2110 Compression Ratio Suggestions

danimal · Post by **danimal** » Thu Nov 01, 2001 12:17 pm

>>>why does someone have to run STOCK ignition timing on a NON-stock engine?<<<

john, you STILL don't get it... the object is to test ALL timing settings for the one that produces the best results, for it's intended useage.

so if you stupidly build a motor that doesn't allow that on pump gas, how do you know what the full h.p. potential really is?

>>>Hey Dan, you really have a way of pissing someone off, glad you have alot of "Friends" out on that coast.<<<

jake, despite the fact that you don't know the difference between a hall effect sensor and a knock sensor, i still think that you are a hell of a motor builder

>>>I'm constantly having to prove people wrong, get on the list.<<<

steve, anybody that is an i.t. major has my respect... i just wish that you were more honest with people about your design failures.

dan
oceanstreetvideo.com

[This message has been edited by danimal (edited 11-01-2001).]

Steve Arndt · Post by **Steve Arndt** » Thu Nov 01, 2001 12:23 pm

<BLOCKQUOTE>quote:<HR>Originally posted by danimal:
>>>
>>>I'm constantly having to prove people wrong, get on the list.<<<

steve, anybody that is an i.t. major has my respect... i just wish that you were more honest with people about your design failures.

dan
oceanstreetvideo.com

[This message has been edited by danimal (edited 11-01-2001).]<HR></BLOCKQUOTE>

-------

What is an IT major? Oh, information tech.
I am majoring in mechanical engineering.

I failed Calculus last semester. I failed a drawing class in seventh grade. Need anymore? I built a picture perfect bluebook low compression motor for my daily driver three years ago, it failed (to perform well enough).
My new motor is very nice. As soon as I have another design failure I will relay it to you.
Steve

[This message has been edited by Steve Arndt (edited 11-01-2001).]

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Nov 01, 2001 12:24 pm

Dan,
The electromotive system uses the hall sensor for the knock sensing capilities of the system. It makes adjustments to the timing, or warns you do makle the changes manually....Electromotive designed it to work with the hall sensor, and it does, even with TURBO.

WOW,
I really am amazed that I got that compliment, thanks Dan....

------------------
Jake Raby
Raby's Aircooled Technology
www.aircooledtechnology.com

Steve Arndt · Post by **Steve Arndt** » Thu Nov 01, 2001 12:30 pm

<BLOCKQUOTE>quote:<HR>Originally posted by danimal:
>>>why does someone have to run STOCK ignition timing on a NON-stock engine?<<<

john, you STILL don't get it... the object is to test ALL timing settings for the one that produces the best results, for it's intended useage.
<HR></BLOCKQUOTE>

The term is MTBT.
Minimum Timing for Best Torque.
It can only be determinted on a dyno, with knock sensing. I bet you have all that in place with your blow through carbs, right Dan?

Steve

danimal · Post by **danimal** » Thu Nov 01, 2001 2:38 pm

>>>The electromotive system uses the hall sensor for the knock sensing capilities of the system.<<<

per the electromotive tec manual:

"The Knock Sensor is a microphone that is mounted into either the engine block,
intake manifold or head. G.M. P/N 1997562 is recommended. Some other piezio
electric types are available but generally most of the one wire sensors from GM will
work."

piezo-electric transducers are crystal-based; therefore they are not hall effect devices... i have never heard of a microphone being referred to as hall effect device, but...

>>>The term is MTBT.
Minimum Timing for Best Torque.<<<

thank you... it's good to see that someone out here understands how to make maximum power.

>>>It can only be determinted on a dyno, with knock sensing. I bet you have all that in place with your blow through carbs, right Dan?<<<

lol... blow-thru carbs are the very definition of primitive... and since we don't yet have knock sensor capability, that's why i suggested using dave cormack with his ear to a broomstick

in reality, tho, people like roger crawford specialize in tweaking the timing for mtbt... and they don't have to worry about knock sensors, because they feed the motor enuf octane to prevent detonation at all reasonable timing possibilities.

and that's exactly why you must build a street motor with a low enuf c.r. to allow for tweaking the timing... or you'll never see the maximum power potential.

dan
oceanstreetvideo.com

JohnConnolly · Post by **JohnConnolly** » Thu Nov 01, 2001 2:42 pm

I'm "only" an EE, but was ME in my 4th year when I switched to electrical. I think that gives me a pretty decent background in fluids, heat transfer, and thermodynamics. I only stopped my math curriculum after completing calculus 5. Probability and Statistics is another area that is VERY difficult to comprehend; intuition of problems often leads to the wrong answers.

