I have a small block 400 bored to a 406 with the stock heads that have been ported with 202, 160 valves, RPM intake that has been ported, a 508, 524 lift cam and 11:1 pistons. I also have a turbo 350 trans with a 3000 stall with a posi 3:73 gear. my question is why im I only running 12.9, shouldn't I run better then that.

 

How is your traction? Any idea of the weight of your car?

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"Rice burners are like tampons...Every pu$$y has to have one"
'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
3" Hooker CatBack w/Aero Chamber muffler
EDELBROCK 600CFM CARB.
KN AIRFILTER
ACCEL HEI DISTRIBUTOR
160* Stat, just switched to 180* b/c of winter coming and going to college in the mts.
3:73 Posi
Rebuilt 700R4
B&M Megashifter, 5" Autometer Tach w/shift lite

 

I think the real question is @ what MPH are you pulling down 12.9's. That will tell us your 1/4 et potentail.

I'm going to assume that you have 882 heads. I, too, had 2.02/1.6 valves put in them. After I pulled a rocker stud, I switched to DART Iron Eagle's, and the car woke up. The 200's would be a good choice.

 

the cars is about 2900 pounds and my traction was ok i had street radials on

 

I think the heads are 441 heads, atleast thats what the guy told me when i got them, and my mph was about 112

 

112mp with stock suspension components sounds about right.te new ls1's are running 13.1/13.2 @109-111mph.i would look into an adj.tq.arm and lca's.

 

112mph with stock suspension components sounds about right.the new ls1's are running 13.1/13.2 @108-111mph.i would look into an adj.tq.arm and lca's.

 

But shouldn't the car be pushing more then that or do u think even though the heads have the 202,160 valves they could be the problem because they are the stock heads or what do u think would be the best combo so i could reach mid 12 to high 11. the car is a 1982 trans am with stock suspension.

 

What were your 60ft times? If they are 2.0 or more, you are spinning off the line, hence your high ET. At 112, if you can hook it up you should be able to pull that ET down to a 12.5. Aftermarket LCAs, Torque arm, and LCA lowering brackets will do wonders for your traction. Some drag radial wouldnt hurt either.

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Mike Metzler (Desert86Roc)[*] Check Out:SpeedWorldMotorplex.com[*] Check Out:Chevrolet F-Body Online Part & Illustration Manual[*] My 86 IROC 305 TPI Page (406 build in progress)

ET's @ 1250 ft[*] 14.28 @ 95.461 mph (uncorrected, NOS, no headers)[*] 15.352 @ 91.215 mph (uncorrected, headers, no NOS)
<><

 

Ya my 60 ft times where at 2.0 and i was using drag radials sorry for the mistake when i said i had street radials. But could my stock heads still be causing some problems or are they ok.

 

I would say even with 441, the intake is at most 160cc maybe. With some bigger heads like TPI guy said, you would be happier. I would suggest 200-215. This may loose some torque, but with a stock suspension, you can only handle so much.



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Joshua Johnston
1991 Z-28
350, T-5, K&N, Ported Vortec heads, Edelbrock RPM, Holley 750 D.P., HEI, 11.07:1 CR, Comp Cams Roller-.510"/.520"-282*/288* dur., Shorty Headers, Dual 2.5 Exhaust, Dynomax Bullet Mufflers, T&R Motorsports custom air intake, Bald tires

 

441's are the old camel hump heads with NO assory holes, you would have to be running a pre 69' assory setup and none of your stock assorys would work, pull off a valve cover and get the i belive 7 digit number off them and i'll tell you what you got, stock 400 heads are garbage, and even a set of double humps ported will still not flow close to a dart or world head.

 

112mph is low 12s when traction is good. I imagine your car is a little heavier than 2900 (unless it is a complete race car).

I don't have anything in my car except 4 seats, power windows and locks and it was 3160 (and the only thing cast iron under my fiberglass hood is the block).

