Making the type four rev higher Options

[yeahmag]

I would completely disagree from experience. My Type I's never could take the same beating on the track that my Type IV's have. I build all my own engines and while I've progressed in my engine building skills over the years I still believe the Type IV has more capacity for cooling and stress than the Type I. What engine went in the later busses...? A Type IV.

[DBCooper]

Well, the T4 IS a truck motor, so it makes sense they'd put it in the vans.

There are only two significant advantages the T1 design has over the T4 for performance, first being the exhaust port design, but the big second is the huge availability of not expensive performance parts. For example you can buy all new aftermarket aluminum cases that are beefed up in all the areas where the OEM case proved to be weak, forged cranks in every dimension, h-beam rods, brand new CNC milled heads in any port shape you want, etc, etc. That means these days you can build an ENTIRELY NEW T1 engine with all performance parts.

I think you could probably build one to last, but that's not actually what I'm suggesting. I really just want to be clear about the actual needs, to make sure that the suggestions I make, that ALL of us make, are actually in line with the intentions and needs. If all you need to do is average 40 dependable miles an hour for 24 hours, for example, we may be overthinking and overspending all this. And the same's true to bump that up to just 60 mph, T4 or T1. So I'm just saying understand the really basic questions about need first, then the fun stuff (like spending Trek's money for him) later.

[ChrisFoley]

I averaged over 60 mph for 1000 miles the last time I went on a long road trip in my 914.
That should be a piece of cake on the track.

[Trekkor]

You said "we turned 322 3 mile laps in our 2012 24 hour race", which is an average of about 40 miles an hour. That's not real fast, so did you spend time in the pits? How much? A 40 mph average speed won't stress your engine, so I guess the real question is what's your real average speed, when racing, the speed you'd need to maintain for 24 hours?

Reason for the T1 suggestion was cost. All the performance parts you need are cheap in a T1, while the same T4 parts are expensive. The question about aircooled fours in endurance racing was because you're doing something really rare and difficult, so it's really cool. But it's so cool exactly because it's so hard. And since it's hard to make a T4 live that long it seems that your priority is probably longevity before power or RPM's. Or no? And IF that's the case (lots of "ifs" here) then that suggestion to go big and mild might be wiser than smaller and stressed.

Did you chop up the back of the car, or was it converted to upright cooling? If so what are you using? Is there a thread somewhere?

We spent at least 60 minutes in the pits doing fueling/driver changes and maybe as much as two hours for mechanical issues. Also, some lengthy full course yellows.

We had to keep the rpms' below 4500 the entire race or the valve covers gaskets would blow off ( drivers weren't paying attention and this happened four or more times during the race anyway ).

We had hard contact and had to change both driver side wheels that were broken.

I went out at 4:00 am and noticed the steering wheel was about to come off. had to limp back and get that tightened.

We fabbed up very ugly, yet very effective cooling ducts.
In 110 degree plus conditions the car never went over 190 degrees.


KT

[DBCooper]

What I think I am saying is that for power, I am not sure that the type 4 engine is the best example out there. Maybe if you have to have air-cooled, but even then I suspect there is more capacity in the Type 1. What is the icon for having said the wrong thing?

Yeah, probably not good to say. Trekkor's already invested in the T4, it's a solid engine, and if he never saw more than 190 degrees he's already figured out what I thought would be the biggest hurdle. Not that it helps any in this discussion (it doesn't) , but I like this photo of Funcars at Donnington Park:

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.funcup.co.uk-2618-1371157490.1.jpg)

So what were average speeds when you were on the track? Were you competitive with the class winner, or do you need to go faster? Don't answer that, EVERYONE needs to go faster, so a lot or a little?

For the valve cover gaskets you can weld a 1/4" strip of sheetmetal on the inside of the valve cover to form a channel so the gasket can't slip in. That together with a lot more crankcase ventilation and they should stay in place. Can't fix shunts, you'll tighten that nut, so put in a good sound system and go have some fun. 190 degrees? I'd LOVE to see your ugly vents.

Everybody's given good suggestions about lightening the valve train so you can rev higher. You've got a late model car, so what's the final drive now, do you know? 3.88? If not that's a possibility, and cheap. A built late model fine geared single sideplate trans (superbeetle) should be all you'd need. Their 4th is geared a little higher already (and they also sell aftermarket fourth gears) and you can increase the RP even more to a 3:44. That might be preferable to a lot of (expensive) engine modification, unless you already intend to do that anyway. For the final word give Fat Performance a call. They still build T4's for desert racing and sell the parts, so they should give you as good information as you'll get anywhere.