What technical and/or math degrees related to automotive engineering and/or theory do you have Dan? We are all ears.

John Connolly
Aircooled.Net inc.

James2 · Post by **James2** » Thu Nov 01, 2001 2:50 pm

No, you did the same thing I did. I jumped from 7.3 to 7.6. It runs better and just as cool.

<BLOCKQUOTE>quote:<HR>Originally posted by Joe Boone:

I hope I haven’t done the wrong thing. I have a 1776, Duel Weber 40IDF’s, Stock heads (SH cut), Engle 120 cam and Empi quiet pack exhaust. When I first set up the motor I was convinced that 7:1 compression was the target, and this is what I did. It seems to run fair but I had to set the timing at about 38 degs to get it to run and it ran a little hot. This past weekend I decided to change my compression ratio to 7.7:1 (Since I had a bad oil leak that needed fixing anyway). When I disassembled the motor the piston tops were thick with carbon after only 5,000 miles.
With the 7.7:1 compression ratio the motor seems to run better and I’m running 32 degs max. advance. Am I looking for trouble? Will this help my carbon buildup problem?

<HR></BLOCKQUOTE>

JohnConnolly · Post by **JohnConnolly** » Thu Nov 01, 2001 3:14 pm

BTW, regarding those pictures.

1) 99' Chrysler; that's not a hemi, that's a heart. Note the quench pad above the valves. A conventional VW chamber is a "semi-hemi" if you ignore the two flat quench areas on the head, right?

2) 429 Boss; Same thing (two small quench areas). In addition, the valves are canted towards the center of the combustion chamber. so you are comparing a watercooled canted valve chamber with an aircooled chamber with valves on the same plane?

3) 356; again, we have a chamber with canted valves (around 30 degrees out of index from one another), so how that applies to a VW chamber, I have no idea.

James2 · Post by **James2** » Thu Nov 01, 2001 3:23 pm

<BLOCKQUOTE>quote:<HR>Originally posted by danimal:


building a high c.r. time bomb that is not capable of running factory advance on pump gas is nothing new<HR></BLOCKQUOTE>

Yeb, poor Jake. Building time bombs, then giving the longest warranty in the industry on them, longer then even the factory on new engines.

Guess, according to you Dan, poor jake spends all his time doing warranty work on his High Compression time bombs.

All I can say is those bombs must have 100,000 mile fuses on them. Because I don't see them exploding all over the East Coast.

Which is proof enough that High CR does work.

Steve Arndt · Post by **Steve Arndt** » Thu Nov 01, 2001 3:51 pm

<BLOCKQUOTE>quote:<HR>Originally posted by James2:
 Yeb, poor Jake. Building time bombs, then giving the longest warranty in the industry on them, longer then even the factory on new engines.

Guess, according to you Dan, poor jake spends all his time doing warranty work on his High Compression time bombs.

All I can say is those bombs must have 100,000 mile fuses on them. Because I don't see them exploding all over the East Coast.

Which is proof enough that High CR does work.

<HR></BLOCKQUOTE>

The time bomb comment was intended for me I believe, not Jake.
Point taken in jest though

Steve

JohnConnolly · Post by **JohnConnolly** » Thu Nov 01, 2001 7:57 pm

I'm very curious as to how the "experts" have concluded that 38 degrees is acceptable on SH engines, if it strays from the "engineering expertise" of VW that concluded that 30-32 is the correct timing setting. Also, where is this "30-32 total" advance that VW has recommended? I haven't seen this bulletin or spec in any shop manuals (St. Muir doesn't count).

I'm also curious as to why a 7:1 engine is "tweakable", yet any other engine with higher compression is incapable of "being tweaked". Why is this? Perhaps I'm missing something.

I find it ironic that the SH "recommended" setting strays from the mysterious "factory 30-32 setting" by the same amount (but in the opposite direction) as Steve's 2275. Did the Otto Engine God's drop down on this Earth and proclaim, "thou shalt run 38 degrees of timing on thoust engine" when the Semi-hemi head was developed?

Or MAYBE they designed the ENTIRE ENGINE, around this timing setting. Yeah, that's the ticket. "We'll run 38 degrees of timing, yeah. So, what engine components will work with this timing setting? Let's select a camshaft second, then move on to more important matters like bearings and gaskets".

Huh?

