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427 Build And Drag Test
Posted: Mon Jan 11, 2021 11:55 pm
by vortecpro
Recently I built a different kind of build, here it is. A 9.7 compression 427 BBC, I used a Autotec piston with a 1.5 1.5 3.0 ring pack. The heads were 1971 GM 820 castings, used only because I had them, 1.880/2.190 valves, ported. I used the 1966 factory GM Q-Jet cast iron intake with the Q-Jet, and a 1 inch 4 hole spacer was used. I wanted a smooth 780 RPM idle with 19-20 inches of vacuum, I wanted reliability so I chose the GM factory 390 HP 427/396 350 HP hyd cam. I had my cam grinder change the lobe separation from 115 to 112, specs: 216/218/460/480 I installed the cam on a 109.5 Intake centerline. My cam core was an 1960 GM cam core with 1970s TRW hyd lifters. I ran 110/290 spring pressure. I used Comp cams roller tip rockers 1.72 with a 3/8 .080 wall moly pushrod, with adjustable guide plates. A factory GM 4 quart oil pan was used. 10/40 Maxima oil was used. So my plan is to install this 427 in my 68 Chevelle and see how fast I can get it to go. Why I have no idea. Some pictures.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 12:01 am
by vortecpro
Some more pictures.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 12:06 am
by bob460
Nice build
......my guess 11.00 @120mph
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 12:12 am
by vortecpro
Thanks-not sure about that 120 mph though.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 3:04 am
by maxracesoftware
vortecpro wrote: ↑Tue Jan 12, 2021 12:12 am
Thanks-not sure about that 120 mph though.
nice build pictures !
are you going to Dyno test your Engine before you install it in your Chevelle ?
do you "stake" the Cam sprocket at the Cam degree bushing hole ?
or is there a small outer lip edge on the bushing hole preventing possible degree bushing from falling out ?
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 6:29 am
by Monza355
Interesting for sure ! Did you dyno test the engine after the build ?
How’s the car going to be set up. Transmission. Gearing. Converter etc.. ?
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:05 am
by vortecpro
maxracesoftware wrote: ↑Tue Jan 12, 2021 3:04 am
vortecpro wrote: ↑Tue Jan 12, 2021 12:12 am
Thanks-not sure about that 120 mph though.
nice build pictures !
are you going to Dyno test your Engine before you install it in your Chevelle ?
do you "stake" the Cam sprocket at the Cam degree bushing hole ?
or is there a small outer lip edge on the bushing hole preventing possible degree bushing from falling out ?
I ran out of lock plates so I did put a step in the gear. I'am still testing carbs, I have two more to test. I also need to make a adapter so I can mount my air turbine. Heres were I'am at so far.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:08 am
by vortecpro
Monza355 wrote: ↑Tue Jan 12, 2021 6:29 am
Interesting for sure ! Did you dyno test the engine after the build ?
How’s the car going to be set up. Transmission. Gearing. Converter etc.. ?
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:09 am
by vortecpro
vortecpro wrote: ↑Tue Jan 12, 2021 8:08 am
Monza355 wrote: ↑Tue Jan 12, 2021 6:29 am
Interesting for sure ! Did you dyno test the engine after the build ?
How’s the car going to be set up. Transmission. Gearing. Converter etc.. ?
I'am still thinking about that.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:20 am
by motormonkey
Nice. Other than weight, those gm cast highrise intakes weren't that bad compared to some aftermarket intakes. I liked the square carb pattern better tho.
Are you going to run the cast exhaust for the full sleeper effect?
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:24 am
by vortecpro
No, it will have headers, 2 inch Hookers. For those interested observed or uncorrected or "in the room HP" was 361 @ 6388 Elevation, 23.76 baro. Another picture.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:30 am
by My427stang
Clearly working well to make that power with a "baby" cam. I may have missed it, but where did you end up for .006 overlap and resulting idle vacuum?
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:37 am
by vortecpro
motormonkey wrote: ↑Tue Jan 12, 2021 8:20 am
Nice. Other than weight, those gm cast highrise intakes weren't that bad compared to some aftermarket intakes. I liked the square carb pattern better tho.
Are you going to run the cast exhaust for the full sleeper effect?
Yes its heavy........this build was about using parts I had lying around that ordinarily would have never been used, I like projects, now I have this complete engine and I kinda like it! Thats how the 327 shop truck was built as well.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:40 am
by vortecpro
My427stang wrote: ↑Tue Jan 12, 2021 8:30 am
Clearly working well to make that power with a "baby" cam. I may have missed it, but where did you end up for .006 overlap and resulting idle vacuum?
The idle vacuum @ 780 RPM was 14.8 inches @ 6388 feet elevation, I think it will go 19-20 down low. Dead smooth idle @ 780 RPM.
Re: 427 Build And Drag Test
Posted: Tue Jan 12, 2021 8:43 am
by tenxal
Have you ever run a QJet with your air bonnet on?
The 2006 date on the dyno sheet is interesting.