112 is a little better than 10 lbs per horsepower. Figure about 330 net hp. You could easlily get 50hp with a set of quality heads.

Work on weight transfer!!.

[This message has been edited by jcb999 (edited October 26, 2001).]

 

I'm building the same setup, does anyone make accessory brackets to relocate the p/s pump and alt? (See other post on this board)

Dan
Cameron NC

 

I have the same setup, it's not in the car at the moment but did spend about 10 years there though...

My 400 with the double-hump heads, however, has one of the castings (186) with the bolt holes.

AFAIK it is not possible to make brackets that would do that. The places that bolt holes would have to go would be almost paper-thin in places; you'd have to shave bolts down to the point that there would only be 1/8" or less going through the bracket. And you can't drill & tap the heads, because there's not nearly enough metal to hold a bolt, the casting isn't very thick there, and of course, the bolts would go straight into the water jacket.

People have been asking the bolt hole question since 1969. The answer was then, and still is, no. You'd think that if there was a way to do it, then someone would have figured it out in the last 30 years, but that doesn't appear to be the case. You simply have to have a set of heads with bolt holes if you want it to work right. Once in a while you run across somebody that has ethnically engineered something that sort of works, maybe one attempt out of 50 might succeed enough to hold a belt for more than 10 miles without something coming to pieces. But that's not the same thing as saying that it "works".

Ever wonder why those old heads are so cheap and plentiful nowadays, but ones that have the holes are rare and expensive? And no, none of my sets are for sale.

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"So many Mustangs, so little time..."
ICON Motorsports

 

OK Sorry im a rookie at this so what would be the best type of heads to get for the best price and what else could i do to get my self into low 12 even high 11 This is my first engine build up so im still learning THANKS

 

Well the head question comes directly down to money:

If you have a lot of money, you can go with whatever head you want. If not, you are going to have to sacrifice.

If you have the money, I would say the Fastburn GM Performance Parts heads are very stout heads that will support BIG power. The downside is that a new intake will be required and they are fairly small (62cc) so they may raise your compression ratio too much.. So maybe Brodix Track 1 heads would be better since they will bot directly in and flow nearly as well as the Fastburns.... Air Flow Research makes some great heads as well and offer a wide variety of intake port and chamber sizes... I think they can make them to your specs as well... not sure.....

If you are low on cash, you can look at getting some cast iron heads from World or Dart that will help that motor open up...

If you really want Aluminum, Trick Flow makes a pretty affordable aluminum head as well (that's why I got mine! ). My 23* TFS heads have 195cc intake ports, 64cc chambers, and 2.02/1.60 valves and run under $1000.... I haven't seen any actual flow numbers but I was told by a reputable source that they have similar flow characteristics to those of AFR 190s....

Well, those are some ideas for ya..... From the sounds of it, pretty much any of the aftermarket heads will yield good results on your engine over your current heads.....

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1987 GTA L98 MD8
355, TFS Heads, LT4 Hot Cam
My GTA

The Minnesota F-body Club

 

the only camel hump heads with the assory holes are the late 69' and 70 units, and people start riots to get a pair, sometimes getting the price in the 400$ range on cores! so really dollor for dollor some aftermarkets are the best deal to get.

 

What intake ports CC is the best and the same with the chamber CC.

What heads is the best
DART IRON EAGLE

Chevrolet: 262-400, 64cc, 200 cc intake valves, 1.437 in. 2.02/1.60 valves

Chevrolet: 262-400, 64cc, 200 cc intake 1.250 in. 2.02/1.60

Chevrolet: 262-400, 72cc, 200 cc intake 1.250 in. 2.02/1.60

Chevrolet: 262-400, 64cc, 215 cc intake runner, 2.05/1.60 diameter intake/exhaust valves, 1.437 in

Chevrolet: 262-400, 64cc, 215 cc intake runner, 2.05/1.60 diameter intake/exhaust valves, 1.550 in

Chevrolet: 262-400, 72cc, 215 cc intake runner, 2.05/1.60 diameter intake/exhaust valves, 1.437 in.

