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33 Posts
Discussion Starter · #1 ·
so I'm in the process of building a motor and this is what I've come up with so far .must pass smog in california

STOCK alumlnum heads (savin up for afr heads)
Block "zero" decked , stroker clearanced , bored/honed with torque plates etc etc
Eagle forged 383 crank
eagle forged I-beam 6 inch rods
SRP 16 CC dished pistons
Cometic 4.040 bore .040 comp thickness
crane 227 Cam, new in box. (got this for free)
Crane nsa 1.6 gold roller rockers free ( 2 missing 25 bucks each)
Comp 918 springs with locks and retainers
Edelbrock headers
2.5 cat back with x pipe
58mm TB
30lb injectors brand pn#s ?????(trick flow ok?)
2500 stall converter
3.42 gears (with stock size tires)
Tuning ?????
Anybody got any ideas on anything im missing????

4,506 Posts
I would stay away from Cometic gaskets. Heads and block would need to be very smooth for them to seal and most machine shops do not have the equipment/knowledge to do it correctly. Not to mention the stock heads. Felpro .039" gaskets are a cheaper and better alternative, if the block is truly zero decked. Otherwise, use stock iron .029" head gaskets for a better quench.

Do you have proper guideplates for the NSA rockers? Regular SBC guideplates are difficult to set up with LT1 heads unless you buy adjustable ones and tack-weld them. Self-aligned rockers are probably a better idea from the valvetrain geometry point of view considering the mild camshaft.

AFR heads are probably a waste of money considering the valvetrain. Even mildly ported stock aluminum heads will give you as much power with your setup and a better driveability. Well ported heads from LE/AI/reputable company will give you more power but you would need to upgrade the cam/valvetrain to take advantage of it.

Ford/SVO 30lbs injectors are a good idea because most tuners know how to tune for them.

F-Body MAF might be a good idea if you can find one cheap, but it is not required at those power levels with a good tune.

Stock fuel pump (unless it is new and has an external electrical harness) is not going to supply enough fuel, so I would budget in an upgrade from Walbro/Holley.

It is a good idea to upgrade the flexplate (find out whether the rotating assembly is internally or externally balanced). The stock one is externally balanced and has a tendency to crack due to extra torque.

A hands-on dyno tune from a reputable tuner will be absolutely required.

5,280 Posts
Just wanted to add your probably gonna have to clearance the shoulders of the Eagle I beam rods from hitting the 227 cam unless you get a cam on a small base circle.

You might want to check out a forged Eagle 383 kit with H beam rods which have better cam clearance.
Check this one out:


8,978 Posts

a mail order tune, done right, will be a key componet to not only running good but passing Calif smog. I have a mild 383 not far from your build and have passed every time. Ed Wright did it. If you have another qualified tuner you want to use on a dyno, fine.

I would just get the stock TB bored to 52 vs buying a 58.You may have low idle issues with the new motor and larger TB and if so drilling out the stock center hole 1/64" larger resolved for me. With stock heads this may not be a issue but before doing any drill mod scan motor to confirm what IAC counts are. If they are max (160 IIRC) than you will have to drill or slightly crack TB blades but the later can require sloting holes in the TPS.

Ford SVO 30's for injectors.

I Have not used the Cometec head gasket, just the FelPro 1074. After machine work on block & heads the quench should be about .038

Trick Flo PR are what I used. .080 thick wall hardened. you will need to confirm length and order the size you need. Often with decked blocked/heads you need a slightly shorter one. I use the ISKY adjustable guide plates. GM ones, for me, wore slots in themselves and never allowed dead nuts alignment on the valve tip. You can weld them togeather once installed but I never have without any issues.

I would maintain the windage tray so you will need to either use the Miloden extended main studs or re-use your 3 stock ones and just put a 1/8" washer between the studs, oil pump and tray to raise it up enough to clear rod bolts.

get a steel oil pump drive shaft. ARP makes one for around $12

You will make more power if you send the heads out to someone like Lloyd Elliott or advanced Induction. With the 227 you will have a mild TQ 383 that should pass smog easily with the right tune

get a Walbro 255 fuel pump


if just going 383 with stock A: heads with a valve spring upgrade like you note (918's) and running a 227 could just use stock TB, MAF, fuel pump & injectors. Just get a mail order tune and you should be fine. stock 350 LT1 with a 227 cam did not require/need larger TB, MAF, injectors or FP

the 383 will make more TQ and a few extra HP than a 350 would with identical mods, definately more TQ

Premium Member
8,695 Posts
Talk to LE about heads and cam package.

LE2 heads, cores, and cam are $1900. AFR can not touch that deal!

Llyod said this cam will pass CA smog:

224/230 .573/.568 112 LSA. – 1700-6100 RPM.
Largest emissions friendly cam. Pretty mild idle and still able to work with stock gears and factory converter in F or Y body.
Needs small stall and gears for B body. Comparable to GM Hot Cam and Crane 846 cam.
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