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Mach1 Driver

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Posts posted by Mach1 Driver

  1. Posted · Report reply

    you can get custom pistons for $575.00 and have them mirror the combustion chamber so you make use of the entire quench pad on the head.

    .

    I was afraid you would say that ;)

    You recommended a Lunati 20350711  221/229  .549/.565  112 Hyd roller- mild performance street cam. Needs 5-speed or mild stall in 302 c.ii applications. Requires computer mods. Responds well to increased induction heads and headers. Likes 3.31+ gearing. 2000-6200 rpm

                    What about a Crane HR-220  220/228  .531/.552 114 Hyd roller- good low end and mid range torque and HP, good idle, moderate performance usage, 1600-5600, 2600-3200 cruise rpm, good w/plate nitrous system, 9.0 to 10.5 compression ratio advised. Also good w/supercharger, 20 lbs max boost w/8.5 max compression ratio advised

  6. Posted · Report reply

    Thanks, we're starting to get quite a list:

    215x65x15 is 26.0" dia and 8.5" wide, 4.25 backspace (no rub)

    225x60x15 is 25.6" dia and 8.9" wide, 4.25 backspace, lowered springs (no rub)

    225x65x15 is 26.5" dia and 8.9" wide, 4.25 backspace (no rub)

    235x60x15 is 26.1" dia and 9.3" wide, 4.25 backspace (no rub) edit: barnett has had on over 50 cars

    225x55x16 is 25.7" dia and 8.9" wide, 4.5 backspace, Shelby drop, (no rub)
     
    it's the second one down and the smallest diameter yet. Any more Shelby drop guys?

  7. Posted · Report reply

    OK lets talk about quench/squish. Its the distance between the top of the piston and the head in the flat area surrounding the combustion chamber. Barnett likes .035 to .042. Some forums say .040 to .045 and from one paper by an engine designer he said .040 was the sweet spot.

    I've been looking into the stroker kits and like the Eagle 14129. I want to keep the compression close to 10.0:1 so I'm looking at their dished pistons. At eaglerod.com they have a neat compression calculator. If I enter the data it looks like this for 351w/408:

    deck height           9.500

    bore                      4.030

    stroke                    4.000

    rod length              6.250

    chamber vol cc      58

    gasket thickness    0.066

    piston dome vol cc -20

    pin height               1.245

    compression          10.01:1

    deck clearance       0.005

     

    if you add the deck clearance and the gasket thickness you get 0.071 quench. I can get the quench down to 0.045" but the compression goes up to 10.57:1. I guess my question is- how important is quench, especially since I'm using dished top pistons? You just about need custom pistons to hit this number and get the compression you want.

  8. Posted · Report reply

    I am running 16x8 inch vintage wheel works rims with 4.5 inch backspace. Tires are 225x55x16 with the Shelby drop and 1 inch lowering springs. No rubbing. I think you should be good.

    thanks, that's very Interesting- look at the numbers:

    215x65x15 is 26.0" dia and 8.5" wide, 4.25 backspace (no rub)

    225x65x15 is 26.5" dia and 8.9" wide, 4.25 backspace (no rub)

    235x60x15 is 26.1" dia and 9.3" wide, 4.25 backspace (may rub)

    225x55x16 is 25.7" dia and 8.9" wide, 4.5 backspace, Shelby drop, (no rub)
     
    I checked these twice because I couldn't believe that the 15s have a bigger diameter than the 16. Well your tires are shorter by 0.3", and in the middle range of widths, and who knows what 0.25" more backspace is doing.
     
    It would be appreciated if more of you "Shelby drop" guys could give your wheel/tire sizes. Thanks

  10. Posted · Report reply

    That is because MSD changed their site within the last year and removed that info... If it didn't, I wouldn't have said it did.

     

    MSD TECH LINE 915 - 855-7123

     

     

    PERTRONIX III also claims multi spark throughout the entire rpm range but who knows for certain what it does.

     

    http://www.pertronix.com/prod/ig/ignitor3/default.aspx

     

     

    I get that you wouldn't have said it unless they had claimed it- and I appreciate that. Probably some over zealous marketing person. Their tech line says that all their ignition controls give it up at 3k.

     

    Pertronix seems to be another story---however it is buried in the distributor and doesn't have a clean tach output. Since I'm going to turn all timing control over to the FiTech that doesn't work for me. But if they can do it so can others, so I'll keep looking.

  11. Posted · Report reply

    Very nice, you're giving me muffler envy! I notice you have coil overs- can this be done with leaf springs? Seems like it might work if they went straight back instead of dumping behind the wheels. I wonder if the axle would hang down more with leaf springs when it is up in the air?

  12. Posted · Report reply

    yes, the msd 6al2

    The only reference to sparking on their website is under Capacitive Discharge Ignitions:

    The one short coming of a CD ignition is that the spark has very short duration. This isn’t a problem at higher rpm, but could be a lower rpm. However, engineers found that with the increased voltage and nearly instant recovery, the spark can be fired multiple times on the same cycle, hence multiple spark ignitions (or multi-strike, or second strike, etc…). At an idle there may be five or six sparks, and as rpm increases, the number of sparks decreases. Generally, most CD ignitions produce multiple sparks through about 3,000 rpm. Keep in mind that we’re discussing cycles that occur within milli-seconds!

     

    I can find no claim that the 6AL2 fires multiple sparks above 3k. I think its the physics of the thing- you can't charge the caps quick enough.

    I found this on another site: http://dtec.net.au/Multi%20Spark%20Ignition.htm

     

    Time Constraints on Multi-sparking:

    There are time issues and processor loading considerations when implementing multi-spark (time to calculate it and actually effectively do it).

    The burning mixture can be drawn away from the plug by turbulence and if fresh un-combusted mixture is present it may be ignited with another spark.  Research has shown that the sparks needed to be less than a couple of degrees apart to work effectively (you can see now where time issues start arising)

    If you start to consider the relationship between degrees, time and rpm you can understand the time constraints imposed.

    At 1000 rpm the crank travels 6 degrees in just 1ms (this may well be the time required to charge the coil up again). 1 degree pass’s in just 0.17ms!

    Its obvious multi-sparking can only be effective at very low engine speeds.

     

     

    With a 2 degree crankshaft window of opportunity to actually lite the mixture (If I did my math correctly) this would give you .111ms at 3000 rpm for a second spark, and of course it only gets shorter as the rpm goes up. So if someone is doing this I sure would like to know who.

  13. Posted · Report reply

    To summarize your thread: with a 4.25 backspace 215x65x15 and 225x65x15 don't rub. Barnett468 says lots of people run 235x60x15 but you have found some that say they rub.

     

    FYI from tiresize.com/calculator:

    215x65x15 is 26.0" dia and 8.5" wide (ok)

    225x65x15 is 26.5" dia and 8.9" wide (ok)

    235x60x15 is 26.1" dia and 9.3" wide (may rub)

     

    That being said, does anyone know if any of these would work with the 1" Arning drop?

  15. Posted · Report reply

    I like the Crane box better because it is digital (opposed to the analog MSD 6AL at the time I bought my box, they are also digital now.), and it's multispark pretty much the whole RPM range. It also has a better interface with dial wheels for RPM limits, rather than the MSD pin system. 

    I have the Crane HI-6 CD and LX92 coil. Along with the Crane optical distributor. It has pre-programmed curves that you select with a dial. No weights or anything like that inside it.

    I found this on Crane's website:

    Multiple Spark Duration 20 degrees crankshaft rotation below 3,000 RPM. Max 12 sparks per sequence with 1 millisecond interval between sparks.

    Does anyone know of an ignition box that gives multiple sparks above 3k?

  17. Posted · Report reply

    someone will ALWAYS have a car that is faster than yours or mine and it will likely be some import like a honda, so as long as i can roast the tires, i  really dont care if i am roasting them with 400 hp or 500 hp, and if i had a high horse car that had traction control, i would turn it off.

    .

     

    .

    agreed

  19. Posted · Report reply

    E85 is 85% acohol and 15% gasoline . You can run high compression with it like 13:1.

    Rereading that I did imply 15% ethanol, so amended it to say gas, thanks.

    So the question still remains- is 10.7:1 too high for 93 octane pump gas with 10% ethanol? Anybody out there run that combination? I read that 10.0:1 is the max you should go. I'm thinking your suggestion of custom RaceTec** pistons is still the way to go unless someone has experience indicating otherwise. 

    ** your post said "Race Rech"- can I assume you suffer from fat fingers as I do?

     

    I think Rsanter had a good suggestion- take the engine out, set it aside and build another engine that is a stroker. I think I'll do that and also set the FMX aside. I'll have to read-up on how to preserve them properly. On the other hand there doesn't seem to be much demand for a numbers matching 351w car. The big bucks go to big motors.

  20. Posted · Report reply

    Thanks fvike, that's very nice, and the video shows it all with engine, cockpit and pipes. We have 10% ethanol added here- do you also?

    I found this about ethanol blends:

    Ethanol has high octane and a strong cooling effect when it evaporates so it is inherently detonation resistant... BUT it also has lower energy value so the same quantity of ethanol will result in a leaner mixture compared to gas. The lean mixture can cause detonation despite the higher octane.
    A carb perfectly tuned for gasoline will need bigger jets to dial in A/F ratio with ethanol or ethanol blended fuel. Most setups are "close enough" to switch between straight gas and 10% ethanol blend gas but higher percentages of ethanol can throw off the A/F mixture a lot. Bigger jets would be needed for E85.

     

    FYI, E85 is 15% gas. I'm curious if anyone with a stroker here in the states has any issues with 10%?

    Most of the independent testing agencies have come out against E85 because it destroys fuel system components.

  21. Posted · Report reply

     Full lengths are out I don't won't them.

     

     

    Thanks Dave

    Sorry no help on the cpp box, but I'm curious why you don't want long tubes? I thought they were supposed to make it breathe better.

    Which engine do you have? We may have similar builds and headers will be one of my problems with a 351w and 4R70W trans.

  22. Posted · Report reply

    Fifty Thousand Miles out of an engine sucks?

     

    How many miles a year do you drive this car?

     

    Thanks again- I know you give rock solid information.

    It hasn't been driven much in the last 25 years (that's a long and truly tragic tale)...but if I could make it a daily driver again then maybe I would drive it 10k per year. At only 50k it would last less than 10% of its age (hey everything is relative- I bought this thing when I was a pup). I know LS1s in C5s that have over 200k on them (good old Mobil 1). Yes I know, I should put a LS1 in it. I have a Toyota with 150k on it- yes I know, there's no comparison. The newer motors and technology have spoiled us. If you want the old cars and lots of horse power you have to deal with the consequences, but dang it I don't have to like it!

    So you've given me lots to think about and research :) More questions will ensue.

  23. Posted · Report reply

    Appreciate the reply. but it's absolutely not the battery. And is DIDNT crank, that's why i replaced the neutral switch....

    OK, sorry when I read "click" I thought it was doing that all along. So all of the above. With the key off and in park or neutral- take a single jumper cable- yes you need a big cable- and clamp to the battery side on the solenoid. Clamp to the starter side of the solenoid- expect sparks. If it cranks (and since it already clicks) its a bad solenoid. 

    If it doesn't crank then disconnect everything, clamp to the battery + post and clamp the starter side of the solenoid. If it cranks the cable from the battery to the solenoid is bad.

    If it didn't crank disconnect everything and clamp to the battery + post and directly to the starter. That will be a fun test under the car- and don't touch the chassis with the loose end of the cable. If it cranks then the cable from the solenoid to the starter is bad.

    If it didn't crank then check your engine to chassis grounds. If those are good you probably have a bad starter. Take it out and apply power directly using two jumper cables.

  24. Posted · Report reply

    When you say they stop working do you mean they stop flashing but stay on? Put a voltmeter across the battery terminals when this is happening and tell us what you get- with both the engine running and not running. With the engine running you should get at 13-14v, ideally 13.8-14.2v. The battery should give you 12.6v before you put a load on it. It would also help to know if you have non-stock high amp headlights, if so you may need a higher amp alternator.

    As far as the grounds go, I remember my first car had dim tail lights- all I had to do is take the entire cast housing out of the sheet metal, clean off the rust and reinstall them. Be sure to check the battery cables- at both ends. I've seen cables with broken wire strands under the insulation that would test ok with and ohmmeter but since their wire size was effectively smaller than normal they couldn't handle a load.

    The flasher is current driven and some flashers work better than others in a low amperage condition (as the voltage goes down the amps go down with it). I'm sure someone on here could tell you which are best.

    I'm sure others will have brighter ideas.

  25. Posted · Report reply

    a stroker for your app will cost around $600.00 more than building a 351 which really is a small price to pay for the benefit.

     

    summit racing sells several stroker kits . the lowest cost ones are the eagles ans they are fine.

     

    they will wear the pistons and bores out sooner than a standard stroke will but that is the only real downside . you can get 100,000 miles out of a stock stroke . you might get 50,000 out of a stroker but there are exceptions to every rule.

     

    you need to run a slightly wimpy cam with fuel injection but that's what you need to achieve your idle goals and this can be compensated for with the gearing or stall converter.

    I've been looking at the Eagle kits but so far I haven't seen one with under 10.7:1 compression. Isn't this too high for the pump gas that tops out at 93 octane with 10% ethanol in my area?

     

    50k miles sucks. So if I don't stroke it and I live with the lope at idle...how does that change the equation? 

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