Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (
-   Hotrodding Basics (
-   -   454 race build (

optimus 02-21-2012 09:39 PM

454 race build
hows everyone doing?

I am starting off on a new project that's completely new for me I'm building my first BBC. and just to make sure i get all the hard stuff in on my first build i'm going to top it off with a weiand 6-71 supercharger. so I may be asking for alot of help in the coming weeks.

but at the moment I'm just getting it ready for the machine shop.

the block is a gen IV 454 I don't know yet if it has 4 bolt or 2 bolt mains.

when i get it to the machine shop other than cleaning manufluxing and maybe punching it .030 over is there anything special that needs to be done to a big block?

i have done several SBC's but like i said I'm new to big blocks.

I'm also not to sure on the heads yet but I'm hoping they are 118cc
target compression is going to be around 9:1 I'll be running dual holly 750 dp's
on race fuel NOT PUMP GAS
this is not going to be a street car It's a 77 nova that's full race
currently it will be backed by a th350 tranny with a 4500 stall converter and 12 bolt Chevy posi with 4.88 gears

I'm hoping to get around 750-800 hp
any suggestions on cam combinations or anything else I need to know to help me from messing up on this build?

any help is greatly appreciated

James from Kermit TX.

Mr. P-Body 02-22-2012 07:09 AM

Building a BBC to make 700-800 HP "with compression" will not require a blower. In fact, if CID is over 450 or so, a 6-71 will slow it down... An 8-71 MIGHT work a bit better, but a 14-71 is truly"full race". By today's "standards", a 6-71 is a street component.

Stroke it to 496. Use the best heads you can afford. We "like" Brodix and Dart here. If your budget can "stand" it, go for a "spread port" head like Big Chief or Big Duke. If not, stick with the aforementioned brands. Avoid "price" shopping. You can't get "the good stuff" cheaply. Since you want to supercharge this engine, be sure ONLY a high quality porter does your heads. Contrary to popular belief, port work is MORE important in blown applications than in N/A engines. It doesn't need to be much "bigger", but the paths need to be clear and relatively smooth. Each obstruction will inject significant heat into the mixture, costing power and efficiency.

We have success with Eagle rotating "kits", but have heard of others having dimensional issues. For imported engine parts, Eagle is the best (IMO). Their 4340 cranks are VERY nice, and TOUGH. Use the longest rod that will "fit". For power levels over 1,500 HP, we need to talk... (:-

You might also consider a mechanical injector over the two 4-bbls. Enderle is currently the hot lick along with Waterman. These are especially effective when running methanol for fuel, but do offer far superior performance over both carbs and EFI regardless of fuel type.



optimus 02-22-2012 07:48 PM

I was planning on using the 6-71 to start with because It's not costing me anything if it doesn't work out I'll buy a bigger one.

As far as heads I can't afford $1,200 a head but I have been doing alot of reading on these pro comp heads and yes i know where the casts come from and yes i would rather have american made but I'm only using the bare cast everything else installed on them will be done here in the USA.

I am considering this cam

with a good set of roller rockers.

this is all being done on a modest budget mostly because my wife would kill me if i go overboard. I do have a bad habit of getting carried away.

optimus 02-26-2012 11:32 PM

change of plans
well the deal fell through on the blower so i have decided to stroke it to 496 already ordered a scat crank 4.25 stoke and some forged H beam 6.385 rods what compression ratio would you recommend with 115cc heads? same heads as in the link in post above. I am changing the cam setup also this one I believe will work well with the setup. with 3/8 push rods and 1.7 ratio roller rockers to top it off. any other things i need to look into or change?

thanks in advance

327NUT 02-27-2012 12:18 AM

No offense but you need to slow down and discuss your build with a performance engine builder. You don't want to buy a cam before you know what your compression will be.

optimus 02-28-2012 11:27 PM

well i haven't bought the cam yet that's just what I'm looking at...

