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Author Topic:   Heads/Carb
mrutrac
Dirt Roller

Total posts: 18
posted September 30, 2002 09:55 AM
Building imca hobby.

What is the better head to use....

Rules say - must be unaltered approved oem.
Numbers to choose from are... 014,195,267,330,336,339,388,393,441,445,454,487,493,545,598,624,642,709,799,813,862,881,882,920,991,993,997

Can someone rank, say the top 4 of the above numbers in terms of producing HP.

Also must run 2 barrel (no Holley) stock no altering except removing choke.

What roch carbs numbers are best with the restriction.

Are there better stock intake manifolds #'s to run also.

Thanks for the help

MrUtrac

hobby23
Dirt Full Roller

Total posts: 33
posted September 30, 2002 01:21 PM
in order best are 441,487x,882,993 are as good as your going to get in a 76 cc open chambered head.last three #s on 2 barrel carb 118 in part # on side of carb.last three #s on intake 752 in casting # in front of dist. any time

mrutrac
Dirt Roller

Total posts: 18
posted September 30, 2002 01:40 PM
Hey thanks hobby23...

I plan on running a manual 3 speed... rules say no lightened,corvette.... flywheel... Are they all basically the same weight? If no, what is better to run? part#'s help

Thanks

hobby23
Dirt Full Roller

Total posts: 33
posted September 30, 2002 03:37 PM
cant be much help there i run a glide .

Eljojo
Dirt Freak

Total posts: 273
posted September 30, 2002 06:55 PM
We had the same rule. Go to the dealer and ask him for a z 28 flywheel. Ha ha Same pn as the corvette! If you don't have a clutch diameter rule-try one of the 80's monza v8 pieces. That's a 9 1/2" which can be turned down by your local machine shop and the finished product weighs less than the stock corvette (oops I mean Camaro!)
On the head deal...I like the 441's best. My engine builder sats the 993's are better and I've heard good things about the 487's. A lot of guys seem to like the 883's but I've heard their biggest "pro" was availability. They have a reputation of not being a very good flowing casting and are prone to crack. Look on E-bay under " there is a set of 441's there now offered by Wheeler. Good luck!

Geffy95x
Dirt Maniac

Total posts: 122
posted October 01, 2002 12:25 AM
I've run a set of 441's for six years now and have been running with the big dog's, Ive heated the motor a few times over the years and have always had them re-worked in the off season and they have never been warped or cracked and that's money in the bank for me.

racer17j
Dirt Forum Champ
Total posts: 1565
posted October 01, 2002 01:11 AM UIN: 54865418
with imca they get kinda picky about the flywheels and stuff we always just run the flywheel and clutch off a 70's trucks. you can't run the nodular flywheels so thats about your only choice. as for a carb the ones off school buses are the best one but good luck finding one your best bet is to get on some sites like whowon.com or imca.com and get in the classifieds to find a good one that somebody that is moving up can no longer use as for the heads you'll probably be able to find some 882's pretty ez and they work good we run 6 cars out of our shop and they all have 882's on them never had a problem

mrutrac
Dirt Roller

Total posts: 18
posted October 01, 2002 05:50 AM
Many thanks to all! This forum is awesome!

This really helps with the many decisions one needs to make building a car.

MruTrac

Scoot
Dirt Freak

Total posts: 330
posted October 01, 2002 10:42 AM
From personal experience I would not run 882's. I ran a set for part of this year because I had nothing else to run. I had some problems with them. The guy that does all my machine work does not like them. The springs dont sit down in the seat, they use spacers, from what he tells me anyway.

------------------
Scoot
Smith Racing Team
870-365-5989

bncars10sen
Dirt Roller

Total posts: 13
posted October 05, 2002 08:39 AM
mr U

If i were you id try to use a set of 881s that have the 2.02s in them. If you cant find a set of those go with a set of 441s. Right now we run a set of 993s and we cut them to fit a bigger exhaust valves, and what a difference that made! Im assuming you have a vacuum rule? If you have the money Zero deck the block, that helps alot as well. We run IMCA sportsman class, we have a 15 inch vac rule at 700 RPM. There i go rambling again, anyways, Find a set of heads with 2.02int/1.60 exhaust. If youd like i can private message you with all the casting numbers of really good heads. Have fun in the next coming season!

glen73
Dirt Roller

Total posts: 25
posted October 10, 2002 10:35 PM
man,i like our track rules,but we are not imca,we all run double humps,mostly 461,462,but 492 castings are becoming really big here in oklahoma

Rvarc
Dirt Newbie

Total posts: 3
posted October 12, 2002 06:29 PM
If you can help it don't use 882's they are a hot running head.They are a cheap smog casting and when they built them they saved a penny by deleting the exaust cooling passages under the valve seats.I check all my heads for those opening and don't buy any that have them. If you were to stick your finger up the ports you will feel a opening in the roof of the port that don't help flow at all that is the deleted water passage and running a 500cfm you don't need any restrictions.Use a 993 it's a good head and a lot of times your motor will run cooler too.

mrutrac
Dirt Roller

Total posts: 18
posted October 14, 2002 07:29 AM
Hey Thanks everyone..... I picked up a set of 441 and 993 heads.... one more piece of the puzzle solved.... or at least I understand it better.

MruTrac

c21
Dirt Freak

Total posts: 346
posted October 14, 2002 11:49 AM
If by stating "no corvette flywheels" they are trying to keep you from running the 153 tooth 15 lb. nodular iron flywheel, you should consider looking for the 153 tooth heavier flywheel (25 lb. ? )that also came on some Camaros with 4 speeds (saw one on an 82 iroc not long ago). While this is heavy, it is lighter than the 168 tooth "truck" flywheel and can have quite a bit of material turned off of it's face to make it lighter still.... the greatest benifit is the lower MOI (moment of inertia) weight and it lets you use the 10.5" clutch (find a LUK pressure plate, stock replacement at only 13 lbs.).

Good Luck,
c21

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