OLDER ENGINE SPEC's

[X-TECH MAN]

If anyone is interested I recieved my old NHRA/IHRA engine spec book back today. I have spec's for most older combos for around 1984 and back showing cam duration, overlap spec's and valve spring pressures for those interested in IHRA pure stock. Same deal for older stockers for what ever combos NHRA will be allowing to run this coming year. I still need an old NHRA "Red Book" guide for the class breaks for the older cars if anyone who has one would loan one to me so I could make copies or at least offer to post any such info requested.

[Larry Hill]

Would you please post the spec's for the 428 1967 Shelby.

Thanks Larry

[vic guilmino]

1958 pontiac

[283nova]

66 283 220horse

[danny waters sr]

Now you won't be bored anymore Terry....lol

[X-TECH MAN]

Originally Posted by 283nova

66 283 220horse

1966 283/220 HP has a "rated" comp ratio of 9.25. Uses a Roch carb # 4GC-7025127 for a stick and 4 GC-7025126 for a P/G.
1.5 rockers Hyd. cam
54.9 CC's for the head and .002 deck
Flat top pistons w/ 4 valve relief's
Intake valve 1.725
Exhaust 1.505
Cam: zero checking clearence, 300 degress duration on I and Ex. with 78 degrees overlap.
.399 lift.
single spring w/damper
86 lbs closed spring pressure
180 open spring pressure
.018 head gasket

[X-TECH MAN]

Originally Posted by vic guilmino

1958 pontiac

Which HP version?

[X-TECH MAN]

Originally Posted by Larry Hill

Would you please post the spec's for the 428 1967 Shelby.

Thanks Larry

LOL We all know what I have in my old NHRA book isnt what is being run today.
Both of these are 428's.
The only single 4 version is listed at 355 HP. Uses a 4150 Holley carb.
.485 lift cam w/solid lifters.
68.0 CC heads
small exhaust valve @ 1.566. Intake @ 2.037
The rest is what is listed today by NHRA in the newer books
The 2 four version is 390 HPand uses 2 each 4160 Holley carbs
same head specs as above and a Hydraulic .481 cam.
The spring pressures and duration/overlap specs I have listed dont matter for today's NHRA rules for either one.

[Eric Merryfield]

Originally Posted by X-TECH MAN

If anyone is interested I recieved my old NHRA/IHRA engine spec book back today. I have spec's for most older combos for around 1984 and back showing cam duration, overlap spec's and valve spring pressures for those interested in IHRA pure stock. Same deal for older stockers for what ever combos NHRA will be allowing to run this coming year. I still need an old NHRA "Red Book" guide for the class breaks for the older cars if anyone who has one would loan one to me so I could make copies or at least offer to post any such info requested.

Thanks Terry,

How about 1970 dodge 383 in a challenger RT....the old stocker might just be pure stock legal! Valve spring pressure would be great to know.

Thanks again

Eric

[X-TECH MAN]

Originally Posted by Eric Merryfield

Thanks Terry,

How about 1970 dodge 383 in a challenger RT....the old stocker might just be pure stock legal! Valve spring pressure would be great to know.

Thanks again

Eric

There are 2 383's listed for the Challenger. I assume you wanted the 335 HP version. The other is a 330 HP with a different carb and a smaller cam.

1970 Dodge 383/335 HP
1 4 barrel Holley 4367 or 4217/sm 4369 or 4218/Auto
Manifold casting number 2951666
1.5 Rockers
Hydr. cam
Head CC's 79.5
Casting Numbers 906, 346, 213, 452, 902, 975, 187
Deck .004
Flat top piston
Head gasket .021
Single spring ( With Dampner)
128 lbs pressure on the seat
248 lbs open pressure
Cam: zero checking clearence
Intake 352 degrees
.455 lift
150 degrees overlap
Ehaust 380 degrees
.470 lift
Intake valve 2.080
Exhaust valve 1.740

Alt carbs 4667, 8, 88, 4734, 5, 6191 or 3