I'd like to believe that they designed the chamber, built the engine, then in tuning figured out that 38 degrees worked best, even better than the 32 degrees that was the "standard". What gives THEM the right to stray from the "norm"? Why is it OK for them, but "unacceptable" for someone else to try the same thing? That's called hypocrisy, and totally lame IMO. Let the envelope be pushed, shrapnel or not.

John
Aircooled.Net Inc.

Steve Arndt · Post by **Steve Arndt** » Thu Nov 01, 2001 11:10 pm

A fast burn chamber is where its at. If you have to run tons of ignition lead it says you are doing something wrong. Negative work. I know what works for me, and I know my NA 2276 would smoke your turbo Ghia. Lets race

I can run lots more timing but it is a baja bug that I really off road, so often I can only get OLD 89 octane gas at remote filling stations.
Steve

<BLOCKQUOTE>quote:<HR>Originally posted by danimal:
>>>I have already done the testing, on the dyno and on the street. I know what added CR can do, on both ends of the spectrum...Lets prove it...<<<

without knock sensors you haven't done squat, because you don't know when the engine is at incipient knock.

so you'll never be able to make the maximum reliable h.p. that a new car does.

and how do you expect to prove anything on a dyno without knock sensing capability? lol... jake, i suppose you could improve your stone age tuning techniques by putting someone out there with a broomstick against the side of the case... i nominate dave cormack

>>>on the said 2276 and drove it 750 miles round trip to SLC from Boise and back this August in 102 degree heat.<<<

yeah, but at only 26 degrees advance... sounds like another caveman using audible knocking to tune his motor.

steve, before you start screwing around with that engine, how about running a few tanks of race gas thru it, with the timing set at 30-32 degrees... i'd like to know if that engine reaches it's optimal h.p. when there is enuf octane to feed the compression...

why? because a 10-degree spread in timing over the optimal mid-point can change the octane requirements by 8 or more points... there can be a lot of power lost when the timing is retarded from optimal.

dan
oceanstreetvideo.com <HR></BLOCKQUOTE>

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Nov 01, 2001 11:15 pm

Its not a question of "Reinventing the Wheel" it can be better explained as "Reinventing the engine".

Dan, I bet you have the Blue book within arms reach at all times, and about 20 phone numbers of guys to call and ask questions..(don't call mine, you might get an ear full)

John, we need to find out who would be willing to "Meet the challenge" about this one...Lets put them to the test, maybe their best engine against ours. We still have not found anyone with enough balls to take up the offer on T IV Vs. T I and I bet we cannot find anyone for this one either....

Hey Dan, you really have a way of pissing someone off, glad you have alot of "Friends" out on that coast.

[This message has been edited by MASSIVE TYPE IV (edited 11-01-2001).]

JohnConnolly · Post by **JohnConnolly** » Thu Nov 01, 2001 11:24 pm

Dan,

why does someone have to run STOCK ignition timing on a NON-stock engine?

Also, in most non computer controlled cars, there is NO DIFFERENCE (this is an example) between an engine running 25 degrees and 87 octane, and the SAME engine running 32 degrees and 93 octane. As I mentioned before (you conveniently ignored it), you match the timing to what the engine wants/needs. This is why SH engines want 38 degrees, and Steves wants 26 degrees. Ignition timing requirements only give you an indication of what's going on. If I could set my correct timing to 10 degrees ATDC, THAT is the best possible scenario, but that's a dream.
The closer you can get to that point the better.

Steve Arndt · Post by **Steve Arndt** » Thu Nov 01, 2001 11:24 pm

Mr danimal,
my backyard hack tuning tools consist of a new Sun (sold by snap on) $24,999 5 gas engine anylizer/combo wide band O2 sensor. My father spends over $100,000 on tools to keep his import repair shop the best outfitted in Idaho. Ask around up here, he is hot. He helps me keep an open mind and not run in circles or reinvent the wheel. I have access to a chassis dyno, and I am saving for a flow bench and Dyno. Sitting next to me on the work bench is a set of CB dual throttle bodies, a Haltech ECU, an Autronic ECU, and lots of other new "high tech" goodies. I don't plan on using carbs for much longer. You won't see carbs on the engine when it blows by you down the quarter mile, although it could either way (carbs a fi).
Time bomb? Is your name Steve Hollingsworth? He told me face to face, in a year my "high compression" (what does that mean?) engine will be junk. I'm constantly having to prove people wrong, get on the list. Prepare to watch.

Steve