Results 1 to 15 of 41

Thread: 400FWHP TBI build attempt thread

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,327
    Quote Originally Posted by Gojira94 View Post
    That will be one fun van... is your block decked? The best I could come up with on my old block or another offering where I got my SB, both with -12.3cc dish, was a hair over 9:1 with the 7733SH-1 shims or almost 8.9:1 with the .028GM 4.1 bore gasket. That would have been very 87 friendly but would have given me a quench of over .070 with pistons .025 in the hole. IMHO reman short blocks should be decked and finished to .012 - .015 in the hole for flexibility either way and put quench range between .035 - .050 max. My quench will be a little looser than I'd find ideal but should be ok at .051. Most GM crate engines have quench looser than that with no detonation issues on 87.

    Your cam has me intrigued. What's the IVC ABDC? Wondering what kind of DCR that cam gives and what dynamic cranking pressure would be. I calculated my DCP at 162.22PSI. Good thing to know when doing a compression test down the road some day.
    Block is a stock deck, 2005ish GM 1-ton Vortec 350 crate engine. Hecho en Mexico. Where are you calculating your quench from? The top of the piston recess? My pistons are 0.025" down. The GM ZZ4 and 330 HP 350 HO ran 0.051" compressed head gaskets when they were built. The ZZ4 had flat tops and L98 aluminum heads and the 330 hp 12cc dished with Vortecs. I feel the slight compression difference advertised between the factory Vortec engine and the 330 HP crate is due to the head gasket.

  2. #2
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,327
    Running the numbers in my setup has an IVCL of 33.5° ABDC @ 0.050 and 61° ABDC @ 0.006. Static compression calculates out at 9.41:1 and Dynamic is 8.36 as calculated by Silvolites calculator. Heads are right at 62cc even though they are 64cc advertised, guess it has to do with the valve choice. I am cranking 180 psi at 700 ft elevation. Overlap is 57°.

  3. #3
    Fuel Injected!
    Join Date
    Mar 2015
    Posts
    84
    Quote Originally Posted by Fast355 View Post
    Block is a stock deck, 2005ish GM 1-ton Vortec 350 crate engine. Hecho en Mexico. Where are you calculating your quench from? The top of the piston recess? My pistons are 0.025" down. The GM ZZ4 and 330 HP 350 HO ran 0.051" compressed head gaskets when they were built. The ZZ4 had flat tops and L98 aluminum heads and the 330 hp 12cc dished with Vortecs. I feel the slight compression difference advertised between the factory Vortec engine and the 330 HP crate is due to the head gasket.
    I'm using the rudimentary method for calculating quench. Volume of cylinder from top of piston to deck height (.025) + compressed gasket thickness (.026) = .051"

    My SCR I used the calculator at CSG's site (http://www.csgnetwork.com/compcalc.html) and DCR with the calculator at Wallace Racing's site (http://www.wallaceracing.com/dynamic-cr.php). I'm calculating at 340' altitude for mine, just above the sandhills region of NC. I asked about intake valve closing after BDC to get a ballpark of how much DCR you'd be running. You have more than I thought you might. A lot of folks I've heard say above 7.8-8.0 you'll want to run gas with an octane rating higher than 87 vs. detonation. Being that almost all 87 octane fuels have 10% ethanol it actually pads that ever so slightly. How much would be pure speculation. But I'm accounting for the difference in stoich for ethanol blended fuels in my EBL/TunerPro stuff.

  4. #4
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,327
    Quote Originally Posted by Gojira94 View Post
    I'm using the rudimentary method for calculating quench. Volume of cylinder from top of piston to deck height (.025) + compressed gasket thickness (.026) = .051"

    My SCR I used the calculator at CSG's site (http://www.csgnetwork.com/compcalc.html) and DCR with the calculator at Wallace Racing's site (http://www.wallaceracing.com/dynamic-cr.php). I'm calculating at 340' altitude for mine, just above the sandhills region of NC. I asked about intake valve closing after BDC to get a ballpark of how much DCR you'd be running. You have more than I thought you might. A lot of folks I've heard say above 7.8-8.0 you'll want to run gas with an octane rating higher than 87 vs. detonation. Being that almost all 87 octane fuels have 10% ethanol it actually pads that ever so slightly. How much would be pure speculation. But I'm accounting for the difference in stoich for ethanol blended fuels in my EBL/TunerPro stuff.
    I have never run this engine on 87. Even STOCK on the stock tuning it had knock retard on 87 octane. The GM 395 Marine cam made it worse at 9.6 static. It was about 8.4:1 dynamic. I have had this engine drinking E85 with a flex fuel operating system for some time. With the old setup it had to have a very conservative timing map on 93. After E85 I was able to give it a healthy timing bump and gained power everywhere. With this setup I will be happy if I can run a good timing advance curve on 93. I also have a cooling system that never runs more than about 190°F on the hotest day.
    Last edited by Fast355; 05-24-2018 at 04:58 AM.

  5. #5
    Fuel Injected!
    Join Date
    Mar 2015
    Posts
    84
    It's been a little slow getting through the new short block. Every fastener and component being re-used has to be cleaned and some of it painted. Right now I've got the bottom end buttoned up, cam installed, timing set and cover on. First I painted the block (boring black) I repainted the oil pan, timing cover and will be painting the brackets on the manifold (also boring black). Water pump is almost new and fine. I still have some Old Ford Blue, thought that would look decent on an expendable part like the water pump. The aluminum accessory brackets need a good cleaning before they go back on.

