Desktop Dyno? and some other Q's - The 1947 - Present Chevrolet & GMC Truck Message Board Network

cor86 · 07-26-2010, 12:45 PM

My motor is about done, but I need a little help. First off, we will start from the beginning. I picked up a Mark IV 454 with a bunch of goodies for $400. It isn't anything real special, but came with a set of 063 semi-closed chamber oval port heads, Eddy DP Performer intake, Eddy 1411 750 cfm carb, fairly new SFI flexplate, fairly new NAPA starter and oil pan, and Hooker headers (was in a 88 'Burb). Upon disassembly, I found two spun rod bearings, so it went to the machine shop. The good news? It looks like it didn't rack up too many miles since its last rebuild. Cylinders just needed a light honing, but crank was already 10/10 and trash. So...very little spent machining. The heads did need hardened ex. seats, but that was it (stayed with stock valve size). I then picked up a TH400 (long tail) for $100 (even came with dust sheild, converter, and fill tube!) and a 5 lug 14 bolt, with driveshaft, for another $100. I should be picking the motor up from the shop next week, and hopefully get it all put together soon after. (with pics!) I have a few questions before I finish ordering parts. First, can someone tell me how much power this will be putting out, and CR? (desktop Dyno) Second, which TC should I run, TCI Sat. night sp or ??? (around 2,000) Finally, is the 14b overkill, will my stock 10b live? It is a more MPG friendly 3.08 versus the 14b's 3.73. Both will need a LSD, since the 10 is open and the 14 has a Gov-bomb. I appreciate any feedback and thanks for taking the half hour to read this. Final specs on motor below

Comp Cams XE 268H-10 (11-242-3) 224-230@050 268-280advertised .515/.520 with 110 lobe sep.
Cast flat tops with stock 063 heads
Same carb and intake as above

cor86 · 07-27-2010, 07:07 PM

CR looks to be around 9:1. Found a neat calculator that I thought I would share. The link is below. Oh yeah, I found a build (Corvettefever.com) using the same cam and a slightly lower CR (8.6). They were running rect. port iron heads, so not a perfect match, but it made 483 hp @5,300 and 541 lb-ft @3,900!

If I end up with anything near that, I will be perfectly content, especially since I will have less than $2,000 in the whole swap!

I would still like some input on the TC and rear end dilemma, and an actual Desktop Dyno calculation, if anyone cares to chime in.

CR calculator: http://www.rbracing-rsr.com/compstaticcalc.html

07-26-2010, 12:45 PM	#1
cor86 Registered User Join Date: Mar 2009 Location: Warsaw, IN Posts: 93	Desktop Dyno? and some other Q's My motor is about done, but I need a little help. First off, we will start from the beginning. I picked up a Mark IV 454 with a bunch of goodies for $400. It isn't anything real special, but came with a set of 063 semi-closed chamber oval port heads, Eddy DP Performer intake, Eddy 1411 750 cfm carb, fairly new SFI flexplate, fairly new NAPA starter and oil pan, and Hooker headers (was in a 88 'Burb). Upon disassembly, I found two spun rod bearings, so it went to the machine shop. The good news? It looks like it didn't rack up too many miles since its last rebuild. Cylinders just needed a light honing, but crank was already 10/10 and trash. So...very little spent machining. The heads did need hardened ex. seats, but that was it (stayed with stock valve size). I then picked up a TH400 (long tail) for $100 (even came with dust sheild, converter, and fill tube!) and a 5 lug 14 bolt, with driveshaft, for another $100. I should be picking the motor up from the shop next week, and hopefully get it all put together soon after. (with pics!) I have a few questions before I finish ordering parts. First, can someone tell me how much power this will be putting out, and CR? (desktop Dyno) Second, which TC should I run, TCI Sat. night sp or ??? (around 2,000) Finally, is the 14b overkill, will my stock 10b live? It is a more MPG friendly 3.08 versus the 14b's 3.73. Both will need a LSD, since the 10 is open and the 14 has a Gov-bomb. I appreciate any feedback and thanks for taking the half hour to read this. Final specs on motor below Comp Cams XE 268H-10 (11-242-3) 224-230@050 268-280advertised .515/.520 with 110 lobe sep. Cast flat tops with stock 063 heads Same carb and intake as above

07-27-2010, 07:07 PM	#2
cor86 Registered User Join Date: Mar 2009 Location: Warsaw, IN Posts: 93	Re: Desktop Dyno? and some other Q's CR looks to be around 9:1. Found a neat calculator that I thought I would share. The link is below. Oh yeah, I found a build (Corvettefever.com) using the same cam and a slightly lower CR (8.6). They were running rect. port iron heads, so not a perfect match, but it made 483 hp @5,300 and 541 lb-ft @3,900! If I end up with anything near that, I will be perfectly content, especially since I will have less than $2,000 in the whole swap! I would still like some input on the TC and rear end dilemma, and an actual Desktop Dyno calculation, if anyone cares to chime in. CR calculator: http://www.rbracing-rsr.com/compstaticcalc.html



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