dhirocz

iTrader: (2)

Resuming my max effort 427 TPI build. Get my shortblock back from the machine shop next week.
So far:
Bowtie block, #183, 4.125" bore, splayed caps
Manley 4" stroke crankshaft
scat 6" rods, capscrew, bushed
Weiseco forged pistons, 15cc dish
Custom cam, LS1 firing order, small base circle, billet hyd. roller
LT1 moroso pan (for low oil level sensor)

Plan is to use some larger cnc heads and a touched up FIRST with a modified plenum to accept a standard tpi throttle body.

Im looking into either econowolf 220 heads or the AFR 227 head. Im steering more towards the econowolf...seems to me to be a very stable port compared to the AFR, and I favor the I/E flow ratio more(throttle response and torque under the peak)

Fuel management will be via an 0411 pcm with a DBW throttle body and a 24X system. This will run through a C5 torque tube and T56 into my iroc...with a few mods here and there.

End goal is a fun to drive car, acceptable mileage, resemblance of the stock engine, mild manners, and instant gratification at the tickle of the giggle pedal. Something different, but keeping the original idea of the car while modernizing it.

At the conclusion of this, im reverse tilting the front end, like the c4 vette.

Thoughts?

1989GTATransAm

iTrader: (3)

"and a touched up FIRST with a modified plenum to accept a standard tpi throttle body"

I would touch it up a lot. See if Ken has the 2" runners available. Also nothing less than a 58mm throttle body. That 427 is going to want a lot of air. Normally I would say nothing less than AF 245 heads for a 427" motor but with the modded First TPI than maybe something less. You are going to have a ton of torque. I hope you have a stout drive train.

Orr89RocZ

iTrader: (20)

I like the econo airwolf heads and the regular airwolfs. I cant recall if they are RHS castings or Pro-filer. Econo one is imported core I think. Shouldnt need special parts but may need offset rockers depending on the size of the pushrod. AFR 227/235's are 60/40 spaced heads and I do believe need offset intake rockers. Either .050 min, or try a .150 offset intake. Also need to check the piston pockets for the altered valve spacing.

Econowolf's I do not believe are 60/40 spaced and should work with regular rockers but you will have to check. I know some guys have used offset rockers on them. Chad Speier also has some comparable heads... 227-235 cc now with an import core that makes them a great bang for the buck.

Either way, 2.5" min cross section for that motor, 220-235cc heads will work great.

88fastgta

iTrader: (9)

ken doesnt sell the 2 inch runners quite yet.... but i would get them if i had a 427sbc....

dhirocz

iTrader: (2)

Drivetrain isnt a problem. Itll take the abuse, if I were to ever abuse it.

I heard something about Ken working on a 2" runner project. Problem is I dont want to go TOO large. Want to keep the torque peak around 4000 rpm, hence the choice of the econowolf instead of the 245's. I figured at most it would be porting it up to size. If I remember correctly, keeping a 4000 rpm torque peak on a 427 cube engine required just at 1.75" runner diameter.

This is where I hit the fork in the road and need to make some decisions. I could justify pushing up the torque peak some, considering I am running a T56, and usually let the clutch out under normal driving around 1500. Off idle torque isnt as much of a factor as it would be for me with a 4L80-E.

dhirocz

iTrader: (2)

I believe they are overhauled procomps. Wouldnt suprise me if he goes so far as to replace seats and guides. I would hope so.

1989GTATransAm

iTrader: (3)

Those long runners are probably going to force a torque peak around 4000rpm. A 1.75" runner ID is small for that large of a motor. I sure would try to open them up some if you can.

SKELITOR117

iTrader: (3)

Subbing.

dhirocz

iTrader: (2)

I think I settled on the econowolf 220. I liked the AFR 190 vortec eliminators, but I think Id be leaving power on the table with a head that small.

I still need to call over there and talk out a few things with them. Been trying but havent gotten through yet. Another thing I like is the vortec bolt pattern on the heads. I tend to prefer the vortec engine's bolt pattern, as well as blocks for that matter. In any case, im going to ask what the possibilities are if I was to send over the first as well. I'll also be asking about port alignment on those heads which is a concern to me. I can port, but this is a max effort build and I cant compete with a decked out shop that does this daily.

Too bad I cant get extrude hone to work it through and give it some extra time with the abrasive. They usually dont take off much, they just clean up port imperfections. The first is a fairly clean casting so that would be a waste.