[Trekkor]

We missed our class win by two laps.

We were doing 70-100 on the fast sections.
Just limited to low rpm's in the first race.

We modified the valve covers and added better crankcase venting so we are getting there.

This last race, we were in 4th overall after 4 hours before we retired due to the split on engine oil cooler.

Here's a couple shots of the cooling ducts.
All parts were found at, surprise, Home Depot!






The air was directed from both sides and into a tee, that pointed right into the impeller on the motor.


KT

[stugray]

I averaged over 60 mph for 1000 miles the last time I went on a long road trip in my 914.

I drove my 914 back & forth from Oklahoma City to L.A. at least 5 times while in college.
70-90 mph from full tank to empty was the norm. 24 hours with 12 hours straight drives ( I had to sleep). However a 914 with just a driver is quite comfortable to sleep in at rest stops ;-). I would show up in LA sunburnt on just one side of my face.

Stu

[messix]

wow really guys (IMG:style_emoticons/default/slap.gif) ... you cant compare cruising down the hwy for hours on end as anything like RACING for hours on end!!!!

the stress that full throttle acceleration and full loading of the engine for hours on end is more like driving up a steep hill for hours on end!!!

[DBCooper]

That is SO cool. Well done. I don't know what else to say. Well, maybe "git er done!" That's outstanding. My son had that same bumper sticker on his slammed 72 144 in Santa Cruz. It caused a lot of confused looks.

It looks like you have things under control. Raising the final ratio in a T1 trans is easy enough. They were the original base for the Mendeola boxes so they're really pretty solid, and both Mendeola and Weddle have parts if you want to beef it up. The taller ring and pinion is something like $350. If you haven't had problems with the T1 transmission so far that might be easiest, but the 911 901 conversion has been done a lot so no mystery. I have no idea about flipping ring gears in a 914 901, but can't imagine that transmission is much different internally than the 911.

I also think you already know how to spin the T4 a little faster, but to me it sounds like you're actually there already, that your concern is more the endurance racing issues than more RPM's or horsepower. Give Fat a call, I think they can help, or point you at someone else who can. Even Weddle or Mendeola, that's what their customers do. Unless someone here has lots of T4 endurance racing experience and will chime in.

Good one, Trekkor. Looks like a lot of fun. Just to throw one more idea on the table I think you know Jeff already, with the LS1 244:
(IMG:http://www.914world.com/bbs2/uploads_offsite/i53.photobucket.com-2618-1371219002.1.jpg)

[sean_v8_914]

you must manage the FORCE
force = mass x acceleration
component weight x how fast you move it, RPM.
marinate on that . then imagine every moving part in your valve train.
22mm wrist pins shave over 150gm
nice set of rods shave over 150gm
light weight valve train will cost ya.
Obi wan will love you and yoda will make you live forever

[sean_v8_914]

lots of cool valve float videos on youtube

[Trekkor]

better view of the duct work!:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371235043.1.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371235044.2.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371235044.3.jpg)

Plus we have a thermostat controlled, front mounted oil cooler:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371235044.4.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371235044.5.jpg)


KT

This post has been edited by Trekkor: Jun 14 2013, 12:44 PM

[DBCooper]

Wow, reinforced bumpers welded on, looks like disc brakes on an adjustable beam, an engine protection cage/hangar, an adjustable splitter, stock Boge shocks, big ol' OIL COOLER!! All cool. I like the Home Depot furnace stuff, that big fender washer holding the scoops from the inside, and the welded fenders for aerodynamics (of course)! Dude! You guys are SERIOUS!!! Extremely cool. But where's that crankcase ventilation? And you really need some shark's teeth on those scoops.

So those wine country guys really let you race with them? But they don't let you beat them, do they? Some rule against that, right?

[Trekkor]

Let's see if i can find some shots of the ventilation...


KT

[Trekkor]

(IMG:http://www.914world.com/bbs2/uploads_offsite/i944.photobucket.com-1413-1371249768.1.jpg)

Fun video I found


KT

[sean_v8_914]

so I had to look at all teh pics on thet link, of course. extensive use of HD Racing parts...love it.
i assume it runs cool, right?

[sean_v8_914]

that breather box is qustom HDR. the electrical conduit fittings are to absorb the ion flux generated just prior to the jump to light speed, right?

[Trekkor]

Exactly!


KT