Moparts
Small Block pump gas bracket engine
Posted By: Dunnuck Racing
Small Block pump gas bracket engine - 11/27/14 11:38 PM
Thought I would share some of my personal bracket engine I'm finishing up.
I used a BPE rotating assembly in my old block, .040 over 360 block. 4.125 stroke for 423" small Block.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/27/14 11:50 PM
I took the previously ported RPM heads out as far as possible for some more port volume and flow.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/27/14 11:55 PM
Along with the Super Victor intake manifold
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 12:01 AM
Final compression came out to 11.58 to 1. I am using a custom solid flat tappet camshaft.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 12:06 AM
First pull after seating the rings, I used my old 1 3/4" headers and modified 950 carburetor.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 12:11 AM
On the first pull my old reliable MP distributor started to come apart. So the power fell off fast due to timing retarding. After changing the distributor out and a little tuning we had,.....
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 12:22 AM
After switching to 1 7/8" headers and a stockish1050 Dominator New bests.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 12:27 AM
Started dialing in the fuel curve but some of my jets I needed were missing so I stopped at this,point .
A little tuning should get the top end a little better than the best pull so far
I'm thinking it's not too bad for a pump premium small block with Edelbrock heads and a flat tappet cam
Keith
Posted By: Cab_Burge
Re: Small Block pump gas bracket engine - 11/28/14 02:05 AM
Those are oustanding results for the parts used, especially on pump gas
Posted By: RV2
Re: Small Block pump gas bracket engine - 11/28/14 02:15 AM
Wow!
Posted By: 71Pan
Re: Small Block pump gas bracket engine - 11/28/14 02:41 AM
Awesome what are the cam specs. Did you girdle the bottom end?
Posted By: gregsdart
Re: Small Block pump gas bracket engine - 11/28/14 03:39 AM
Lets see, light weight motor (sb vs bb) fast, and cheap! Pretty hard to beat that combo
Most only get two out of the three!
Posted By: J_BODY
Re: Small Block pump gas bracket engine - 11/28/14 04:21 AM
Neat build Keith! Thanks for sharing
Posted By: DblOJoe
Re: Small Block pump gas bracket engine - 11/28/14 04:32 AM
Nice Kieth
Now you have the long wait till spring.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/28/14 05:20 AM
Thanks for the kind words everyone! The cam is a custom grind I did. It is 270/ 276 @ .050. The lift is just under .650 after lash.
Keith
Posted By: ScottSmith_Harms
Re: Small Block pump gas bracket engine - 11/28/14 06:04 AM
Nice build! What rocker arms are you running (and ratio, etc.)?
Posted By: B3422W5
Re: Small Block pump gas bracket engine - 11/28/14 06:24 AM
Great numbers
That should easily get a 3200-3300 pound car in the 9's with no sweat.
Posted By: mopar dave
Re: Small Block pump gas bracket engine - 11/28/14 06:38 AM
nice combo and great numbers. my 408 cant seem to get there with similar compression and better flowing indy heads. those edelbrocks are working very well.
Posted By: Crizila
Re: Small Block pump gas bracket engine - 11/28/14 06:56 AM
Quote:
Those are oustanding results for the parts used, especially on pump gas
Exactly what octane pump gas are you using and what total lead are you running - and what AF ratio are you shooting for?
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/29/14 02:52 AM
I am running the local 93 octane premium which states 10% ethanol. When I test it, it shows 6% ethanol content.
Previous testing with this fuel has shown it normally makes best power around 12.2 to 1 a/f ratio. This thing is showing 12.8 to 1 on the O2 meter right now on the top of the pull.
Plug readings and testing so far confirmed that it needs more fuel.
Best power so far has been with 33 degrees total timing.
I also have available around here some non ethanol 93 that usually makes more power and likes a slightly leaner mixture.
Keith
Posted By: ScottSmith_Harms
Re: Small Block pump gas bracket engine - 11/29/14 05:13 AM
Quote:
Nice build! What rocker arms are you running (and ratio, etc.)?
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/29/14 05:30 AM
Oops!
Missed your post before. It has 1.6 Crane Gold rockers to get the lift I showed.
Posted By: ScottSmith_Harms
Re: Small Block pump gas bracket engine - 11/29/14 05:34 AM
Thank you, any issues with those rockers? I've heard mixed reviews on the Cranes
Posted By: pittsburghracer
Re: Small Block pump gas bracket engine - 11/29/14 05:38 AM
Sounds like a nice build. What will this be going in as I would like to follow this one. Matt and I are both upping the HP in our small-blocks for next year.
Posted By: Ian
Re: Small Block pump gas bracket engine - 11/29/14 06:10 AM
Keith ,very nice build mate and thanks for sharing it with us,not many do that anymore ,you will have people that will say thats high hp but its what works and i for one are backing you
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/29/14 06:36 AM
This is going in my 70 Challenger. It weighed 3070 last time I weighed it with me in it. Weight might be a little more as I'm going back to my steel hood next spring.
May look at pulling some weight in other ways if I have time, but after sitting out last summer being crew chef only for my wife's car, I need mine back.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/29/14 06:42 AM
Ian, thanks and I know you build some pretty mean small blocks on your side of the pond also!!
