High speed/high rev rage motor suggestions needed.

All of the engines that we've done have been for either full tilt drag cars or full tile drag cars pretending to be street cars. Big strokers, big cams, lots of grunt but no power over 6500. Most recently we built a small "A.J. Sims" engine with his heads. carbs, cam and following all of his suggestions/instructions. That will "live" in the high 7's but not for long periods.

The new car has a just-built highway transaxle (very long gearing) and 215 75R/15 tires on very light weight Dragmaster wheels in the rear. I really need some good suggestions/specs on what to put into the engine to make it turn a nice strong 7500 rpm (or higher?) all day. I have an aluminum case and a welded stock case opened up for 94's and another welded case opened up for 90's to start the party. I've also got some high end ratio rockers and pushrods, a drop in stroker crank, a bunch of random various spec cams, lots of necessary bolt-ons, a turbo set-up, dual 40 Webers, single side draft 44 Weber, some Kads, a Holley (Performance) two barrel and Holley 390 four barrel with turbo inlet manifolds, a whole mess of dual and single intakes, a ton of tubing. some flat stock, a roll bar bender and a PISSA welder. Lots of stuff to get things rolling.

I can make ANYTHING, or machine the rest, but I DON'T have the knowledge or specs. I'd like the car to be very fast, not necessarily quick.

Any help would just be WONDERFUL ! ! ! ! ! ! and is totally needed. . . .

Thanks,

TC

That's a big open ended question. What do you want to do with this?
You have a highway geared trans but you want to spin 7500 rpm all day long? Where are you headed?

...it doesn't matter where he's headed as long as he gets there fast!

7,500 rpm...maybe put a rotary engine in there instead.

What are you going to be doing with the car 90% of the time? Build it for that and you will be the happiest.

I am not so certain that 7500 rpm all day is what I would shoot for. I built a 2332 that i have redlined at 7500, but even with a bunch of extra touches I can't think of why I would want to run it at 7500 all day. I have a 2.65:1 first gear, a .93 4th, and a 3.44:1 R&P. Runs 2815 rpm at 65, or at 6500 in 4th, 150 mph. I have had it up to perhaps 135 or 140, front end tends to get a bit light over 110 or 120. The car (Spyder) weighs in at about 1450 pounds...I built the engine with a high deck 6 shuffle pin case using 5.7" H rods, ceramic lifters, roller rockers 1.4:1, Nickies, JE forged pistons, did a lot of coatings including polydyne and ceramics with competition eliminator heads which I ported myself. Also did complete balancing to a nats eyelash as well as cryogenic treatments of all the steel parts. Running 48mm Webers IDE's. It develops more torque than one might well believe starting at about 3000 rpm and keeps right on pulling through 6500....7500 rpm in first by the way is 62 mph...gives a pretty decent 0-60 with no shifts...but it needs slicks as it is...time 0-60 is slightly under 4 seconds with 205 sticky street tires...I am generally pleased now that I have 5000 miles on this and it is broken in...next comes FI and see what that does....

This car, hopefully, will be for highway driving. Around town really isn't much of a concern, back roads will take care of themselves if I leave it in second gear. A watercooled engine transplant would be a far distant alternative, I'd like to stay with an aircooled VW based case and explore the limits of that. I have a LOT of engines parts, mostly hi-performance along with access to much more. I'd just be interested in gathering whatever knowledge you guys might have for building a high rpm strong long block, before hitting any other forum(s).

As I still have a boy's size three, I'd like to hold onto it as long as I can before exposing my ignorance on ShopTalk and getting reamed out to a man's size 12 for my trouble . . .

TC, I think if I had access to a lot of performance parts I would be inclinded to go to a 90.5 mm cyl dia, forged pistons, a good set of rods, what ever stroke was handy in my parts selection, set the compression ratio to 7.5 or 8.0:1, mild port on some 041/044 heads, do a good balance job, and do a turbo with a single draw through carb. With say 2 liters displacement, and only modest boost you should be able to get 220+ hp and not break anything. And such an engine, if you already have a bag of parts, can be done for not many $$$. And it should live a long time. I would go so far as to use hydraulic lifters and keep the rpm below 6000, and gear accordingly. If I had it to do all over again I think that is what I would do....I would also use TBI FI rather than a carb.....and you can always dial up the boost if you want to play with the big kids.... or dial it back down for driving to the church social....oh by the way, I really like 10mm studs with case savers for these sorts of things...

