turbo performance Options

[nsyr]

I know there a few people out there with turbo 4's. Does anybody have any performance or reliability figures.

[Mueller]

so far no one has stepped up to the plate and dyno'd thier cars that I know of.....the general "seat-of-the-pants" dynos report ~160hp to 180hp

if not abused too bad, the life should be just somewhat less than stock

[fiid]

"Everyone knows you can't turbo a type IV"

I estimate you can get a 20 - 30 percent gain on output without killing too much. I have been told that the problem is you cannot get serious boost on without the heads falling off (since they are only held on by 4 studs per cylinder and they tend to pull.

There are suprisingly few turbo type 4 engines around - it's not a delighfully easy thing to do - I tried it and gave up. I am doing a subaru motor conversion instead!

l8r,

Fiid.

[Mueller]

I tried it and gave up. I am doing a subaru motor conversion instead!

funny how you consider doing that swap easier than adding a turbo to a Type IV (IMG:style_emoticons/default/smile.gif)

shouldn't you be riding your bike or something getting ready for your bike ride???? (IMG:style_emoticons/default/burnout.gif)

[fiid]

It's not really easier - it just gives a real return. I'll have 280 horse when I'm done. It should blow the doors off of a lot of things.

Fiid.

[Mueller]

you suck !!! hahahaha

I'll be happy if my turbo 1.8 will put out 175hp...it'll still be a fun car to drive (IMG:style_emoticons/default/MDB2.gif)

oh yea...thanks for returning my phone call earlier in the week, LOL

[fiid]

Dude - I totally regret not returning your call -that was the day you were in the city right?

It's typically much easier to pry me from work with IM.....

Fiid.

[Mark Henry]

Mueller, did you see what the monoball guy does on the 911 turbos?
A stainless steel ring with a step that is machined into the head. Third thing down the products list.

http://www.apfvilleneuve.com/racing%20parts.htm

I wonder if it would help with the sealing issues on the T4 heads?
Jake?

[Mueller]

Hey Mark, no, I have not seen those SS rings before. I bought copper rings for my 2.0, but after talking to Jake, I am not going to run them.

Fiid, can you call me today/tonight? I need to pick your brain on your EDIS install....510-484-8700..thanks

[nsyr]

i am considering the suby engine too. it wouldn't be that much more and it would be reliable. So, does anyone have performance figures for a 914 suby? (IMG:style_emoticons/default/biggrin.gif)

[Eric_Shea]

You can't put a Subaru engine in a 914 (IMG:style_emoticons/default/laugh.gif)

[fiid]

I can tell you that a 280Hp Subaru engine in a 914 ought to have a slightly better power to weight ratio than a Ferarri 360 Modena (if my math is right).

The 914 option is slightly cheaper, also.

Fiid.

[Jake Raby]

Hell, if my plots work out the way they are in simulation I'll have a 270ish HP 10:1 N/A street engine to market!

Turbo that witha roller cam and you have over 500 with 8:1 CR!

Just wait!

[fiid]

Jake - do you think the exiswting head attachment mechanism will stand that kind of torture?

Fiid.

[airsix]

Jake - do you think the exiswting head attachment mechanism will stand that kind of torture?

Fiid.

Something to remember about turbos - if done right they can nearly double the AVERAGE cyl. pressure without significantly increasing the MAXIMUM cyl pressure. (That, by the way, is awesome)

-Ben M.

[Jake Raby]

The studs that come with Nickies should hold about anything.. The only way to know is to try. The key is cool running and keeping expansion down... Expansion and elasticity that comes with it kills the sealing capabilities. My heads are very beefy where they need to be, and being made from a chunk of Billet will definately help!

[fiid]

Jake - do you think the exiswting head attachment mechanism will stand that kind of torture?

Fiid.

Something to remember about turbos - if done right they can nearly double the AVERAGE cyl. pressure without significantly increasing the MAXIMUM cyl pressure. (That, by the way, is awesome)

-Ben M.

Well - if that's true - then it shouldn't be too much of a problem....