As far as Crane rockers go, I have used a few sets on builds over the years with no issues other than one set that had bad adjusters. I have used Hughes rockers recently and like those too.
I'm not a big believer in roller bearings in a stock sized shaft rocker.
I have a set of Crane Golds in my wife's 440 that have been beat on in for at least 15 years. The wear area is still like New on the rocker/ shaft area.
Keith
Posted By: mopar dave
Re: Small Block pump gas bracket engine - 11/29/14 06:47 AM
do you generally favor the 4.125 stroke over the 4.000?
Posted By: 1967dartgt
Re: Small Block pump gas bracket engine - 11/29/14 06:55 AM
Wow that is a nice build.
Posted By: 340RICK
Re: Small Block pump gas bracket engine - 11/30/14 03:18 AM
Thanks for sharing your build. That's one mean small block
Posted By: fishy340
Re: Small Block pump gas bracket engine - 11/30/14 03:37 AM
Very nice and should kick..s,Did you fill the block ?
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/30/14 03:56 AM
Thanks again guys, and yes the block has a tall fill.
Posted By: justinp61
Re: Small Block pump gas bracket engine - 11/30/14 04:07 AM
Keith, what cc are the chambers on your heads? I see you have flat tops. I'm going to freshen my 408 this winter and am planning on bumping my compression from 10.9 to 11.4 or 5. My heads are milled to 55cc's and my pistons have either 20 or 22cc dish. So I'm planning dropping the dish to 15 or 16cc's to get the compression up. I'll keep the cam, a Hughes flat solid 260/264 @ .050, .628/.633 lift with 1.6 rockers. Nice build BTW.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 11/30/14 04:19 AM
With the 4.125 stroke and a flat top at zero deck, compression is a little higher than I would want for pump gas using an RPM heads normal chambers.
I took mine out from 63.5 to 68 cc.
It worked out well with the way I wanted to shape the chambers.
And Dave, I like the 4.125 stroke over the 4.00 inch mainly for the lighter putting. The extra stroke causes no issues with skirt and bore wear if its built correctly.
And the torque can be pretty nice!
Keith
Posted By: Crizila
Re: Small Block pump gas bracket engine - 11/30/14 05:07 AM
Quote:
With the 4.125 stroke and a flat top at zero deck, compression is a little higher than I would want for pump gas using an RPM heads normal chambers.
I took mine out from 63.5 to 68 cc.
It worked out well with the way I wanted to shape the chambers.
And Dave, I like the 4.125 stroke over the 4.00 inch mainly for the lighter putting. The extra stroke causes no issues with skirt and bore wear if its built correctly.
And the torque can be pretty nice!
Keith
Yes, I would guess you are pushing the envelope with pump gas. I run the same heads as you except Edelbrock magnums - Hughes ported with almost identical flow #'s - per Hughes. Been running Hughes 1.6 rockers going on 5 years now with no problems.
Posted By: swifter
Re: Small Block pump gas bracket engine - 11/30/14 07:05 AM
Ahhhh know i see why i couldn't bring my motor down to you, you've been playing with your own stuff -lol -steve
Posted By: swifter
Re: Small Block pump gas bracket engine - 11/30/14 07:09 AM
Crew chief? ????? I think i saw "PIT [Edited by Moparts - Family Friendly Site - Keep it clean]" on your shirt one or two times this summer---LOL-Steve
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 12/02/14 04:13 AM
I finished dialing in the pump gas small block today. Here is a comparison of my new build versus the engine that was in my car before.
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 12/02/14 04:24 AM
Torque comparison
Posted By: Dunnuck Racing
Re: Small Block pump gas bracket engine - 12/02/14 04:34 AM
Comparison graph,
Ought to get my fat butt down the track a little faster,....
Keith
Posted By: FlyFish
Re: Small Block pump gas bracket engine - 12/02/14 02:53 PM
VERY NICE!!
Posted By: Crizila
Re: Small Block pump gas bracket engine - 12/02/14 04:05 PM
Quote:
Torque comparison
Wow! Minimal low end give-away. Awesome #"s without resorting to "exotic" parts. I have heard that 600HP is the magic # not to exceed for a stock small block? I have 3 E58 motors ( all are 1979 vintage ). I have sonic tested 2 of them and the wall thickness was very good on both blocks ( around .2 ). Is this indicative of the E58 motor or am I just lucky?
Posted By: Rob C
Re: Small Block pump gas bracket engine - 12/03/14 05:29 AM
You can do more power than 600 on stock blocks BUt the machine work has to be the top of the cream perfect.
Check FABO on a thread addressing that very issue and see how many are routinely exceeding that power level and making use of it regularly.
Posted By: Wedgeman
Re: Small Block pump gas bracket engine - 12/04/14 04:55 AM
Mine is a 408ci with 606 hp on the dyno
best 60ft is 1.30 sec and 6.40 1/8 mile...
I had fun all summer with no problems.....except for 1 Indy rocker arm in the very last pass of the season!!
'67 Barracuda 3000lbs