I don't see the need for the 7500 rpm's.
Go with bigger CC's
stroked
smaller turbo set-up (if in a bug=draw thru, speedster= blowthru-for neatness purposes)-smaller turbo will spool quicker and produce boost at lower rpm's. Draw thru=cheaper
1 1/2" header pipe=quicker spool
stock case
balance well
careful, quality reassembly
good to go
Stroked=more low end torque
shorter stroke=quicker revs, hp comes in at higher rpm

I love these kinds of questions, and I've got opinions. Mine mirrors Bruce's- forget spinning to 7.5K, make BIG power at 2.5K, and you'll be a happy man.

Torque Rules.

.... except for the turbo part. Turbos are great, but I know nothing about them.

Thanks for the help guys!

A little background:

We have a 1914 set up with a VZ-15, Mag 44 heads, welded case, a lightened flywheel and all the rest. It runs Webers and turns pretty good. It's fun in the short runs, but nothing going on really. I think that it's in the heads. Moderate sized valves and only a CNC program port job. Basically it's a "stand-by" drag engine, if the engine bays empty and we wanna play that weekend. Over the past Summer, we built a handful of smaller engines trying out forged 88 slip-ins, a variety of Engle cams, and smaller KKK turbos. These were a little more fun, but still lost out above around 4000rpm.

Then we tried an 1835, originally meant for the '55 Continental Coupe. Basically another welded case, drop-in stroker, forged pistons, This time we got some Mag 44 heads with big valves and custom porting. A lightened flywheel and a VZ-15 (I think) cam. I showed some real promise at low AND high revs, BUT when we swapped out the cam for an older FK-8 and 1.25 Scat rockers it came alive. We changed out the crummy rockers for some Pauter 1.4's and custom pushrods and THAT'S what got this whole thing started. When the little guy gets up in the sevens it's another world. It's a world that I'd like to stay in for longer than a few minutes at a time.

Thats what I want this time around. That's why I need the info. The process towards all this has been pretty gradual, I guess, and all the previous engines have each been a step closer. Good torque and fun in they own way, I'd just like to move the power band higher and get some revs and real speed this time.

Again, help and suggestions. Fear and awe.

Thanks !


Oh . . . forgot . . . yesterday a friend dropped off a VZ-25, VZ-35, cut lifters, and some "seasoned" 1.25 rockers. Will one of these cams help me out? I've no experience with either of these grinds. I'll look them up to see where the power bands fall, but I was hoping for some empirical knowledge here.

TC,

Don't want to mislead you. I wouldn't know how to stay 7k plus for an extended period (no previous experience). But personally I don't think it's required. You will need a bullet proof bottom end-that's for sure. The lightened flywheels are used for quiker rev's, in your case I don't think that's needed(could be wrong). Great rods!!!!!!
Trued case!!!!!Above you mention that the motors ran out of oomph.
I previously suggested a smaller turbo set up in order to lower your power band (and I still like that idea). If what you want is to rev it up, shift,shift,shift-1/4 mile style then a larger turbo is for you. Takes longer to get on boost but once there will still produce more air then your engine actually needs so it keeps producing boost.
Did you see the hot vw's Kawell turbo engine build. Very low tech, archaic even. But plenty of power using out of the box parts.

Bruce, thanks for the info and suggestions. Maybe 7,000 is unreasonable for extended high speed driving, possibly 6,000 is a more achievable goal.

I could be very wrong, but I'm equating high rpm with high speed. With the trans all set-up for highway driving (to the point of idiocy), and the tall tires on ultra-lightened wheels in the rear, I was hoping that simple math would help me out. 7,000 rpm would put me above 150 mph. The car wouldn't really be used for running to the mall, more to keep me "level", to chase away the late night Deamons in a way, I guess.

Making power under 3,500 or building an engine with torque, or utilizing a turbo that spools up quickly doesn't matter much. Once the car is out on the black ribbon, in fourth gear and climbing, I can wait as long as it takes to reach terminal speed. I'd just like it to be as close to 150 as possible. Maybe think of it as a dry lakes kinda thing.

