"Old" H-O TurboForce 400 makes 744lb-ft, 537HP
 

If you haven't seen it yet, check out this article in the current issue of Car Craft magazine. It is also online at:

http://www.carcraft.com/techarticles...ild/index.html

744lb-ft@3400, 537HP@4400

Ken Crocie told me about this build, the testing problems and fixes a few months ago. You can see that it is pretty much identical to the original H-O TurboForce shown here:

http://www.originalho.com/TurboForce.html

Don't ask: the "revival" project is done with no plans for commercial resale, but the I still own the "TurboForce Revival" Bird and there are a few others around, some Machos, some not.

I notice it says the engine needed a cam button to prevent cam walk with the roller:rolleyes: i wonder if that's just a generic Chebby caption.

I'd like to see that setup with a big intercooler.

No cam button of course.
 

Obviously, gotta be a generic caption!

You'll note that there is room for a custom intercooler in place of where the A/C compressor usually would live. I thought about installing one during the early stages of the revival project, but once we could not locate the pressure hat ("bonnet") tooling, I dropped any grandiose plans.

Its good to see the kit on the dyno. It could use a much larger turbo and meth injection would help. 60mm is tiny on that large of an engine, but it still made very good numbers!

It's a shame about the hat tooling. The engine looks awesome.
Will it be installed in a car?

Installed? According to Ken it depends on the owner's health. Right now, probably no, as I understand it. It is a 4-speed car anyway, so that would be a handful in the best of situations.

Unfortunately, a "much larger turbo" will NOT fit in the P-side confines of a stock chassis of a Gen-2 Firebird and the space constraints of the timing cover and fan on the D-side. Remember, the TurboForce kit was designed and sold as a bolt-on setup which fit with ALL accessories including A/C but excluding the HD alternator (due to the idler pulley).

We used to sell a water injection (which you could mix with alcohol or whatever you wanted) unit as an option. That did help. With the original Rajay 301E and open exhaust, 15psi boost was usually seen. Of course that would be way off the sweet spot of the turbo map.

Craig.........couldn't a hat from a ProCharger or something like that be used with the turbo force?

Larry,

If you changed to a Holley carb and possibly bulged the hood there are some commercially available choices. For instance, the "Extreme Velocity" hat looked like a good design but it needs a no-choke Holley and a bulged hood for sure.

The T-F hat is the only one I know of that works with a stock configuration QJet and also fits under a Gen-2 Bird hood. And that was the whole point of the TurboForce design.

Nice build up Craig. Thanks for letting us know about it. I am surprised though Ken used such a large arm with that late 70s block. As you know, a blown engine with a rod ratio like that puts a lot of strain on a not so strong block to start with. If that is a numbers matching T/A, that may be a mistake risking the value of the car. I realize it was a customer build and not his own so that was probably the customers decision and he will have to live with it. Hope it stays together and hope the customer understands that.
How many guys have split natually aspirated 400 blocks with 4 1/4" stroke already? let alone a blown version with even more arm?

Steve
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I figured a lot of people would start thinking about re-engineering this thing. Remember-it's a restoration job. I had to use stock numbers matching block , heads, ex. man. etc. So to make it more of a sleeper, I modified the unseen stuff. Why 4-1/2" stroke? Because I could. I couldn't change the block , but fortuneately the 78 stick block is a XX casting which a re-do of the 70-74 thick main casting.I knew i was going to be limited on peak HP because of the turbo size and stock ex, so I went for torque. Too big of a cam-with 489 cid--I don't think so -especially since it provided a 750 RPM idle with 18" vac. Throttle response was instantanious--no noticeable turbo lag. I ran the engine in manual mode on the superflow and saw over 800 lb/ft below 3000 rpm. CC published what was recorded by the superflow computer. My goal was driveability and big power. The car it is installed in has 3.42 gears and a 4/sp.

the XX block is a thick web casting? good to know, i usually never saved anything older than 71 unless it was a 55.

I didn't think it was in a car.
I bet it would fly with a 2.73 gear

Great Job Ken!, I met you at Pontiac Heaven and we talked for a bit about these setups, it was nice to see it in a magazine! We haven't had any trouble with the 4.5 stroke in 400 blocks at all up to 750hp and Boosted version is easier on parts than a high RPM NA deal, and this engine did pretty well and the Owner should be very excited! one day you should talk more about whats needed to use a Q-jet for Blow THrough!, Thanks

Nice job Ken Crocie!
 

Nice job Ken! Nice article too. Probably worth those nearly sleepless nights.

Since this article came out, I have had the chance to show two out-of-state guys who were by my place for other reasons my TurboForce Revival Firebird. Mostly the response was "wow!", particularly when I told them they could buy the current Car Craft and see one just like it, but BETTER.

And just to be clear, Ken did ALL the work and sorting out on this one. I am only trying to answer design and original engineering and manufacturing questions, which was my main involvement, along with Ken, back in the late 1970s. Of course "TurboForce Revival Project" questions too.

Craig

440GP69: U probably talked to Craig @ Pontiac Heaven about turbos, since I've never been there.

Soon as I figure out how, I post the TQ and HP curves. You have never seen one like this

Yes, the late hi-po (TA 6.6) block is much stronger than the std 77-78 400 block.

Great write up, and very nice numbers working within some very tight constraints.

Quote:
Originally Posted by KEN CROCIE
The car it is installed in has 3.42 gears and a 4/sp.

I didn't think it was in a car.
I bet it would fly with a 2.73 gear
================================================== =======
Ditto, and add this thought: I'd like to see a chart of Stock-steel Ring//Pinion Strength (12-Bolt, 10-Bolt 8.2//8.5) to figure where the Pinion-ratios reveal the weak Pinion or the weak Ring gear when installed for Race.
In other words: I suspect a 3.31:1 is much stronger than a 2.73:1 (pinion susceptible)or a 4.56:1 (Ring susceptible)....stock steel gears.

I am probably wrong here but when looking at that picture with the turbo, are the spark plug wires on correctly?? 18436572 something looks wrong, i see no.2 wire and follow it to the front of motor now i see the boot to no.2 but now look at 6 & 5 wire,s?? Its probably just me.