Even though you state you will not go over 5000 rpm (first time I've ever heard that...), you should upgrade to something more modern and flexible (will accomodate your future mods). If you are a DIY kinda guy, look at the Garrett's. If you are looking for a bolt-on solution, look to Kevin at www.ultimatemotorwerks.com. Bolt-on however, comes at a price.

DonE, sorry for the confusion. I definitely go over 5000 rpm.... I just want my useful power band to where the bulk of my driving is. That would be from 2500 - 5000 rpm give or take a little. My preference for a turbo upgrade is a DIY bolt-on solution.

Any thoughts on using a stainless steel head gasket on a 79 930 engine?

Yes, you can use the C2T 3.3L turbo head gaskets in your engine for even better sealing at higher boost levels (< 1.4bar). If you plan to run any higher boost levels, then you need to look at Flame Rings (Nerosist).

I run C2T head gaskets in my motor, as recommended by Protomotive :cool:

Pushing 930: I'm chasing the same subject you are...and rather than put the board thru the same questions, I'd like to hear what you've decided and why...but I can't email you privately because you have indicated you don't want to receive email. If you could contact me at fishoncj@aol.com I'd like to discuss what options you are considering, and what you've found so far. Regards, Chuck

Welcome.

Here is one source: www.goingsuperfast.com (I haven't used these guys (yet-don't know if I will) but found the information helpful while researching turbo upgrades).

It sounds like you are talking about a top end rebuild with while you are there performance upgrades. What has your machinst/builder advised?

Do you have compression/leakdown numbers to justify tearing into it? Is it using too much (>1 qt/1000 mi)oil. Is it leaking oil?. Don't forget the oil lines.

Seems like you take it easy, yet are nearing the the slippery slope.

Have fun. Be safe. And good luck!

Regards,