however with a 4.25'' stroke crank and 6.385'' rods and 115cc heads and these pistons my compression should be around 9.9-1 +/- not sure yet how much the machine shop will have to remove to deck the block but I was thinking and correct me if I'm wrong but with the dome top piston and the longer stroke if I run the bigger lift cam, I run more risk of slapping a valve with a piston. I might be wrong but I was asking for advice on the cam because there are alot of people on here that know alot more than I do. and I would much rather do it right the first time... That said I am open to suggestions and do need to order my pistons quickly so I can get them to the machine shop before they do the final hone on the block so if i should need bigger or smaller pistons I need input by Friday morning..

thanks James

optimus 08-08-2012 01:32 AM

it runs
it's been a while sense i have posted anything so i'll update...

I only bored it .30 over so it's actually a 486 but it is up and running.

I went with a TH400 tranny kevlar plates 32 sprag with reverse manual valve body that should handle my HP with no problems and a 2200+- stall..

I'm not sure on what HP it's going to make yet calculators put it at 700.

I'll be at test and tune this friday to try it out.

wish me luck and i'll post my et later

zildjian4life218 08-08-2012 08:54 AM

Good luck to ya! Bring someone along to take some pics and videos of it going down the track!

vinniekq2 08-08-2012 10:33 AM

have fun,,

WesTex Hot Rods 08-08-2012 01:09 PM

Just read your thread, I'm in Odessa & plan to go out to Caprock this weekend if I don't end up working. What color is your Nova? Good luck by the way.

optimus 08-25-2012 04:09 PM

this isn't good
Ok guys I need some input on this I took it to desert thunder our local 1/8 mile track and made 3 passes not being to hard on the engine because it is fresh. after the third pass my wife and some guys that were watching said it started smoking during the pass. I did some looking and found a wet spark plug #3 cylinder I pulled the valve cover off and found the intake rocker was loose (stud backed out of the head) checked the threads reinstalled set valve lash fired up all was good no smoke. made another pass with a small amount of smoke at the end of the run so i loaded the car up took it home and pulled all the rocker studs thread locked (red) and put it all back together ran perfect.

yesterday 8-24-12 I took the car to caprock motorplex made 1 pass and halfway down the track the engine started backfiring through the carb I could see the flames under the cowl. before I could hit the kill switch the engine DIED.
after i towed the car back to the pit I pulled dist. its fine gear is good looked at gear on cam while cranking and no movement so it looks like the timing chain snapped. this is the chain I have on it Cloyes Gear C-3024X - Cloyes Heavy-Duty Timing Sets - Overview - cam is comp cams lift is around 560 intake/exhaust pistons are 39cc dome tops with intake valve relief what are the odds that I can change the timing set and be good to go? Or is it more like slapped / bent valves pushrods = rebuilding this New engine.......

sorry for the long post but information is a good thing most of the time right

James B.

optimus 08-25-2012 04:20 PM

1 Attachment(s)
here is a pic of my car

cdminter59 08-25-2012 10:55 PM

454 race build
I would pull the heads to see if you had valve to piston contact. Check the pushrods by rolling on flat surface. What is the brand and part# of the pistons?What is the Part# of the camshaft? Also do these 115cc chamber heads have casting numbers? If any valves are bent sometimes they will not close all the way. I have used Cloyes Timing chain sets with no problems. Post back of what you find!

optimus 09-30-2012 12:03 PM

not the timing chain
ok so it wasn't the timing chain that broke it was a lifter. it exploded and caused the cam to snap in half I haven't pulled the heads yet so i'm not sure on the extent of the damage but it will definitely be spending the winter on the engine stand being rebuilt...

any ideas on a cause for this?

hydraulic lifters

vinniekq2 09-30-2012 12:37 PM

Ive had 1 hydraulic lifter come apart in forever.I wonder if it was damaged when the rocker stud backed out? Sounds like a thourough inspection around cam bearings and lifter bores is in order.If the track is open I personally would throw in a new stick and race unless huge damage is apparent.scope the bearings.

was there a lot of broken metal from the cam that is now in the pan?

All times are GMT -6. The time now is 02:07 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.