All of our engines are well balanced, blueprinted, over-built and details checked twice. We tend to use lightened flywheels only because of the quick response, at any speed. They're best for drag racing, of course, but are still fun when hitting it hard to pass or catch up with someone. Plus, we've got more of those than stockers. I'm not worried about the build or balance, I just don't have the info to put together a parts list of what would be required to build a high rev mill that will live. Even if extended 6,500 rpm is the best that I can get, that would be a start. When I drive, I'm ALWAYS well past 3,500 rpm and now need to bring everything up a level or three.

PLEASE don't make me ask the terrorists over at ShopTalk . . .

TC, if you want to go 150 I don't think engines are the biggest problem....I think aerodynamics will be a bigger issue. As mentioned previously I have pushed my car to 140 mph+/- or there abouts, by the tach, the speedometer stops at 200 kph...the Spyder has a huge flat bottom and a curved top, makes a great wing at high speed. Wants to lift, to put it mildly. I also have owned 2 Speedsters, one of which I ran over 125mph frequently.

On the Spyder I know I need a large air dam / spoiler under the front of the car to lessen the air flow under and reduce the lift. Charmonix has a Spyder(R) redesigned for racing....I am not willing to make my car look like that for sake of the ocassional banzi run.....

Back to engines, you know far more about engines than many of us, so I am curious as to your "fishing" on this subject. No criticism intended by the way...just wondering "why"? More fun to discuss engines than some of the other things we get into anyhow.....

Anyhow, it would seem to me that 200 hp will push a speedster to 150 mph.... I am able to hit at least 140 in less than a mile, perhaps as little as 1/2 - 3/4 mile and I am guessing I have about 200 hp. As I recall the drag coeficient of the Speedster and the Spyder are both in the .3+/- neighborhood, depending upon windshield and tonneau(s) involved.

"I am curious as to your "fishing" on this subject."

Everything that I know about building VW based engines, pertains to drag engines. Lots of power and grunt for a VERY duration. If you wanted an engine that would keep up with a five liter Mustang from one stop light to another, I've got you covered. I need the info that I don't have . . .

Truly, I hate these sort of posts. "What is the best way to spend $1,500. on a VW engine?" and that sort of crap. You've already gone WAY faster in a VW than I ever have, I'd like to know how it was accomplished. THEN I'd like to know how to STAY in that mph range.

I've got the aerodynamics covered, I wanted mechanical info, but . . . there doesn't really seem to be any.

I'll let you all know what I learn from the "other white meat" out on the web. If I can't sit down when I return, it'll all be you guys fault.

Thanks anyway gang ! ! ! ! !

combustion chambers, 57cc

How do you go fast for a long time? Well, how I go fast in this car is pretty well spelled out in the earlier description of the engine. What I have learned going fast for a long time includes a several things I am willing to share...I am using a remote fan cooled 96 plate oil cooler, with a 2 quart Accusump, a deep 4 quart addional sump, remote filter, etc, for a 10 quart oil capacity. Oil temps normally run 180-210 degrees. During a high speed run, lets say 120 mph+ for a half hour, the oil temps go well over 240, I need another cooler...I had 2 96 plate coolers on my last Speedster and it was only about 160 hp and it did not get HOT, or over 220 even at high speeds.

The second thing I notice is transmission lube and the whole tranny for that matter gets very HOT, too hot to touch! Symptom is it beomes hard to shift. I have noticed this on 2 different transmissions after high speed runs so I don't think it is a transmission problem in my current car. I think there is a need for a small oil cooler a'la NASCAR on the transmission if you want to run fast for a long time. I am running synthetic lube in the tranny now, I didn't note any difference between synthetic and dino oil...

Third thing, the conventional gas tank is not large enough. I only get a useable 7 gallons out of mine...at over 120 mph I am down to about 8 mpg (not that I really ever calculated it closely, I didn't) but I did run out of gas on a back road and saw a gas station on the close horizon which I coasted into with a dead engine....tank empty....one thing that helps is to remove the stub VW uses in the tank to prevent sediment from being ingested...put a big filter in line....but you already know that....

4th thing, I need a robust electric fuel pump, I like Carter...I know there are very experienced people on this forum that contend a stock fuel pump is good to 200 hp. It has not proven to be so on mine....and I really do not like to go lean at 6500+ rpm...

