Getting to 60 horses

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Model T Ford Forum: Forum 2017: Getting to 60 horses
Top of pagePrevious messageNext messageBottom of page Link to this message  By Stephen Bowers on Monday, March 27, 2017 - 07:31 pm:

Looking for options to put out roughly 60hp from a T. Suggestions? Will need scat crank, etc. Either setup would use either a Carter bb1 updraft, or Stromberg downdraft(s). Also belt drive alternator, remove magnets and replace with slinger. 60 over pistons.

Option one seems to be:
high compression head (which is better; winfield, Sherman, Z?), 290 cam, bigger valves, model A+B intake and exhaust manifolds. Any guess what that combo would net power wise?

Option two:
New Rajo, 270 or 280 cam, dome pistons. Would have to make an exhaust manifold, intake would be the Rajo one.

What would be the best option for power?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Roger Karlsson, southern Sweden on Monday, March 27, 2017 - 08:06 pm:

A 5:1 Z head won't be enough for 60 hp, maybe a Sherman, since they're 8:1 (or at least the recently made ones were all 8:1) Top hp will be at more rpms than I would like with a std crank or a std SCAT, so a Model B crank installation or a thicker stroker SCAT would be preferred.

A RAJO or another type of OHV head would make it easier - but Les Schubert's method of widening the intakes to the max and create a division between the intakes for the cylinders and also in a homemade intake manifold would make the most of the flathead design.

Bigger valves and a hot cam is also essential.

You may want twin downdraft Stromberg 81:s like Clayton Paddison or maybe some exotic old updraft..

Red's headers used to make exhaust headers for Model T, but I haven't seen them in their webshop for some time? Model A headers should be possible to adapt to a T engine.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Monday, March 27, 2017 - 08:21 pm:

Roots blower? Paxton Supercharger?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eric Hylen- Central Minnesota on Monday, March 27, 2017 - 08:33 pm:

60 hp is a lofty goal. You'll be doing more tricks than you mentioned above. Check out the Tulsa club's website for good tech info. Here's a link to their dyno results page. You'll be most interested in the tests at the bottom. Don Cusack's 16 valve Roof head with Model A crank and cutstom pistons and rods delivered 51 hp to the rear wheels. Adjusting for driveline loss, should mean that the engine actually puts out your target of 60 hp. His car has amazing power and lights up the tires at will.

http://mtfctulsa.com/Tech/DynoSummary.htm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Fred Dimock, Newfields NH, USA on Monday, March 27, 2017 - 08:37 pm:

60 horses?
They produce a lot of horse manure.
It might be better if you get 60 mice!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Rich Bingham on Monday, March 27, 2017 - 09:07 pm:

The most practical way to get 60 HP from Model Ts is to own three of them. If you want 60 HP from a single vehicle, move up to a flathead V-8


Top of pagePrevious messageNext messageBottom of page Link to this message  By Stephen Bowers on Monday, March 27, 2017 - 09:13 pm:

I am looking for an engine builder to help me push the envelope on a T, old school "power" if anyone knows one please contact me. 455LOVELL@gmail.com

I have a lot of experience building SBCs, BBCs,and old alfa engines, but Ts (and flatheads) are new territory for me.

I am running 350 reliable horses to the wheels on a L4 2.0 engine. I am sure there is a way to milk 60 at the crank with a T block.

Regards,

Stephen


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tom Magee on Monday, March 27, 2017 - 11:43 pm:

Hi Stephen,

I like your thinking. Don't give up and keep us posted on your progress. Model T high performance, although somewhat oxymoronic, is a fascinating subject and one of my favorites.

A stock T engine has 177 cubic inches so 60 hp is .34 hp/in^3. That doesn't seem like much, however, the engine has several characteristics that CAN limit "high" horsepower. $$$$ and knowhow can easily solve these issues.

If you are not familiar with the incredible world of Model T speed equipment, you should check out the Museum of America Speed website. The Model T hardware is amazing. Here is the link: http://www.museumofamericanspeed.com/Inline-4-Cylinder.html

So aside from the super rare period correct speed equipment, there is a whole world of T flat head speed possibilities. As Roger mentioned in his post, Les Schubert has done some great work in this area with ported blocks and high compression heads. Of course, Les also has those trick 5 main blocks that let his engines revvvvvv.

