Wait for it......another "what will it make?"

-
Rat Patrol

Rat Patrol

Well-Known Member
Joined
Oct 30, 2010
Messages
1,245
Reaction score
62
Location
On the outskirts
My rebuild will be a step up....

318/392 factory cast block with SCAT forged crank and KB forged slugs

J heads with a 2.05 nailhead valve and ported - around 260ish at .550

Howards Hyd Roller - 288/294 adv, 235/[email protected], .530 lift, 110LSA 106 ICL

http://www.howardscams.com/chrysler/chrysler-v8-273-360-1965-1995-318-1967-1995#core2

M1 SP port matched, 800 AVS with choke bar removed, 1" super sucker

1.5 ratio Comp steel roller rockers

Crane HI 6 with 9mm ICE wires. Fully recurved DC tach drive dist

Clutch fan, factory water pump, HV oil pump

Crappy 1 5/8 tube off the shelf tri ys with a 2.5 collector,


Interested in any opinions?
 
Mal, there's a guy in Adelaide here that just had his 408 on an engine dyno, while on the dyno they swapped between a set of tri-y's and a set of morphett's 1.75" 4 into 1's. the result was around 3or 4 HP gain right at the top end with the 4 into 1's, so spend elswhere!
 
Hi Raymond - I'm happy to believe in most builds there'll be a difference...but I'm not convinced it'll be 30 Hp at our power levels.

Happy to be proved wrong though :)

Here's a giggle ...Camquest says 515 HP with a similar profile "Thumpr".....Yeah right. LOL!!
 
Will 2.05's fit with a 318 bore and no notching??
Imo cam is a little on the small side Knowing what your heads flow
What comp ??
 
G'day Ash..thanks for the interest.

My head builder doesn't seem think the bore will need notching - although he's going to give it a look.

Comp will be around 10.2:1. Open chamber heads and pump gas will limit what I can get away with.

Re size of the cam - My 3650 lb car was MPH -ing at 111 with a smaller cam and worse flowing heads.....and I'm only looking for 450/460 HP.

DD2003 says 469HP..with the roller.....but I think that may be "optimistic" with my crappy headers.
 
A 3" collector would certainly help, I have seen Pacemakers with a 3" collector near a real 500hp on various 360's. I ran what little data I you've supplied there through Pipemax and it spat out tri-y's at 1.737" x 18"-19" into a 1.862" x 18'-19" second segment with a 2.75"-3" 20" collector. (I assumed you had 10.5:1 and it would make peak power at 5500). If it was a 4 into 1 it would be 1 5/8" - 1 3/4" x 35.5" - 38.5" long with 3" - 3.25" x 20.4" collector.

Factory headed small blocks seem to love long collectors from what I have seen, I have seen instances of 20 hp, give or take from an incorrectly sized set of pipes. Pipes can be fickle on some engines unfortunately, pipes that should make big power haven't, and vice versa. Pipemax seems to get you pretty close.
 
Hey Al..thanks for doing those sums for me...very interesting.

(I assumed you had 10.5:1 and it would make peak power at 5500).
Click to expand...

Not far off. Good guess.

If it was a 4 into 1 it would be 1 5/8" - 1 3/4" x 35.5" - 38.5" long with 3" - 3.25" x 20.4" collector.
Click to expand...

Sounds pretty close to Dave Dart's pipes that he has for sale.

Factory headed small blocks seem to love long collectors from what I have seen,
Click to expand...

If worse comes to worse...I'll get a 3" collector tacked onto my existing Tr Y Pacemaker pipes, it may help in the short term..
 
You must log in or register to reply here.
-

Back
Top