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Horsepower, pre-1973: put your best engine on the stand, under a velocity stack, with no alternator, an electric motor turning the water pump, and a set of equal-length tuned headers dumping into 3-inch straight pipes, then play with the timing and AF mixture until you achieve the highest hp number, then correct that (add to it) to account for standard temperature and pressure at mean sea level. Advertise this figure as the horsepower of all engines in that series.

Post-1973 (OEM): Install engine on stand with stock air cleaners and housing and all accessories and belts, with stock exhaust manifolds and mufflers. Tune for max and advertise as before, using  smaller print.

OCCF: Pre-1973 x 1.18= HEADLINE NUMBER in Hot VW/HotRodder/Super Chevy/Car Craft/etc. “shootout” article.

Wheel HP: post-1973 - drivetrain loss and roller/tire slippage. Post on enthusiast forum.

@IaM-Ray posted:

They still serve as a comparison between builders at least and how the engines need at least 3500 RPM to get torque.  

Not necessarily. I believe all these engines were built specifically for this dyno run, where a peak HP number was the goal. These guys were all about the dragstrip.

My little 2165cc is pushing 141 lbs.-ft. at 3000. This engine was built to be run hard ON THE STREET. It pulls from 2500-6500rpm, like a diesel train.

These are the flattest hp/torque graphs I've ever seen. I can guarantee they'd be higher today.

This was an 009 distributor, and on 44IDF carbs too. Thanks again, Jake.

XLS Danny T1


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  • XLS Danny T1
Last edited by DannyP
@Stan Galat posted:

That was unprecedented, and a really cool thing. It gave everybody a chance to compare apples to apples

... but, it was run on Jack Sacchette's "somewhat optimistic" OC dyno.

It would have been neat to see what numbers they pulled on their own dyno’s before the shootout and compare them to Jack’s dyno.  

Years ago, Joe Aragona, of International Motor Shop, thought around 20% also.  For those that don’t know, cars powered by IMS have set NHRA records.  

@ALB posted:

In the VW performance world pretty well everyone else has thought that the southern California engine builders have been exaggerating their dyno power claims for any given displacement/combination- to gain customers and look like they are the best.  It's been going on since the '70's, with the East Coast people being the main force (maybe loudest voice is a better way of putting it?) behind the speculation.

I don't know who was loudest. But it was not mere "speculation".

@DannyP posted:

I believe all these engines were built specifically for this dyno run, where a peak HP number was the goal. These guys were all about the dragstrip.

This is the main difference between Raby and almost everybody else. Pat Downs is a national champion drag racer, but everybody knows (or should know) that he builds other, equally impressive engines. Everybody else? I'd have to see evidence to be convinced.

Regardless, Jake has never been about the drag strip. Everything he's ever sold has been about the mid-range pull Danny describes. When you get a Raby engine -- everybody knows what you have: an excellent engine, punching up at least 2 classes from what it's specs and numbers seem to indicate as a possibility. They're amazing to drive.

Pat Downs can build whatever you want. Want a peaky dragstrip champion (or dyno competition champ)? He can clearly help you out. Want an impressive street engine with tons of torque? He can do that too. With the engines he's building for Greg's Speedsters, he's showing he can build engines for reliability and longevity as well. The man really can do anything you want -- but it's very, very important that you be on the same page so you get what you'd like to have. As Robert pointed out, he's built thousands of these things, and designed the most complete head program the AVCW world has ever seen when he WAS CBP.

That he's a gentleman and really decent human is just icing on the cake.

@LI-Rick posted:

No BS numbers when everyone had to run on the same dyno.  These are some of the biggest names in the industry.  Hot VW's needs to do this again.  Pat Downs was top dog.

Thats never going to happen again , it took a massive amount of work at the time ,  and Dean  Kirsten  from Hot VWs retired years ago .

I believe the SAE HP  ratings  from the car makers was as said above without generator , fan etc , but the European DIN  HP ratings  were as installed ,

@Stan Galat posted:

I talked to Dean Polopolus about a Polo 911/4. For those of you not familiar, the engine is based on a 3.2L 911, with 2 cylinders lopped off. If I'm not mistaken, in 2008 a crankcase, a crankshaft, 2 cams, and a oil pump drive was $35K. Dean was playing with Alois Ruf and the Emorys -- he wasn't super-interested in a midwest guy with a clown car. He actually told me I was wasting his time, as I recall. I probably was.

It’s sad when people forget their roots.

@DannyP posted:

Jake got famous from his type1 work and certainly more so from his type4 exploits.

He was already noteworthy before the whole IMS thing.

My type1 was $6k(2002 or so) when everyone else was still around $4k or so. In my case, the premium was worth it. That motor is certainly more than bulletproof AND loads of power to boot.

I wouldn't trade it, it is a jewel. Even with all my modifications and changes I've made. I can build a motor, but he understands and experiments and KNOWS what combos will work.

My first experience with a Jake Raby powered Spyder was 15 years ago when I was at my first Carlisle event.

I was enamored with @DannyP Spyder and he asked if I wanted a ride in it...

All I could say was YIIIKES!!! :-)

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