Chevrolet: 262-400, 64cc, 230 cc intake runner, 2.05/1.60 diameter intake/exhaust valves, 1.550 in.

TRICK FLOW 23's

Small Chevy: 1955-86 262-400, 64 cc, 1.47 in. diameter valve springs, 23 degree cylinder heads

Small Chevy: 1955-86 262-400, 64 cc, 1.25 in. diameter valve springs, 23 degree cylinder heads

 

Don't even think about getting a head with a 1.25 inch spring. The spring will not last long. All heads that have 1.50inch springs or bigger are really intended for roller cams (solid rollers).


Depending on your compression and your use of pump gas, I would get something at least 200cc intake (but not bigger than 215), a 1.44 (or .47) spring and a 68-70 cc chamber volume (for an aluminum head) and about 72cc for cast iron. That should give you close to 10.5 to 1 with a flat top.

The canfield is available in 72cc chambers as is the aluminum version of the iron eagle (called pro1). They are about $1000 complete from www.competitionproducts.com

Couple of other things:
The 1/8 inch larger bore on 400s can take better advantage of a larger intake valve. I like at least a 2.05 and a 2.08 is nice.

Also, have the heads set up for 7/16 inch studs. It reduces flex a lot.

[This message has been edited by jcb999 (edited October 27, 2001).]

 

Whatever you choose, make it aluminum heads, generally flow better and saves 40lbs, easier on your back. Get at least 200cc intake runners with that big 406. You're running a carb already so getting air to them shouldn't be your problem, it's all in the heads.

 

so my best bet is to get the TRICK FLOW 23's

Small Chevy: 1955-86 262-400, 64 cc, 1.47 in. diameter valve springs, 23 degree cylinder heads
with the 2.05 1.60 valves and a 200cc or 215cc chamber

 

I run older heads without the accessory holes with no problems. March makes a very nice kit that comes complete with new brackets and pulleys. It is fairly expensive but is a very nice kit and works great with early heads.

 

Exactly what cam are you running? I mean like grind number/company. Does the engine actually have an 11:1 CR with the combustion chambers you have? Its a common mistake to completely rely on the rated CR of the piston and not account for the head volume, let alone deck height, head gasket volume, etc. The intake should not have been ported. The Performer RPM intake works very well right out of the box. If the engine goes up in the 500+HP range don't bother porting it, other manifolds are better suited for an engine of that power. Your cam sounds radical from the lift, probably more radical than the porting on your heads allow. From the factory the iron heads peak out at about 0.400" lift. It is unlikely they are still improving flow at .500+ lift, even ported. So a smaller cam may give you more mid-range horsepower with only a tiny loss on the top end. The 3000RPM stall converter with the light car and 3.73 gears may require full slicks. You should improve 60ft times and overall 1/4 times by dropping the stall converter back down to 2500RPM or so. This is simply because the car won't try to launch as hard overpowering what traction you do have. But to be honest, 12.9 with stock heads is not a bad show. If you can throw out alot of details about the engine itself it could be helpful. I smell a little bit of mismatch giving you room to squeeze more. Despite stories of 600HP 350's and 400's with home ported 441 and 292 heads it is a very rare sight to see stock iron heads that will push you in to the 11's. If you want to see 11's it would be best to go with a good 190-200CC head. Stay away from some of the cheaper iron ones like the Sportsman II heads. They are only going to rob you of your money that could have been put towards a good set of heads. For good out of the box 11s potential try Dart's Iron Eagle 200cc heads or the AFR 195cc heads. Both are excellent performers that tend to not kill bottom end torque with their larger intake ports.

[This message has been edited by Dr. Pepper (edited October 27, 2001).]