Orr89RocZ

iTrader: (20)

If you wanted a vortec head you may want to look into the GM bowtie large port vortecs and have someone do alittle work to them to best suite your engine. They make big power in stock form and respond to some good port shaping. I just dont think the 190 head is near large enough for a 427, even tho its a TPI intake. I'd feed it with some air.

1989GTATransAm

iTrader: (3)

"I'd feed it with some air."

Yep, a 427 requires lots of air. Look at the size of the heads used on a 427 BBC for instance.

dhirocz

iTrader: (2)

I agree. A 190 is just flat out too small.

Ive considered having some if the large port vortecs ported, but unless thats something I can get cnc'd at a reasonable price, Im not going to consider it. Trying to save a few pounds up front.

I want my head flow on par with intake flow. Also want to make sure port velocity is on target while maintaining the ideal CSA and runner length. It'll be fun, but Ive decided not to port myself. Normally I pocket port my heads and clean up the chambers at a minimum.

dhirocz

iTrader: (2)

Finally got ahold of Bryce today. He actually recommended the airwolf 220 to the econowolf. Considering its a Brodix casting and uses larger valves, im actually more comfortable with it after talking with him about it. I can tell by talking to him he knows his stuff, without a doubt, as expected from a man in his line of work.

Ill be sending him my first intake as well. I imagine it'll be in the ballpark of 1.8" ID by the time its ported, though that depends on the diameter needed for a 4500 RPM torque peak (which I decided on too, by the way). Forgot to ask him if he can replace the front plate on the plenum for the old throttle body, though Im sure he can.

Considering the extensive chassis modification required, I'm going to get some tuned length longtubes(with the stahl pattern) made to match the engine's powerband. I'm shooting for 600 ft./lbs. from this thing. I'm going to implement pressure wave termination chambers and I'm considering dumps through E-cutouts in front of the wheels just for fun. These will be true duals.

1989GTATransAm

iTrader: (3)

I went to Bryce's website and checked out the Airwolf 220 heads. I agree, that is a very good choice for your motor and set up. That should work out quite well. He should be able to get the runners to 1.9" ID with no problem. They are close to that in stock form. Same with the runner entrance into the base. Now you just need a cam to match.

dhirocz

iTrader: (2)

Yep, it'll need porting. 1.87" minimum lol air hungry bastard

Guest

pics....

dhirocz

iTrader: (2)

Nothing really to take pics of yet. The engine is still not assembled, just in pieces. I prefer to wait until I get the cam installed to put in the rotating assembly, to avoid knicking it.

Waiting on the cam to assemble the shortblock. Now that I determined the heads im going to use, I just need to confirm the runner ID and length with Bryce to get the cam going. It'll be interesting, with the LS1 firing order and everything...

dhirocz

iTrader: (2)

Heads, intake and port work are gonna run a buck or two. Dont want to wait to long, but gotta do it bit by bit as funds become available. The DBW setup, harness, reluctor, coils and such will.cost me a chunk too. It'll be a minute until she's ready to rock...

I'll put up pics as soon as I get the shortblock built. Roof has me busy this weekend...

articwhiteZ

iTrader: (56)

Im going to use the AFR 220 elmtrs (have them now)
had canton racing make me a pan 7qt w/the oil return lines and oil temp unit bungsw/dipstick that fit my 4" stroke. going to see what pushrods ill need soon. want to get it running in a few weeks

TORN

iTrader: (17)

I went with the AFR 210 cc heads on my 421 build. 3.85 stroke crank. Heads should be bolted on tomorrow after I drop in the last 4 pistons. I am going to run the First FFI setup on mine too.

TTOP350

iTrader: (8)

I'd be looking at a AFR 245 or step up to a 18* head if I were you.
I would have the 245s but they werent out yet soo I have the 235s on my 400 stroker..

Orr89RocZ

iTrader: (20)

AFR 220's are pretty good heads. I've seen a recent dyno on a pump gas race motor that made around 700hp. Not sure I believe it tho since the car doesnt quite run the ET/mph expected but they are good heads. 406 that rev'd out to mid 7000 rpm range. For that Rpm i'd have gone with the 235's but the 220's did well.

Any 400+ inch motor should consider atleast 210's but any stroker 400 should be well over 210, preferably 220-230 cc heads. Its a big inch motor that needs big airflow.