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quite a few sets of Johns pistons have made it into the TI world and there have been some mixed results with high CR and pump gas.

For a while I been researching the use of a "squishy" piston and have came up with some engine configurations that seem to be heavily optimized by the use of this design of piston. This is complimented by a certain STOCK Type IV combustion chamber shape.

when one builds and engine with the properties of a "Squishy" design the entuire engine combination changes. The cam timing, ignition timing and etc must change to accomodate the added efficiency.

With that being said I'm going to unveil my newest bit of R&D here. I have placed an order for 2 sets of Johns pistons. One set of Type Is, and a set of 96mm as well. I will be using the TI set first in the 2165 TI test engine that I have been using for cooling system testing. It is VERY tired and needs that inferior case swappped out for a genuine onee before I can go the last level of DTM Type I testing to get it perfected. I will attempt to keep the combo on this engine exactly the same since the cam profile it already has is very close to being squishy compatible. This will increase CR from 10:1 to around 12.2:1. Thats about as much of a direct comparison that you can get... Then I may swap a few cams and etc to see what the effects are with the same CR and a different cam.

The mac daddy is gonna be the Type IV version of it. For this one all I'll be doing is going is creating a "squishy 2270" The combo will be VERY close to the standard 2270 "C" version that has proven its powerband to be spot on since 1997 with only slight tweeks to the cam and heads. I have over 300 dyno graphs from 2270 engines to compare the squishies with!

I will be opening up the lobe centers, and basically keeping the same cam characteristics, but bumping CR from 9-9.5:1 up to around 11.8-12:1 with the same combustion chamber particulars and port work. I'm sure it will take me a good long while to get it absolutely perfected, but I have some good combos in my head that I will be trying as soon as I get the pistons.

I am in the process of buying another 912E to install this engine in to and use for testing. The 912E is so simple to rip the engine out of and has so much room that it is a perfect test car. It also has good gearing and is easy to lug with 5th gear to listen for pings. I will also incorporate my safeguard from the dyno into the vehicle to watch for detonation and overheating..... The 912E is also heavier and tends to heat engines up in 5th gear pretty good on a Georgia hill.

Its my hopes to have this perfected before my new heads come out and I have to start all over again with combos and cam profiles...

I'm getting excited! At this rate I'll have to stop assembling engines and just do the crazy ones and test stuff all day long!

SHOOT ME NOW!

Cannot wait! Stay tuned, same RAT channel!

Does this mean I can send my pistons to you?

Ask John... Yours might be a tad different.

I'm glad to hear this Jake. I have felt all along that the squishies were promising for the T4 simply because John was there to help. Unfortunately "Its all in the Combo" as you say, which means few things are really just a bolt on improvement, but between the 2 of you I am sure you will get results. From what I have gleaned from the forums the squishies allow more compression and run cooler. These are 2 GOOD things, right?

Go for it
Ron

MASSIVE TYPE IV wrote:I will be opening up the lobe centers, and basically keeping the same cam characteristics, but bumping CR from 9-9.5:1 up to around 11.8-12:1 with the same combustion chamber particulars and port work. I'm sure it will take me a good long while to get it absolutely perfected, but I have some good combos in my head that I will be trying as soon as I get the pistons.

If you can build a reliable T IV motor with 11.8:1 c/r, I will be very impressed. I just went to the Porsche web site and found some technical specs of their 911 GT3 and Carrera GT models. These cars obviously use sophisticated engine management systems to produce this kind of hp using ~ 12:1 c/r.

911 GT3

Engine

No. of cylinders 6

Displacement 3.6 liters

Max. power (DIN) 380 hp at 7,400 rpm

Max. torque 285 lb-ft at 5,000 rpm

Compression ratio 11.7 : 1

----

Carrera GT

Engine

No. of cylinders 10

Displacement 5.7 liters

Maximum power (SAE) 605 hp @ 8,000 rpm

Maximum torque 435 lb-ft @ 5,750 rpm

Maximum engine speed (revs) 8,400 rpm

Compression ratio 12.0 : 1

Alpine,
I'm not out to impress- I'm out to PROVE.

This will definately be a learning curve, didn't I stress that above??

Its a new idea, the name I chose for my shop was "Aircooled Technology". The name speaks volumes in its self....

do less reading, and more building.... Any experience with wrench in hand is better than sitting around reading specs.

Just because a big name auto maker does something or doesn't means nothing to the engine design that I'm trying to manipulate...

Hel, Porsche/VW was the ones that outfited these engines with the worst camshaft, worst EFI and etc that we have overcome to get the power we are now while running cooler than stock get better fuel economy and if done properly will last just as long...

You took my post wrong - I wasn't being skeptical or sarcastic, I just said that I would be impressed. I vaguely remember that sometime back in the eighties while most every other manufacturer was using 9 or 10 to 1 compression ratio, Jaguar had a cylinder head design that allowed them to run 11:1 c/r. I was impressed with that back then too.

And since I don't have a dyno or the facilities to build and test multiple engine configurations, reading and simulating them is the best I can do. I just want to build myself one good one.

P.S. When can you test the MPS for me?

Another thing to consider when making that comparison between a modern Porsche engine with the T4s going in our 1950 to 80 cars is emissions. You can play lots of games with cams to boost usable CR (and HP) without much concern for emissions in an older car.

I'd imagine that a modern otto cycle with engine management that didn't have to meet emissions requirements could bump CR up to the 13 to 14 range and maybe even higher with new direct injection systems hitting the market now.

Regardless though - considering that there are thousands of VW fans out there that think its impossible for an engine to live above 7:1 CR, it would be an impressive feat to run 12+:1!

I honestly hope that I do have several issues by running the high CR. It will help me to find the absolute highest CR that each combination can stand. I learn more from failure than from an accomplishment!

Compression has been my best friend, and the one thing that has given my engines and edge. Cooler running, better MPG, better power are just a few things that being able to effectively use CR has done for me.

Its time to really bump it up, and hear it thump harder than ever before!

Yup, success just means you havent pushed the boundries far enough

Cya,
Sam C

Always been a believer in higher compression! Glad to see you are going to do some testing. Did you get the disclosure agreement worked out finally? (LOL)

The mac daddy is gonna be the Type IV version of it. For this one all I'll be doing is going is creating a "squishy 2270" The combo will be VERY close to the standard 2270 "C" version that has proven its powerband to be spot on since 1997 with only slight tweeks to the cam and heads. I have over 300 dyno graphs from 2270 engines to compare the squishies with!

I'm glad you picked the 2270. Youve done some outstanding work on your super heros, but they are out of alot of peoples reach, and lets not forget, the 2270 is your favorite engine!

Ron

Absolutely! One reason that the 2270 has come so far is that it is within reach and we have done so many that we have tried alot of different stuff. Almost every Super Hero" is radically different and none fall under a "version" category, so getting comparative data is tough- not so with the 2270.

I have hundreds of dyno graphs from 2270s.

How is the squishy work going? I just bought Alexs 102 nickies and am thinking about using squish pistons in my new engine. When will your new T4 heads be for sale?

Thanks,

Randy

Alpine, the numbers you posted are from WATERCOOLED cars!! you can run a much higher compression ratio with water cooling things off! Chevy and Ford have been running 11-12+ compression ratios for YEARS

I for one am totally hyped about the idea of squishies in a type 4! I think it will be awesome to hear and see! I can't wait to see the comparisons of dynos on the 2270s with squishies! great job Jake! and good luck!