 

from the limited info you gave i would say the times you're getting are from tourqe not hp.i would look into he 190cc afr heads.they have a great intake port concentrating on velocity.it will help out your tourqe big time with those heads and and adj.tourqe arm(get that first and work on your pinion angle)you'll be able to knock down 1.8's in your 60' and make up .3 in your 1/4.it's feasableto gain 1/2 sec.in the 1/4 justt from your suspension.good luck!

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87 trans am,gm crate 350(4 bolt mains 10to1),L98 aluminum heads,LT4 hot cam,slp runners,slp 1 5/8 headers,3in.y-pipe,edelbrock base,hi flo cat,air foil,afpr,as&m ported plenum,gutted airbox,t-5 tranny w/centerforce clutch and a 3.27 9bolt(11.9in. brakes),ed wright's fastchip,relocated iat sensor,160 fan switch&t-stat,tb bypass,accel supercoil,cap& rotor,slp 3in. catbcak,a/c delete.

SHE IS GONE BUT I KNOW THE GUY WILL GIVE HER A GOOD HOME.

best e/t:
3653lbs./full tank+ driver.
14.10@96.53mph 2.01 60'

 

Sorry about the limited info but I just bought the car and what I told you guys is what the guy told me the engine has on it. Im just trying to find out what would make this engine go better then what he got it 2 do. So far you guys have really helped me find out something that I can do to make it run the 1/4 a lot better so if I can talk to the guy again, not sure if I will beable to because he was moving I will try to get more info for it. SO THANK YOU FOR ALL THE HELP.
MIKE

 

i would get rid of that intake and buy a torker or a torker 2. another thing would be putting vortec heads or dart heads on.

 

[QUOTE]Originally posted by TempesT68:
[B]441's are the old camel hump heads with NO assory holes, you would have to be running a pre 69' assory setup and none of your stock assorys would work,

441s r not camel hump heads there early 70s large chamber 350 heads.camel hump heads are 461 462 291 186

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when the green flag drops the bull$hit stops

pulled the 350 to make way for the 406 wich is in the machine shop. got a comp 282S bump stick with 1.6 rockers. looking at differnt heads right now.Perfomer RPM and holley 650 DP, headers and 3 inch exhust. 3000 stall converter and a built 700r4. shotin for mid 12s next summer

 

i just stumbled onto this topic. i have a set of 461 double hump heads that i am going to put on my 406(the whole thing is in pieces)the 461 heads do not have the assc. holes factory. whoever had them before me, brazed a nut inside the head. so far, thats the only way i have heard of, or know of to put the later type assesory(sp?) the setup works just fine. 461 heads are 64cc and 1.94/1.60, they now have 2.02/1.60 and have been port matched and bowl hogged. i got them extremely cheap, so they are going on my 406 for the time being with a comp cams 274xtreme cam(comp cams recomended a 284xtreme but IMO i think thats wayyyyy to big)as far as good aftermarket heads, motown has a new set of 383-400 heads are freakin awesome, and they are only $980 or so. with there cam and those heads, 480hp at 5700rpm/500ft lbs around 3000. thats alot of power out of small block, especially power peaking at 5700. just my .02

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Wide Open Till You See God...Then Brake

 

CHP did a 406 buildup not too long ago that generated some good numbers.

It was a 406 with around 9.5:1 compression with a CompCams 274 cam (230/236 duration@.050, just under .500 lift). Heads were the 200 cc Dart Iron Eagles with a Performer RPM intake. 1 3/4" headers with no mufflers. Made 450 hp at 5300 rpm I believe it was and 500 ft-lbs at 4000 rpm.

I was kinda kicking around the idea of building a similar motor sometime here before too long, looks pretty impressive for the money. Nice power at usuable rpms.

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Ray87Z
-Vortec headed 350.
86 IROC w/ a cammed 305 TPI.
Formerly Ray86IROC.
www.inter-scape.com/Ray

 

What type of power do u think the engine would have with 11:1 compression instead of 9:1