427bbc upgrade-not a vette
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
427bbc upgrade-not a vette
Not a vette butt I've got a 1969 335hp 427 in my 1965 chevelle. I've looked through my chevelle forum but not a lot of 427's over there. Its my understanding this engine is similar to the 390HP version with the exception of a different camshaft and maybe carb too. Runs great now but mileage and internals are unknown. Does have a mild performance camshaft, performer rpm and 750DP carb, th400 stock converter and a 12 bolt with 3.90 GearS and running a 26" tire. Pulls strong up to 6200 rpms. Looking to keep the power band from about 2500-6200rpms. I've run solid cams and hydraulics so I'm open to either. I've always been a sbc guy so I'm unfamiliar with 427's.
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
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From: Citrus Heights CA
Yes I'm a long time member there but most guys are running a 496 or bigger and figured there are a lot more 427 set ups over here than there. Plus I dontdon't want to get hit with the "just build a 454 or 496" that happens just about any time someone asks about something outside the norm.
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
True... usually that means they dont really have any info to offer you outside of the ability to add a post to their count.
Had a 427 block yrs ago planned for mine was stolen from a body shop in S.Clarita. Love those BBs!! Decent set of heads, SFT cam or say one of Straubs HRs can get you in the 10s pretty easy.
Had a 427 block yrs ago planned for mine was stolen from a body shop in S.Clarita. Love those BBs!! Decent set of heads, SFT cam or say one of Straubs HRs can get you in the 10s pretty easy.
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
True... usually that means they dont really have any info to offer you outside of the ability to add a post to their count.
Had a 427 block yrs ago planned for mine was stolen from a body shop in S.Clarita. Love those BBs!! Decent set of heads, SFT cam or say one of Straubs HRs can get you in the 10s pretty easy.
Had a 427 block yrs ago planned for mine was stolen from a body shop in S.Clarita. Love those BBs!! Decent set of heads, SFT cam or say one of Straubs HRs can get you in the 10s pretty easy.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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427's are a heck of a lot of fun and can surprise lots of folks when done right. You might look over that Chevelle Forum right now...there's a 3900 lb El Camino posting mid 10's@125 MPH with a mild build. Unported import aluminum heads, a Comp street roller Holley intake and 4150 carb. Nothing too radical and runs like crazy.
You can make a lot of power with the OEM iron heads and some port work.
I still have my old 427 that I ran for 20+ years. Lots of different cams, heads, intakes and carbs over that time.
What do you want to do with it? Sticking with same gearing and converter?
JIM
You can make a lot of power with the OEM iron heads and some port work.
I still have my old 427 that I ran for 20+ years. Lots of different cams, heads, intakes and carbs over that time.
What do you want to do with it? Sticking with same gearing and converter?
JIM
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
427's are a heck of a lot of fun and can surprise lots of folks when done right. You might look over that Chevelle Forum right now...there's a 3900 lb El Camino posting mid 10's@125 MPH with a mild build. Unported import aluminum heads, a Comp street roller Holley intake and 4150 carb. Nothing too radical and runs like crazy.
You can make a lot of power with the OEM iron heads and some port work.
I still have my old 427 that I ran for 20+ years. Lots of different cams, heads, intakes and carbs over that time.
What do you want to do with it? Sticking with same gearing and converter?
JIM
You can make a lot of power with the OEM iron heads and some port work.
I still have my old 427 that I ran for 20+ years. Lots of different cams, heads, intakes and carbs over that time.
What do you want to do with it? Sticking with same gearing and converter?
JIM
As for my goals, kinda uncertain really. I think realistically I want to do a stock rebuild with stronger parts with a Cam upgrade. Still like that Crane 691 camshaft though.
Instructor
Joined: Oct 2007
Posts: 167
Likes: 1
From: Escondido CA
MEJ1990 is running the Isky Z-45 in the 402 and it runs great, I bet it would be sweet in a street bound 427. It's in the 240's at .050", even the -143 (L-72) cam ran great in that engine. Not sure about your pistons but my L-2300 have really shallow valve reliefs and can't run too much lift without fly cutting them.
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Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
MEJ1990 is running the Isky Z-45 in the 402 and it runs great, I bet it would be sweet in a street bound 427. It's in the 240's at .050", even the -143 (L-72) cam ran great in that engine. Not sure about your pistons but my L-2300 have really shallow valve reliefs and can't run too much lift without fly cutting them.
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
Isky Z-45 solid cam is 278-278 adv Dur and 244-244 @ .050, .530-.530 lift on a 108 lsa. Nice street cam for sure. Had one in a 62 Chevy p-u with a mild 396 and t-400. Ls6 #143 cam is 242-242 .520-.520 lift 114 lsa.
Last edited by wilcar; Oct 21, 2013 at 11:15 AM.
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
always made me wonder regarding Chevrolet and their HP ratings.. the 70 corvette LT1 corvette and the 70 Z28 Camaro are supposed to be the same engine but the ratings are different.. some say only because the Camaro's exhaust is not as free flowing.. I would guess that the corvette gets more HP claimed only due to it's name.
One would not think the 335 and the 390 HP 427 are the same, but without seeing the original cam specs, jet settings, pistons, exhaust, etc.. from both engines, it is hard to define.
I would like to see some true dyno runs ( verified..not manufactured by GM) of the published truly stock chevy engines.
One would not think the 335 and the 390 HP 427 are the same, but without seeing the original cam specs, jet settings, pistons, exhaust, etc.. from both engines, it is hard to define.
I would like to see some true dyno runs ( verified..not manufactured by GM) of the published truly stock chevy engines.
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
always made me wonder regarding Chevrolet and their HP ratings.. the 70 corvette LT1 corvette and the 70 Z28 Camaro are supposed to be the same engine but the ratings are different.. some say only because the Camaro's exhaust is not as free flowing.. I would guess that the corvette gets more HP claimed only due to it's name.
One would not think the 335 and the 390 HP 427 are the same, but without seeing the original cam specs, jet settings, pistons, exhaust, etc.. from both engines, it is hard to define.
I would like to see some true dyno runs ( verified..not manufactured by GM) of the published truly stock chevy engines.
One would not think the 335 and the 390 HP 427 are the same, but without seeing the original cam specs, jet settings, pistons, exhaust, etc.. from both engines, it is hard to define.
I would like to see some true dyno runs ( verified..not manufactured by GM) of the published truly stock chevy engines.
Instructor
Joined: Oct 2007
Posts: 167
Likes: 1
From: Escondido CA
The LS-1 427 used the 193/193 cam out of the L-35 396 with single exhaust IIRC. For minimal (comparitively) cash outlay I'd say you can have a serious street mill. If you can afford it I would really consider a roller cam though. Only recently have I had the cash to really throw any money at an engine so I completely get the budget deals.
Thread Starter
Cruising
Joined: Aug 2012
Posts: 13
Likes: 0
From: Citrus Heights CA
The LS-1 427 used the 193/193 cam out of the L-35 396 with single exhaust IIRC. For minimal (comparitively) cash outlay I'd say you can have a serious street mill. If you can afford it I would really consider a roller cam though. Only recently have I had the cash to really throw any money at an engine so I completely get the budget deals.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
I'll second that. I put 2.19 and 1.88 valves in a set of iron ovals once with good seat work and some mild porting. Things moved a lot of air and my 64 El Camino with a big block they went on ran like crazy!