I spoke to a guy who seems to know what he's on about (he works with one of the regular competitors at the PCA AX) who was of the opinion that "you couldn't keep the heads on it". I never got as afar as why this isn't a problem for type I motors (I actually have never seen a type I motor) - but it seemed plausable. He seemed to think you could run sub 10psi without breaking too much, but when I ran the numbers through some of the turbo calculator programs, it looked like it would be hard to get enough power out of my 1.7 to keep up with 2.0s. I reckoned you could get 130 or so HP out of a 2 litre but it seems like it would be awefully easy to just turn it into a smouldering heap, and since a set of 2l heads can cost $500-$1000 by themselves - seems like a risky proposition.

A decent type IV rebuild just costs a lot of money - probably in the $5 to $8k range - versus the Subaru engine - as a JDM import crate motor costs between $600 and $1400, plus I can grab a new one any time I like.

If I could afford a built T-IV - I'd probably just bite the bullet and go for a 3.0, 3.2 or 3.6 -6 engine.

I might still turbo my 1.7 anyway - just for shitz and giggles.

Would be fun to try and get classed for the local PCA.

[Jake Raby]

Stock Type IV heads do not compliment a Turbo... Not in any respect from the E/I ratio to the way they seal up..

My heads will allow a std Type I Turbo system to bolt right on, and they will staye sealed off- and hopefully without any extra studs!

I have Turbo combos- But I have never perfected one, and thats due to the exhaust port that VW gave us- its truly Satan!

[Sammy]

I really got to ask, did that person who told you that you can't keep the heads on have any real experience with turbocharging a type 4 or was he just talking out his ass like most people when it comes to turbocharging?

The reason I ask is that I absolutely do not agree with him at all. I see so many posts and opinions about turbocharging that are bogus it amazes me.
Someone reads a book or article on the subject and they instantly become an expert on it.

I don't consider myself on expert on the subject but I do have knowledge backed up by research and trial and error. Real world experience.

I tend to listen to guys like Jake and Evil ED much more than I would someone who just studied the subject without actually trying any of it.

That's the problem I have with college business professors, most of them are just regurgitating what they read and have no real life experience. Oops, went off on a tangent.

The limiting factor when turbocharging a type 4 is cooling and head design, not the head studs. Maybe if some fool tried to run 2 bar or something it might be an issue.
On my engine I didn't have any head leak problems and I didn't even run head gaskets. I just lapped the cylinders to the heads and that worked up to .7 bar boost.
The head port design is not optimum but a turbo will actualy compensdate for this poor design up to a point. Boost will make the heads flow more, it will even make the stock cam work very well up until the valves float. But it creates lots of heat in the form of back pressure and the heads have a hard time getting rid of that much heat.

Keeping the combustion temperatures and the head temperatures and oil temperatures down are key to keeping it alive.

If you can prevent pinging and keep the temperatures down the thing will run and run.

In my experience around .5 bar is the sweet spot for a non-intercooled 914. That's where it seems to work very well without overstressing anything or creating too much heat. You can go over that but then you start getting closer to the ragged edge.
With enough cooling and if it is rich enough to control pinging and combustion temperatures you can run it up to around .6 bar reliably on pump gas without having to back off very much on the timing which can acutally create more heat if not done right.

[andys]

I wonder how many folks here actually have driven or ridden in a turbo 914? I had a '73 914 turbo back in '74 or so. Very torquey, and plenty fast enough to make it a fun car on the street. It really did transform the car without spending a ton of cash. I seem to recall boost was somewhere around 6-8psi. So I wonder how much faster would one want to go and compromise reliability with visions of big HP? I suggest perhaps one consider what to expect from a flat four air cooled pushrod motor, and stay within it's logical (read reliable) potential. You want 200+HP, then maybe an engine swap/conversion is your next (big) step.

As an aside, back in '69, I built a 6 cylinder '69 AMC (Rambler then) American with a T4 Air Research turbo with alcohol cooling injection. Originally ran 4 psi boost, then bumped it up to 8 1/2 psi. I put 75K miles on that car without one mechanical problem. Surprised a lot of people with that sleeper!!

Andy