Cheers,

Tom

fronty


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, March 28, 2017 - 12:39 am:

A counterweighted A crank drilled and pressure oiled will run at 4,500 rpm with no problems. Either the Prus head or Sherman work well as a flathead T engine. A Stromberg/Holley 94 or 97 carb works well. On a V8 they could provide 110 hp, so one should be sufficient. Bigger intake valves are nice along with a custom head gasket. Obviously a great camshaft and some methodical work to the intake manifold.
With this combination my old speedster would;
1. Slip the clutch at full throttle at 1,800 rpm. Over that it would hold.
2. I used stock T springs and the valves would float at about 4,500 rpm
3. It would run the car to 4,500 rpm with standard T gears (about 100 mph)
4. Frontal area was about similar to a 26-7 roadster body. So likely 60 hp anyway by my estimate
On my current flathead T engine I'm trying for 100 hp (hopefully 125 mph (I have H speed rated 19" tires))
I've shelved the 5 main blocks as the competition seems afraid of them and they make the rules. Besides with a cut down Ford "C" crank I get more displacement with the extra stroke


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tim Wrenn-Monroeville OH on Tuesday, March 28, 2017 - 08:43 am:

Why?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Tuesday, March 28, 2017 - 08:56 am:

Les, What ignition configuration are you using to run at 4500 RPM? I know from ECCT test data that a properly adjusted Model T coils can operate with Excellent firing consistency at 5000 RPM operating on 12V Battery but not sure how the magneto and timer would perform at that engine speed. I would expect the magneto output not to be of any limitation but a mechanical timer would be; what type of timer are using at that engine speed if not a guarded speed secret :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Andy Clary on Tuesday, March 28, 2017 - 10:23 am:

Yes you can make 60hp at the crank with a model T motor. Don Houseman made 51 at the wheels in Kanab a few years ago. The "Wild Cherry" hill climb car does far more. I think you could do it with a Sherman head but you would need a heck of a cam.


Andy


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kenneth W DeLong on Tuesday, March 28, 2017 - 10:48 am:

I second the why?? With enough money one can do almost anything except make sense.Why not start with a model A? Bud.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Chadwick Azevedo on Tuesday, March 28, 2017 - 10:50 am:

There are other options.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Tuesday, March 28, 2017 - 10:57 am:

Mike,

Not sure what Les will say in answer to your question. I would say that a cast iron flywheel, with magnets still attached, would be suicide at 4500 rpm!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Derek Kiefer - Mantorville, MN on Tuesday, March 28, 2017 - 11:01 am:

Why not? :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary Schreiber- Santa Isabel Ecuador on Tuesday, March 28, 2017 - 11:08 am:

I don't understand people asking "why". It is something that has been done and the OP wants to achieve that goal and is asking for options/suggestions. If any question should be posed it is what type of T are you building. It's a pretty sure bet it's for a speedster or racer not a TT or spindly old 1910 :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, March 28, 2017 - 11:16 am:

Tim & Kenneth. A couple of possible answers
It gives me a reason to get up and go to the shop !!
The others would be less kind so I won't say them

Mike
Ordinary point distributor has been easy


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Tuesday, March 28, 2017 - 11:31 am:

Jerry, good point! I don't think I would be too comfortable that close to a stock magneto running at 4500 RPM.

Thanks Les, that solution makes sense.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kenneth W DeLong on Tuesday, March 28, 2017 - 12:36 pm:

Les,Don't hold back.My thoughts were/are how will a model safely use 60 hp and what will break first? Bud.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Walt Berdan, Bellevue, WA on Tuesday, March 28, 2017 - 01:10 pm:

Well let me see - Why? His car his choice. I expect it will be a very non stock speedster or racer. People have been pushing these things for more power since they first hit the street. Better question is why not. I understand many folks wouldn't want to go there which is just fine. Just like his choice should be.

What will break first? Depends a lot on the design and implementation. IF something breaks we can all hope it won't e in a way that causes serious harm to him or others but that's the case for 20 HP in a dead stock T too.

60 HP is more than I need but I can certainly appreciate his efforts and wish him well.

I think it would be a lot easier to get 60 HP with a cross flow OHV rather than a flathead but in any case I'd be running a counterbalanced crank and full oil pressure.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Glenn W. Beers on Tuesday, March 28, 2017 - 01:33 pm:

Why not we started with a single cylinder 16 hp Kohler motor and made 33 HP for a tractor puller . Great fun !!!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Tuesday, March 28, 2017 - 03:39 pm:

Bud,

What will break first?

If Les did it, the answer is: the speed limit, (maybe the sound barrier too, we'll see).