And by the way, my car will beat me to death with wind buffeting at these sorts of speeds in pretty short order, not all that much fun to do often or long.....

I tried a dry sump on this car 2 times, one pump system by CB, the other by AutoCraft. Either has some good points and some bad points...if all you ever did was go very fast then Autocraft is the way to go, if you want to idle at a stop light with hot oil AutoCraft is not the way to go.... I think more cooling and ultimately a dry sump may be what I do, but I have to solve some other problems first. The CB system is ok for the $$ but not for serious work in my thinking....not enough oil pump capacity to keep me happy all the time....

I am using a WebCam 86A cam, running 9.5:1 compression, pump gas, about 28 degrees advance, works out OK due to the ceramic coatings in the heads and valves, no pre detonation.....the other big secret is the 5.7" rods, along with the nickies. I suspect I would have more heating issues with cast iron cyl's....the rod length is about as long as can be readily fit with the other components. Cyl head temps show about 300-320 degrees measured under the #2 spark plug durning high speed runs, dropping down to 290 normally when just driving...

Okay Jim, I have what is probably an amazingly stupid question (I know nothing about VW engines)...

How do you get the combustion chamber to seal when the head studs are passing thru the outer edge of it?
angela

Because the cylinders seal at the top portion not on the sides; so that means the cylinders will seal against the perimeter of the flat part surrounding the combustion chamber, not to the sides.

TC; you can always check with some of the folks in the forums at The Samba.com. I stress the word "some" because there's lots of a-holes posting on the forums too but there's some very highly respected builders and machinists with lots of experience who'll help you out.

Angela, not a stupid question at all, the edge of the cylinder itself seats firmly against the surface of the head ...all sealing is done there, none of it around the outer surfaces which are pretty well machined away as you have noted at the studs....as long as the heads are properly torqued, the cylinder studs don't break, you don't overheat your engine and distort something, and you have cylinders, and cylinder studs, that expand and contract at similar rates, all is well. If not, you can have a problem... It actually works pretty well if you lap the cylinders into the head surface before assembly and everything stays flat. Some people use a copper gasket, more often it is used with cast iron cylinders I understand. Aluminum to aluminum, all that is required is lapping.

"During a high speed run, lets say 120mph+ for a half hour..."

Wow! I imagine Texas is one of the few places you can maintain 120mph+ speeds for 30 minutes (covering 60 miles) - I need to move to Texas! (first, I need a car that CAN GO 120mph - let alone for 30 minutes!)

You guys are crazy!! In a good way, by all means, but crazy none the less. And keep it up, as I am learning a lot here.

If you go west of San Antonio on I 10 the official speed limit goes up to 80 mph for very long lengths of road until you get close to El Paso, like nearly 400 miles. Traffic is usually running 90-100 mph so going a bit faster, particularily between say midnight and 4 am, can be done for a long time. Trucks are off the road mostly, police protection is low, the deer are usually asleep, and you can see headlights a long way. Not that I would ever suggest doing such a thing, or ever do such a thing myself...just an observation, mind you (:>)

Jimbo - must be the outlaw in ya!

My last experience on I-10 past San Antonio; Years ago a friend in D.C. sent me money to buy an 83 Targa he wanted. So my wife and I decided to drive it back East to DC for my buddy (road trip). Driving through Texas I asked my wife Ginny to drive while I caught some Z's. We traded seats and I dozed off. Minutes later (?) a bump in the road woke me up and I looked over at my wife who had a huge grin on her face - I looked at the speedo. She had the CRUISE CONTROL set at 110 mph. I told her "...110!! Babe, you ROCK!!"

That was a fun road trip!

outlaw, who me? I beg to differ, this is just your little 1200cc 40hp motor....

COOL! I like the look of that car!

Talking about high speed; I was on the highway on my Speedster after 2 am last night and decided to try how fast it would go. The mildly modified 1915 cc with 3.88 transaxle was able to push the car over 90 mph; I was driving with the top down and decided to quit mashing on the pedal (because the thing kept going faster and faster) for fear of getting a speeding ticket or losing control on the thing at that speed. Remember the "1/4" of fiberglass between you and eternity" quote?....

...but WHAT a ride that musta been!! WOO HOO, Ricardo!!