Building NA 231...Suggestions??

M

Maxxod73

Guest
Hi everyone.....I am currently building a NA 231 in a 1986 Cutlass and need some suggestions or comments on the following combination....HP guesstimate would be helpful, will the cam/piston combo listed below cause clearence issues? Is there a good combination that would allow me to keep the ECM? and use a CCC carb and the 4.1 intake? I want to make at the least, 200-225 hp. The more the better:)

Buick 231 Block Casting # 25526109

Buick Heads Casting # 25518445 ported/polished/port matched/3 angle valve job......w/ 100 lb valve springs

Edelbrock Performer Buick V6 (non-EGR) #5486
NON CCC M4M Rochester Q-jet

Silvolite Buick 3.0L Flat top pistons - 10:1 compression????

Lunati Bracket Master II Camshaft / PN# 00252
Specs: Duration@.050 : 214°
Gross Valve Lift : .472"|.496"
Lobe separation : 112°

MSD 6A Ignition System and HEI coil
NON CC HEI Distributor

Holley/Hooker Headers
w/full 2.5 inch dual exh into 2 chamber Flowmasters

TH-200r4 swapped in place of TH200c

G-Force - 200R4 Racing Crossmember dual hump

2400-2800 stall Torque Converter non-lockup

3.73 gears and PowerTraxx Locker

Thanks for any help

John
 
Sounds Awesome! I think your target HP is rather conservative with that recipe. My 231 N/A project should get me 200-HP and it utilizes the 4.1 intake and Q-jet, (Modified), and it's all ECM controlled.

The cam is conservative, Kenne-Bell's MK-1L, (Duration@.050 : 204 degrees). Stock THM-350C and T/C, (the stock L-7 T/C sucks for launch).

*I believe that you will have clearance issues with those cam specs.

In addition I have the EST/HEI stock distributer with Performance Accell control module and MSD-AL6 ignition with a 48,000 volt coil from Summit. Pacer headers and stock 2.51 rear. Kenne-Bell oil pump gears, double roller timing chain, hi-rev lifters, Poston's 1.77 intake valves and stock exhaust valves, 3-angle valve job port and polished. No port matching...does'nt need it. Bored over.030, Kenne-Bell pistons.

So, as you can see....if one can get 200-HP with a conservative recipe like mine......yours should be way out there! :eek:

GOOD LUCk and KICK BUTT with that awesome Olds.....
 
I would stick with a lock-up TC...The D5 in this cars work good.
JMHO

Jim
Welcome aboard :)
 
Those 3.0 liter flat tops will give you something well over 12:1 compression...get some replacement 10:1 slugs meant for the '70 Buick 350. You'll see they are dished...GB
 
Hey Jim,

I'm still working on my website which will include all the images and mods I did on the engine. I'm currently piecing the engine back together again and taking snapshots along the way. It's a whole lot of work.

In addition, I'm rebuilding a pre-ECM Q-jet that I am going to experiment with in the late summer. The website will hopefully assist those whom want to rip out the CCC system and go basic. It's not really that difficult but it is involved. It's the little things that mean the world to such a conversion.

(I don't recommend this conversion on turbo's though. Although my knowledge of turbos is null. From what I've read this conversion can be detrimental to a turbo car.) :(
 
Hey Freddie...I really need to work on my site, need to add the mods I did to get a wastegate to fit and a few things not to do.
Work and house is keeping me pretty busy...mostly work, but I did know want I was getting myself into.
 
Hey thanks for the suggestions guys, this message board is the greatest, it will stop me from making too many mistakes :).....12:1 wow.....definatly too high, I was waay off some how. Do the Buick 350 pistons need any sort of special machining in order to work with the 231 conn rods?
Any suggestions on a cam that wouldn't cause clearance issues?
Im looking for more power, but dont want to loose too much vacume...I dont mind a lopey idle.....but it needs to be able to idle!!
The car is going to be a daily driver but will be seeing some 1/4 mile runs on summer weekends at Englishtown,NJ. I cant wait to run this car....I live about 15 mins from the track. I was originally gonna put an OLDS 350 in the car, but decided to be a little different and work the 231 to see what I can get out of it. Is there any thing I can do about the rocker arms/ rocker shaft? It looks a little wimpy and too light weight to handle any stress?
Thanks again Freddie, Unboosted and T-type!
 
Stock rockers are fine for any hydraulic cam. Piston/valve clearance hasn't been an issue, but valve guide/ spring retainer clearance is...I think the limit is .420" lift before machining is required. The smallest cam I ever used was a 224/224, .496" grind, so I never bothered to try one without cutting the guides. My current cam is a .620" solid roller, which still left plenty of piston clearance with 10:1 dishes, but not with my 12.2:1 flat tops. That 224 grind still had 12" vacuum at idle. GB
 
GB's right......the retainers hit the exhaust guides in excess of .420" on .231's up until 1984. I believe that the exhaust guides on the heads off of any '84-87 V-6 don't need to be cut down.

*I got that info out of a Kenne Bell book so yours might not need to be cut down if you wanna go a higher lobe. Give them a call and double check, (909) 941-0985. You don't have to buy their cam grinds, though they are excellant. I believe Crane also makes a good grind for this engine.

Also, page 80 of Pat Ganahl's book 'V-6 Performance' states that one has to machine the inside faces of the pin bosses on 350 pistons if you intend to use them on the .231. Any competant machinist with fair knowledge on these engines should know that. (Get the book....its cheap!)

As for the rockers, I got 3/4 copper couplers that are used for copper pipes and 8-bushing/spacers that slide onto the rocker shaft. That limits the side movement at higher RPM's. I learned this trick of of a Jim Ruggle's 'V-6 perfomance guide' that was graciously passed on to me by our moderator, Rich George, (nice guy :) ).

Have fun!:D
 
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