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-   -   Help with BB combo (https://67-72chevytrucks.com/vboard/showthread.php?t=317313)

Ont67shortbox 12-02-2008 04:08 PM

Help with BB combo
 
Hi I am currently building an engine for my 67 need to know if my combo will be good or needs tweaking in any areas. 454 .030 over,forged pistons .250 dome,*241* cast heads approx 113 cr/ 2.25/1.88 Ferrera valves,port matched,mild bowl work,CC 924 springs,1.7 Crane roller rockers,Comp 11-678-5 cam kit ,244/252 @.050,.590/.598 lift (solid)Weiand Team G or PP Hurricane intake with 800 cfm Holley, Hooker Super comp (2in) headers, Turbo 350 rebuilt with Neil Chance 3500 stall convertor,12 bolt posi with 3.73 gears, 31x13x15 tire,67 short wheel base,16 gal cell behind rear,battery relocated ,buddy buckets changed to race seats,coil springs with trailing arms , drop shocks,lowered 41/2 inches front 6 inches rear Is there anything I need to reconsider? This will be a 75% strip/ 25% street truck ,What ET/MPH can I expect?any help or ideas would be greatly appreciated, Thanks

ripdog28 12-02-2008 04:36 PM

Re: Help with BB combo
 
The cam and intake look good for the strip but your heads are holding you back. Unless you do some major port work you may want to get some other ones. Even some aftermarket Irons will out flow them by a ton. the cost in stock ones with new springs, valves, port work puts you just shy of some Dart/summit/World or even Patriot Aluminum ones. all of which are better off then stockers. Super Chevy mag just did a build using Patriot which are considered crap in some groups. 496BBC with a cam about the same gave 597HP598TQ.

d10s69c10 12-02-2008 04:45 PM

Re: Help with BB combo
 
Quote:

Originally Posted by ripdog28 (Post 3004581)
even Patriot Aluminum ones. all of which are better off then stockers. Super Chevy mag just did a build using Patriot which are considered crap in some groups. 496BBC with a cam about the same gave 597HP598TQ.

i agree with patriot not being great. but miles over stock.. your heads will be your largest "power inhibitor"

ripdog you got a dyno curve availible for that 496? seems to be very close to my overall goal.

Ont67shortbox 12-02-2008 05:58 PM

Re: Help with BB combo
 
the heads are already done,new valves,bowl work,port matched,bronze guides,springs,retainers keepers,they flow as good or better than the oval Merlins,Alum heads here are $3000,I have $1400 in these, and if need be I could use spray ,but would like to be N/A

d10s69c10 12-02-2008 06:02 PM

Re: Help with BB combo
 
in that case then i say get to it put that thing together and give us some pictures to gawk at.

got any thoughts on a beefier driveshaft?

i just Twisted mine and my 12 bolt the other day.. im going with a custom shaft and a 9 inch now. just .02

Ont67shortbox 12-02-2008 06:15 PM

Re: Help with BB combo
 
2 Attachment(s)
I was looking at a 9 inch from DTS, they make a bolt in housing for our trucks,drive shaft will have 1350 joints and moly or aluminum,not sure yet,here is a pic before it was dropped...

ripdog28 12-02-2008 10:08 PM

Re: Help with BB combo
 
Ont67: you can get new Dart Iron Eagle 308cc new for $1400 and they will outflow stocks ported and all. If you can sell your stockers, recover what you can and get some. David Vizzard has done a bunch of builds with them and he preaches by them. He even stated that when porting the Darts he lost some midrange power.

d10s69c10: I have the graph at work but i do remember the cam was around 240dur 590lift with Hyd rollers so very streetable. the tq curve started at 3500rpm and was about 480ft/lb:lol: to much for the low end dyno to take. and about 598ft/lb at 4800rpms. HP was 400@3-3500(not sure) and 596-7@5800

djracer 12-03-2008 08:30 AM

Re: Help with BB combo
 
Quote:

Originally Posted by Ont67shortbox (Post 3004737)
I was looking at a 9 inch from DTS, they make a bolt in housing for our trucks,drive shaft will have 1350 joints and moly or aluminum,not sure yet,here is a pic before it was dropped...


Sweet truck! I love the big tire tucked under there with the rallies. Get that fat motor together and be ready to play when mother nature permits.

drag_72 12-03-2008 10:55 AM

Re: Help with BB combo
 
yah weather down here is goin to be very permiting lol for a while! anyone have any idea wat he will be runnin? cuz i have almost the same setup?

drag_72 12-03-2008 10:58 AM

Re: Help with BB combo
 
im not tryin to say ur wrong ripdog but i think his heads will do fine... we have built many bbc using stock heads but doing work to them and they flow just as good just somthin to think bout ont67 before you go spendin money u dont need to lol

ripdog28 12-03-2008 11:17 AM

Re: Help with BB combo
 
Not saying that Stock heads wont do fine. What i am saying is that for the money and his cam they will be holding him back. Cams are cheap to replace but people usually get a cam that dont match there heads. When in actuality you Must have them match.

drag_72 12-03-2008 11:19 AM

Re: Help with BB combo
 
yes very true! touche

70rs/ss 12-03-2008 04:06 PM

Re: Help with BB combo
 
Remember he is in Canada so what we can pick up from summit for $1500 may cost double that to him (duty and whatnot once it gets to the border). On the other hand, those $1400 ported iron heads are brand new and way easier to sell than a "slightly used" set, so if you are iffy at all sell them new you'll do better. I used a set of Vortec iron heads on my last 468 and they worked excellent, I'll use them again since I have two more sets, but if you have aspirations high high rpm on that motor (again with that cam you better) the stockers will be the restriction in your motor. I recieved and shipped a set of heads to a member in Canada and saved him about $800, so if you want to ship those new Darts to me I'll drop em at the post office and send them to you (USPS doesn't get stopped for duty into Canada?) LMK