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Tuesday, March 28, 2017 - 04:08 pm:

You could buy a 1932 Ford with a 60 HP V8 engine. The car was also built to handle the horsepower and has 4 wheel brakes. Those cars are also in demand, maybe even more so than Model T's. Then you can keep your Model T as Henry made it.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kenneth W DeLong on Tuesday, March 28, 2017 - 04:55 pm:

Jerry,My question was to the org poster and was not intended to disparage anyone.It's their T,Money,and Neck but i do wonder what will break first? I remember seeing a nice coupe with a 60 hp Ford V-8 but it had Model A axles,juice brakes,and A steering.It may be easier/cheaper/safer to just buy a Buick!! With a big grin-Bud.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan McEachern on Tuesday, March 28, 2017 - 04:58 pm:

For what its worth, the engine in Don Houseman's speedster is a very mild engine. Splash oiling, A cam and crank, BB carter updraft carb, not excessive compression ratio (9:1 or somewhat less). The cam is not huge in any respect. B Rajo heads flow very well in their stock configuration and this aspect alone makes a big difference. Just saying.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Andy Clary on Tuesday, March 28, 2017 - 05:25 pm:

As I recall Steve Nelson made around 49 go at the wheels with a Roof 8 valve and it is quite drivable. This is in a speedster, you don't need much power in a stock T. I doubt my speedster makes over 35 with a chaffin rajo, chaffin cam and a bb1 since I have a stock stroke crankshaft. My next engine will be big and should be in the 50 range with the extra size and compression.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, March 28, 2017 - 06:46 pm:

Norm and Kenneth
Actually '32 and '33 Ford V8's are 65 hp with the 1bbl Detroit Lubricator carb. Bumping to 85 hp with the 2 bbl Stromberg 48 carb in 34. I own a nice ' 33 3window coupe and while I own a restored Detroit Lubricator, it has the 34 intake manifold and the Stromberg 48 carb. The stock mechanical brakes work excellently when correctly adjusted
No stock T's have EVER been ripped apart for any of my speedster projects. There are WAY more components around than complete restorable model T's


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, March 28, 2017 - 06:55 pm:

One of the things I incorporated is a Watts clutch. It will slip before the rear axle parts are over stressed
Realistically, for me, it does not cost appreciably more to build one of these engines than a stock T. Yes, it requires more time. BUT I really enjoy doing it!!
Anytime you get in a car, the first requirement is to put the brain in gear. And drive within the limits of the car, traffic conditions and roads. It doesn't matter what you are driving!!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gene Carrothers Huntington Beach on Tuesday, March 28, 2017 - 06:57 pm:

Dan, How many HP do you have in your touring?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Derek Kiefer - Mantorville, MN on Tuesday, March 28, 2017 - 09:52 pm:

This T engine makes a little bit more than 60hp.



With the advantage of modern fuels and better fuel delivery, this one puts that 98hp claim to shame on that DO Fronty posted above... :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tom Magee on Tuesday, March 28, 2017 - 10:05 pm:

I think the DO Rajo is fuel injected. That's Dave Szumowski's artistry there. I would love to know all the details on the engine and car. There is a YouTube video this engine running on a test stand. This is why!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Derek Kiefer - Mantorville, MN on Tuesday, March 28, 2017 - 10:11 pm:

Yes, the 4 Winfields are throttle-bodies with EFI hidden inside feeding it E85. T block with B crank and 14:1 compression. He built 2 of these engines. The other is carbureted with 2 Winfield SRs and made 325hp on the dyno. :-) The EFI one has not been on a dyno.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Chadwick Azevedo on Tuesday, March 28, 2017 - 10:15 pm:

Stock engines are fine until you drive on todays Modern roads. Once you do you will find it is just as dangerous to travel at "T" speeds. Make a car that is safe to drive on modern roads and you are safer. Of course its always nice to drive on those quaint little back roads on a tour. Some like to be able to drive their cars period. Now the 1 off machined staggered valve overhead I saw for a T in a certain shop was a real beauty as it had been entirely machined from a single cut block of aluminum.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dave Hjortnaes, Men Falls, WI on Tuesday, March 28, 2017 - 11:38 pm:

Tom

Can you find that youtube video for us? Title?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tom Magee on Tuesday, March 28, 2017 - 11:46 pm:

For your viewing pleasure: The Szumowski DO Rajo

https://www.youtube.com/watch?v=A4hvvI4M4RI


Top of pagePrevious messageNext messageBottom of page Link to this message  By Rob Heyen - Eastern Nebraska on Wednesday, March 29, 2017 - 12:03 am:

Tom, Nice, thanks for posting.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Burger in Spokane on Wednesday, March 29, 2017 - 11:32 am:

Q. How did you end up with 16 cats ?

A. It was easy when you already have 15 !

Getting to 60 horsepower is probably just as simple. :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erik Barrett in Auburn Ca. on Wednesday, March 29, 2017 - 12:07 pm:

Stephen, 60 HP can happen in a T engine. We do it all the time. First you need to dispense with the T crank. It won't hold up. Model A, Scat crank or some other heavy duty crank and rods are a must. Since HP is derived from both torque and RPM, you will need higher revs to get there. This means overhead valves. These heads have much better volumetric efficiency at high RPM and higher compression ratios. This means power. We run an eight port Gemsa cross flow head on the Wild Cherry racer at 9.5:1 compression. Our shift light blinks at 4500 RPM but that's just an advisory. It the heat of battle we may have occasionally ignored it and raced on another grand or two. We have not dynoed it but it regularly beats 150 HP model A's. It helps that we are much lighter so we don't need as much power. If power is more important than money I have one of these heads for sale. It's a high strung racing brute and doesn't live until 2500 RPM. So yes, you can get serious power from a T. Like any high performance situation, speed costs money. How fast do you want to go?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gene Carrothers Huntington Beach on Wednesday, March 29, 2017 - 03:01 pm:

RDR always said a "Fast Car can always go slow but a slow car".......Always liked that idea
RIP


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Wednesday, March 29, 2017 - 03:35 pm:

Bud,

"Jerry, My question was to the org poster and was not intended to disparage anyone. ..."

Sorry Bud. Nothing disparaging intended. In fact I was complimenting Les' excellent workmanship & engineering. Sorry for the interruption.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kenneth W DeLong on Wednesday, March 29, 2017 - 04:01 pm:

Jerry Van,It took me 12 and 3/4 times to spell disparage right! With a grin-Bud.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Wednesday, March 29, 2017 - 04:29 pm:

Bud,

Don't think I wasn't impressed! ;O)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry Sherman on Wednesday, March 29, 2017 - 11:45 pm:

Stephen, I'm not an expert on building Model T racing engines but my Dad left me a ton of speed parts and I've gone very fast in Model T's over the years. He passed a few years back. Anyway, this is not the classifieds but I have several modified A cranks, a modified Chevy crank for a T (very stout but I'd never put a Chevy part on a Ford), a counter balanced A crank that needs shortening, several cam shafts of different grinds, high comp pistons, OH Rajos, a Fronty and a Gemsa. Some heads need a little work and others are good to go. Send me a PM for more info. Sorry sold the Gallivan a couple years ago and I'm holding onto my last few Sherman heads. I'll be at Bakersfield if you can make it. Jerry.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Rob Heyen - Eastern Nebraska on Thursday, March 30, 2017 - 12:05 am:

Gene, thanks for bringing Ralph into the discussion. He would have had his fingerprints all over this thread. And with his Great Races, he had the credentials. I miss him.

RIP


Top of pagePrevious messageNext messageBottom of page Link to this message  By Clayton Paddison on Tuesday, September 19, 2017 - 12:42 pm:

My '27 engine (with .080" pistons, 302 SBF valves, 300C full-race cam, Z-head and twin Stromberg 81s) Does pretty good hitting that mark..


Top of pagePrevious messageNext messageBottom of page Link to this message  By Cameron Whitaker, Oklahoma City on Tuesday, September 19, 2017 - 01:28 pm:

I'd bet the 60hp mark wouldn't be too hard to hit, especially with one of the more exotic overhead valve conversions. The Gallivan is a dual overhead cam head, and I hear it's a mean setup. It was first made while Ts were still being produced, so it's a period head. However, it cost more than a T new, so it was never popular!

The bottom end will need to beefed up to handle it, of course!


Top of pagePrevious messageNext messageBottom of page Link to this message  By john kuehn on Tuesday, September 19, 2017 - 01:42 pm:

I think I would go with a 30's or 40's era Ford if I wanted to build a hot rod.

To each his own.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Wayne Sheldon, Grass Valley, CA on Tuesday, September 19, 2017 - 03:31 pm:

So many years ago, Vic Sala had a dual fire Sherman head, on a tricked out block (I don't recall for sure what crankshaft?). I don't know what the horsepower was, but it was faster than most over-head valve engine T speedsters. Once, at the Calistoga races, he ran a few demonstration laps against a real modern sprint car (BIG engine, little car, airfoils) and the driver that at that time held the number two highest lap speed record on that half mile track (he had been the number one for some time until it was broken a couple months earlier). After the run, the guy said "I kept trying to get way ahead of him, but he stayed right behind me!"
I wouldn't be surprised at all if I found out that Vic's car made 60hp. I wonder if it is still around somewhere?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Cameron Whitaker, Oklahoma City on Tuesday, September 19, 2017 - 07:24 pm:

I think that we should all be encouraging Stephen. He wants to push a Model T engine and see what he can get out of it.

We should all be behind him for it. We are all Model T people. We all know what Ts can do, but it would be great to know what Ts WILL do! The T was an amazing car, and any tests that shows what it was capable of beyond its limits will just further support that. I know my touring can hit 45mph, but to know that a modified one can also hit 100mph on period hardware is just fascinating.

I, for one, am a purist. I like Ts as close to stock as possible (period accessories and whatnot are fine) but it's cool know what a T can do beyond stock. If nothing else, it interests curious spectators!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Stephen Bowers on Tuesday, September 19, 2017 - 10:37 pm:

Good Evening all,

Thought i would post an update.

Mike Bender is building this engine for me. I bought a new Rajo head, going to convert it to dual ignition with a modified Nissan truck distributor. Running a scat crank, custom pistons to increase compression, and full pressure oiling.

Best,

Stephen


Top of pagePrevious messageNext messageBottom of page Link to this message  By Stephen, South Texas on Tuesday, September 19, 2017 - 11:51 pm:

I hope he makes a video of the build. :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erik Barrett in Auburn Ca. on Wednesday, September 20, 2017 - 01:45 am:

Stephen, looks like you are well on your way to those 60 horses or more.


Top of pagePrevious messageNext messageBottom of page Link to this message  By William Hoffer on Wednesday, September 20, 2017 - 02:56 am:

Nitrous.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Joe Andulics on Wednesday, September 20, 2017 - 08:43 am:

I might be close?

https://www.youtube.com/watch?v=xQ9ibm3rRZo


Top of pagePrevious messageNext messageBottom of page Link to this message  By Pat Kelly Montana on Wednesday, September 20, 2017 - 07:53 pm:

At what compression ratio would pressure oil be required? Could you do just mains and rods with scoops? What cranks would hold up to 8:1 head?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Walt Berdan, Bellevue, WA on Wednesday, September 20, 2017 - 09:48 pm:

A Scat, Model A or Chevy crank can handle 8 to 1 as no big deal. I'd never go there with a T crank. Pressure to mains would suffice but may not even be necessary. A friend of mine runs a Sherman on top of a Scat crank with normal splash oiling. The feed holes for the mains were opened up some and there is an external oil line as well as the normal one. Several years now with no problems at all. This all assumes a typical RPM range in the 1,000 to 2,500 with occasional bumps to 3,000. More RPM would want pressure to rods as well as the mains. If you choose insert bearings instead of trusty babbitt, pressurize the rods and mains and include a filter.

I'm running about 6 to 1 compression using babbitt with an A crank under my Fronty with pressure to the mains and splash rods. My Datsun oil pump includes a filter fitting. Lower than an 8 to 1 ratio but no issues with oiling or babbitt for more than 10 thousand miles.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Sullivan on Wednesday, September 20, 2017 - 10:14 pm:

I hope he makes more than 60 H.P. Dave in Bellingham,WA


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kevin Pharis on Thursday, September 21, 2017 - 12:03 am:

I've been running a shortened A crank with a Datsun oil pump for about 7 years now. Full pressure oil to babbited rods and mains with no problems.

As for compression... 7.25:1 CNC cut and measured single plug Sherman head. That's actual measured ratio. But when you throw in the custom ground long duration, short overlap camshaft (also known as a RV cam) that simulates compression, the gage measured cylinder pressure is up around 180psi. That's closer to 10:1 ratio!! The hard part is preventing the detonation that threatens to push the crank out the bottom of the block.

Never had the car on a dyno but it sure had explosive power!! In low Ruxtell with 3:1 gears, when pinning the throttle the car would cut the tires loose at the bottom end and run to 4000 rpm in a hurry. That's like 65 mph in low Ruxtell!!

Realizing how destructive the motor ran I've since made camshaft/ignition timing adjustments to de-tune the motor :-(. It now only makes 160psi cranking compression and will run on 91 octane pump gas without detonating too bad.

In all, the A cranks will take a ton of abuse... You just have to keep oil in the bearings... Even if they are babbit. Pressure oil is more about higher rpm range than reliability. Hell, how long did it take chebby to pressure the rods in their 6ers? And they ran pretty good... Relativly.

The Datsun pump is great! Good pressure, reliable, built in full flow filter, and plenty of volume. Down side... Can't run a generator and it sticks out like a sore thumb. All in all I'm not takin mine off!!


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