    The short block was advertised as being stock deck height/ .025 in the hole but eyeball evidence suggests otherwise. The china walls are still smooth but the pistons look a lot closer than .025 to the deck. Also, there are telltale machining marks on the deck. I went to some degree of trouble to acquire the Mahle 5746 .026" Nitroseal gaskets and I may not be able to use them. In some ways it may be a good thing, I may be able to shave a little off the compression ratio and tighten the quench at the same time. Anyway, here's a few pics. First one is the old short block (10054727 casting with 14088535 cast crank). Others are the new one.
    Attached Images Attached Images

  6. #6
    Fuel Injected!
    Join Date
    Mar 2015
    Posts
    84
    This block has definitely been decked. Pistons in the hole:
    1 .013
    3 .015
    5 .017
    7 .017
    2 .012
    4 .014
    6 .015
    8 .017

    I'd just call it a .015" deck height block. .008"-.013" below factory .025" deck height. With the Mahle 5746 gasket quench would go from .051" to between .038"-.043" which would be closer to ideal. Static CR would bump slightly and I'll have to go back to the calculators on that but I think SCR would be around 10.2:1. If this short block was the other offering with -12.3cc dish pistons I'd be shitting in high cotton on CR vs 87 pump gas in the mid-9s. I'll play around with the head gasket numbers in the .033"-.035" range and see if I find a happier medium. But if I'm above 8.1:1 DCR/ 9.7:1 SCR I don't think I'll be looking much different.
    Attached Images Attached Images
    Last edited by Gojira94; 06-07-2018 at 07:50 AM.

  7. #7
    Fuel Injected!
    Join Date
    Mar 2015
    Posts
    84
    I carefully taped off the RMB seal housing and painted the back of the block, got the water jackets and all bolt holes on the deck cleaned out of the crate oil/ preservative and got the heads on. One word about the heads- for a $900 pair of heads I figured there might be one or two issues that come up. The holes for the dowels on the deck were slightly off or too small. They may have missed the finish work on those. Both sides I had to ever so gently open the holes up with a 5/16" drill bit, but after that they settled right down. My other concerns will be with the pushrod clearance and alignment to the casting. I can handle both. These heads have gotten high praise from Skip White and veteran porter Tony Sizemore at HeadBytes. Say what you will about Tony, but he did a video series of the 200cc head where ProMaxx gave him bare castings to cut up and analyze when AFR, TrickFlow, etc wouldn't do it.

    I still have a number of things on the list to get it finished and buttoned up, including but far from limited to:
    Finish cleaning and painting external parts like pulley, engine mount brackets, water pump, topside brackets
    Clean front accessory brackets
    Prep and install lifters, retainers & spider
    Install intake, 180* thermostat, water neck
    Figure out brake booster plumbing fitting size
    Figure out heater to intake hose plumbing
    Flush Radiator
    Flush heater core
    Clean oil cooler lines/ fittings
    Install oil cooler block to engine block
    Clean PS pump and double check for leaks

    But anyway, here's some pics. Today I'll be digging out the tuning work I started in January 2017 and start getting feedback and help with that. Again, this is going to be EBL Flash driven with VRFPR. Wish I had a week off from work to just dive in and get it all done uninterrupted. :)
    Attached Images Attached Images

  8. #8
    Fuel Injected!
    Join Date
    Mar 2015
    Posts
    84
    Rather old first attempt at building and smoothing a VE table, based on... gut I guess. No idea if I'm even close but this is what I started with, dreaming back in Dec. 2016. screen shots of both graphs as well. For spark tables I considered working with Vortec head stock tables as a fairly conservative ballpark, maybe even stock aluminum head LTI F body tables and dialing it back pretty broadly since classic Gen I SBC isn't reverse cooled. No chance of making 46* anywhere like an LT1, especially at 10.2:1 lol. This is where I really have no idea to build a spark table. I still think the Vortec tables are decent place to start, maybe something like an aluminum headed L98 as a base? The ProMaxx 2169 heads' flow numbers are well published, they post them on their site, Skip White measured them a year ago, I think HotRod magazine online had a budget head shootout with flow numbers when they were still Patriot heads, though I'm pretty sure that was a previous design.
    Attached Images Attached Images
    Attached Files Attached Files

Similar Threads

  1. First TBI conversion attempt on a FORD !
    By bronco tom in forum Introductions
    Replies: 5
    Last Post: 01-27-2017, 11:22 PM
  2. First TBI conversion attempt on a FORD !
    By bronco tom in forum Introductions
    Replies: 0
    Last Post: 11-02-2016, 05:32 AM
  3. Hacking attempt.
    By historystamp in forum GearHead EFI Forum Support
    Replies: 12
    Last Post: 05-06-2015, 11:55 PM
  4. Replies: 10
    Last Post: 02-11-2014, 06:42 AM
  5. The LS1 411 PCM thread
    By EagleMark in forum GM EFI Systems
    Replies: 6
    Last Post: 05-20-2011, 03:09 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •