SMALL BLOCK FIRING ORDER SWAP - Moparts Forums

Register Log In Moparts Forums Unlawfl's Race & Engine Tech SMALL BLOCK FIRING ORDER SWAP

Print Thread

Page 2 of 2

1

2

Re: SMALL BLOCK FIRING ORDER SWAP [Re: Cab_Burge] #2665722 06/14/19 07:34 AM 06/14/19 07:34 AM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote a custom built crankshaft could remedy the issues, & on a side note there was something in FABO (iirc) about redrilling an oiling hole or holes in the crank journals to duplicate the chebby cranks (SB's iirc) OE routeing for much better very high RPM operation. live every 24 hour block of time like it's your last day on earth

Re: SMALL BLOCK FIRING ORDER SWAP [Re: Cab_Burge] #2665733 06/14/19 08:38 AM 06/14/19 08:38 AM
Joined: Nov 2006 Posts: 370 Queensland Australia M moparmacka OP enthusiast
moparmacka OP enthusiast M Joined: Nov 2006 Posts: 370 Queensland Australia	My head hurts......

Re: SMALL BLOCK FIRING ORDER SWAP [Re: fast68plymouth] #2665734 06/14/19 08:40 AM 06/14/19 08:40 AM
Joined: Nov 2006 Posts: 370 Queensland Australia M moparmacka OP enthusiast
moparmacka OP enthusiast M Joined: Nov 2006 Posts: 370 Queensland Australia	Thanks mate. I will take that on board.

Re: SMALL BLOCK FIRING ORDER SWAP [Re: Cab_Burge] #2665789 06/14/19 11:45 AM 06/14/19 11:45 AM
Joined: Sep 2014 Posts: 4,457 Washington M madscientist master
madscientist master M Joined: Sep 2014 Posts: 4,457 Washington	Originally Posted by Cab_Burge I've spent hours writing down different firing orders based on which two pistons are at TDC at the same time, when you do the 4/7 swap all you have accomplished is to move the problem from the driver side rear block to the front passenger side of the block, correct 1843 6572 Standard Mopar V8 and early Chevy V8 firing order. The 7-4 swap =1873 6542 if you change it to: 1543 6872 you then change the two cylinders firing in line from each other to the passenger side two rear cylinders, correct I'm done for tonight on this but a custom built crankshaft could remedy the issues, correct It's not so much that you are moving 5 and 7 from firing next to each other. It's better to have 2 and 4 fire next to each other, as the cooling of the front cylinders is better. Again, that is about the least of why it's done. Changing the FO moves the firing pulses and the engine should be noticeably smoother. The 4 cylinder swap firing order AFAIK came on early Cadillacs and they are butter smooth. IIRC there are 8 possible firing orders for a V8. The 4 cylinder swap is the best but it's damn hard to get cam cores for a Chrysler with that swap. Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston

Re: SMALL BLOCK FIRING ORDER SWAP [Re: moparmacka] #2665884 06/14/19 04:06 PM 06/14/19 04:06 PM
Joined: Oct 2006 Posts: 246 Cranberry Twp PA (North of Pit... rumblefish72 enthusiast
rumblefish72 enthusiast Joined: Oct 2006 Posts: 246 Cranberry Twp PA (North of Pit...	There's some very timely information that just came out related to this ... go to https://www.enginelabs.com/engine-t...jamora-answers-your-tech-questions-pt-1/ and read question #6 1972 Pro-Street 'Cuda, 500" Eagle stoker B Block, Eddy RPM heads, Victor Manifold, 850 Mighty Demon, Hemi 4 Speed, Dana 60 w/4.88 gears - Built by Hansen Racing Middlesex - NJ

Re: SMALL BLOCK FIRING ORDER SWAP [Re: rumblefish72] #2665961 06/14/19 07:48 PM 06/14/19 07:48 PM
Joined: Jan 2005 Posts: 4,243 Charlotte, North Carolina sgcuda master
sgcuda master Joined: Jan 2005 Posts: 4,243 Charlotte, North Carolina	Excellent article on 4/7 swaps. Also, great info on the EZ roller lifters.

Re: SMALL BLOCK FIRING ORDER SWAP [Re: sgcuda] #2666053 06/15/19 12:00 AM 06/15/19 12:00 AM
Joined: Oct 2006 Posts: 246 Cranberry Twp PA (North of Pit... rumblefish72 enthusiast
rumblefish72 enthusiast Joined: Oct 2006 Posts: 246 Cranberry Twp PA (North of Pit...	The next article on wideband O2 sensors and high overlap cams was very interesting. I had heard about how self-learning ECUs could think idle was lean due to lots of unburnt oxygen and add fuel when the extra oxygen actually was coming from the overlap. And in another article, they showed what the computer would due if you had a bad spark plug wire (it added fuel). EFI is neat but you have to understand what the sensors are telling you and how the system is reacting!! 1972 Pro-Street 'Cuda, 500" Eagle stoker B Block, Eddy RPM heads, Victor Manifold, 850 Mighty Demon, Hemi 4 Speed, Dana 60 w/4.88 gears - Built by Hansen Racing Middlesex - NJ

Page 2 of 2

1

2

Moderated by Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer

Hop To

Powered by UBB.threads™ PHP Forum Software 7.7.1