Ont67shortbox 12-03-2008 04:23 PM

Re: Help with BB combo
 
Thanks for the offer,I really appreciate it,I am going to try the heads,my cam works from 24-6800, I got the intake today,short block is at the machine shop,on a tight budget,still off work for a year after kidney transplant,truck has been in the garage for 4 years while I was sick,and thats why I am hoping for hp/et predictions, I am outta touch lol, thanks again for the offer

d10s69c10 12-03-2008 05:22 PM

Re: Help with BB combo
 
Quote:

Originally Posted by Ont67shortbox (Post 3006517)
I am hoping for hp/et predictions, I am outta touch lol, thanks again for the offer

I think its easy to predict at the minimum 450/450. but depending on all the little details it could get 600/650. until you get a good ET time without a dyno I cant even think to predict what your 1/8-1/4 mile times.

basicly from here i could throw a rock in the dark and tell you it somewhere between 40-200 feet away.....wow I'm no help.:uhmk:

wow sorry about your kids man i know from family experience that is no easy recovery. haert goes out to you.

djracer 12-03-2008 07:39 PM

Re: Help with BB combo
 
I will throw a guess out there I'll say low 11's!

drag_72 12-04-2008 12:17 PM

Re: Help with BB combo
 
low 11's with 125 shot?

Super73 12-04-2008 12:54 PM

Re: Help with BB combo
 
Quote:

Originally Posted by Ont67shortbox (Post 3006517)
I am going to try the heads,my cam works from 24-6800,

I think what a lot of these guys are trying to tell you is that this cam may not actually work up to 6,800 do to the head flow. Do you have any flow bench numbers? I'd be happy to put the engine set up in performance trends engine analyzer and give it a run..

Ont67shortbox 12-04-2008 04:30 PM

Re: Help with BB combo
 
Not positive about the increases but at .600 lift (my cam is 590/598) they flowed 294/193,thats why I chose that cam,and if you could run that that would be great,thanks for the help, Brian

ripdog28 12-04-2008 05:37 PM

Re: Help with BB combo
 
glad you have flow #s. Like we said they will work. but BBC heads should flow about 330/225+ @.600lift(that is with small runners). With your flow #s and some aftermarket iron i would guess a 40+/-HP diffrence.

69trk 12-04-2008 05:52 PM

Re: Help with BB combo
 
How accurate is the engine analyzer? Id like to try it and compare it with my dyno sheets.

d10s69c10 12-04-2008 07:40 PM

Re: Help with BB combo
 
Quote:

Originally Posted by 69trk (Post 3008634)
How accurate is the engine analyzer? Id like to try it and compare it with my dyno sheets.

analyzer is the key word. its a well educated guess to perfect specs well perfect everything.

they are usually max potential. so they are close but often a bit higher than real life.

Super73 12-04-2008 09:18 PM

Re: Help with BB combo
 
Quote:

Originally Posted by d10s69c10 (Post 3008822)
analyzer is the key word. its a well educated guess to perfect specs well perfect everything.

they are usually max potential. so they are close but often a bit higher than real life.


IMO Desk Top Dyno is much more optimistic then Powertrends Engine Analyzer. For instance Engine analyzer says I should be making the following and right next to it you can see my RWHP numbers going through a 4L80E, 4,900 converter (locked), 12 bolt with 3.73's and 30x14.50 ET street.

RPM - Engine Analyzer - RWHP from dyno Jet - Difference --- %
2850 ----- 130 --------------- 180 ------------ (-49) ---- 72.5%
3200 ----- 169 --------------- 211 ------------ (-42) ---- 80.1%
3550 ----- 228 --------------- 235 ------------- (-6) ---- 97.4%
3900 ----- 275 --------------- 255 -------------- 20 ---- 107.9%
4250 ----- 312 --------------- 282 -------------- 29 ---- 110.3%
4600 ----- 348 --------------- 328 -------------- 20 ---- 106.1%
4950 ----- 392 --------------- 347 -------------- 45 ---- 113.0%
5300 ----- 437 --------------- 381 -------------- 56 ---- 114.6%
5650 ----- 459 --------------- 404 -------------- 55 ---- 113.6%
6000 ----- 476 --------------- 418 -------------- 58 ---- 113.9%
6350 ----- 493 --------------- 424 -------------- 69 ---- 116.2%
6700 ----- 503 --------------- 426 -------------- 77 ---- 118.0%
7050 ----- 494 --------------- 412 -------------- 82 ---- 119.9%
7400 ----- 473 --------------- 387 -------------- 86 ---- 122.2%


The program says I should be making much less TQ/HP than I really am until 3,700rpm or so when it evens out and the program starts showing I am making more. But the program is estimating power at the crank, not at the wheels.

The interesting thing is it does seem to hit the peak HP/TQ RPM fairly consistantly. I would be very interested in runing a couple combos through Engine analyzer and comparing what others have seen on an engine dyno. I started a thread for Engine analyzer and Drag analyzer, so please feel free to drop your combos in there and I'll be happy to run them through.

drag_72 12-05-2008 10:29 AM

Re: Help with BB combo
 
so no one has answered my question... lol wat do u think that setup w. 125 plate shot would run?

djracer 12-05-2008 02:22 PM

Re: Help with BB combo
 
We thought that you were saying it would take the 125 shot to run low 11's.

I'd say mid to upper ten's depending on how much of the run was on the bottle.


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