Head Mill/Squish

[Cowtowner]

Did the shop that did your heads CC the combustion chambers or machine them to stock or desired volume.

No they didn't. I could have cc'd them but as noted above, chose not too.

[Cowtowner]

Personally I would stop what you are doing and back up and start over. You have no clue what your compression is, but you was to add more performance parts. Getting the heads CC'd and the pistons at zero deck so you know what compression you have will return you more than anything you do with the intake.

The only unknown is combustion chamber volume (I know deck height, dome volume, gasket thickness). Assuming 85 to 87 cc, that runs 10.4 to 10.6 on a calculator. Presumably it's on the lower end. Isn't that close enough to decide what air cleaner, throtttle body and mufflers to run?

You have been given fantastic, solid foundation advice from all here. You chose to ignore it.
Carry on.

I am carrying on and I have appreciated the advice that people gave me. I had just asked whether I could trade my two air cleaners back and forth (i.e. is there much of a difference, tuning wise, between the two) and whether people thought the OEM throttle body and SE mufflers were good for a build like this.

If I need to know the exact combustion chamber volume before people can give any further views, so be it.

[harpwrench]

It's not a big deal on the cc's for what you're doing just check cranking compression and go from there if you think it's lacking something. I wouldn't think that a 58mm TB would gain anything for you. Changing from the heavy breather to the standard type AC can definitely change the VE tables, can you get away with it, yes it's not going to blow up but it's not really proper if you're wanting it to run its best.

[rigidthumper]

I'd tune with the Heavy Breather installed- IME, it's slightly better in the midrange, than the normal hi-flow AC, and the onboard O2 system can compensate adequately downward during cruise conditions if you decide to swap AC units later.

[kd]

    If you already have this selection of breathers you can swap them out at the tuning session and actually see how they work or effect AFR.  Most tuners will take the time (at least on larger builds) to remove a breather / filter to get a measure of if the breather is holding anything back (usually only on WFO performance though)

[Cowtowner]

Thanks all for input on air cleaner - I think it makes sense to have it tuned with the heavy breather (I like it better but sometimes like running the football too). Good idea to have the tuner do a run with with the hi flow to check the difference from the heavy breather - I'll ask them if they'd do that, pretty simple to change them over. I'm plumbing the external breather in the same configuration on the heavy breather as it is on the hi flow - with 1/8 NPT x 6 an fittings in the comparable location so it can easily be switched from one to the other.

Sounds like on a fairly mild 103 build like this, the throttle body may not be worth it and I've been watching spending. I'll probably drop that idea.

The street cannon slips on seem to be about 1 7/8" baffle although I can't measure them very well. I'll probably run that one by the tuner to see what they think - it seems to be running strong and I'm not after the biggest numbers, just something that makes decent power and runs good.