Best Engine for Class Rules below, not Drag Racing

[Chris Hill]

Given the rules listed below for a truck pull class, what style engine do you think would be the best?

Classic big block Chevy
New style Chevy vortec engine (not sure how different these are from classic big block Chevy
Gen 3 Hemi (not sure if cast iron heads available)
Big LT-1 or LT-4 Chevy
LS style engine (not sure if cast iron heads available)

Thanks in advance. I'm just bored this weekend.

Chris


13. 485 cubic inch limit. OEM cast iron blocks and heads only. Must fit stock intake. No aluminum heads, any cam.

15. Aluminum intake allowed. No tunnel rams. No sheet metal intakes. One single four barrel carburetor allowed.

16. Headers must point down and back, parallel to the ground.

17. No after market fuel injection systems.

18. Illegal fuels: All forms of nitromethane, nitrous oxide, propylene, alcohol.

24. No dry sump motors. No external oil pumps. No vacuum pumps. No after market wet or dry sumps. OEM style oil pumps only.

25. Heads must remain in stock appearance on outside. Porting is allowed. No machining off the outside of head to install exhaust plates to raise ports.

Chris,

Are you going to Indy with momand dad this year?

[Billy Nees]

First thing that came to my mind was 429/460 Ford.

[Adger Smith]

429/460 = #25

I like the 70 mod LS-6 BB or even the '69 427 425 hp BB
The conventional vortec BB might work, I have no experience with those BB heads, but if they are as good an upgrade as the SB Vortec it might work.
The later Vortec 8100 has cast heads and could be the ticket, but it's 4.25 bore and 4.37 stroke makes it go about 10 over the cu in limit. Not sure if the induction would work, either. Destroke?
If you like later mods then the LS truck engine w/ iron heads:

Casting Number 373
Head: 1999-2000 LQ4 6.0 Litre Truck
Material: Cast Iron
Part Number:
12561873
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches
There is a thread on one of the LS forums that says the iron head can be made just as good as the LS-4 head can. There is a nice 4 BBl intake avaliable for them,too. Put those iron heads on a block with a larger bore and stroke it a little.. Let it fly!!
What is the most common engine being used?

[Daran Summerton]

429 was my first thought, scary! If you are limited to production cyl. heads find the Biggest made!

[Ed Fernandez]

Cummins in a Ram p/u.You did say pulling didn't you?:>):>):>)

[Alan Roehrich]

Provided you can run an OEM replacement block, such as a BowTie, and you're willing to spin the thing up, a 4.5 bore 9.8" deck BowTie block with a 3.76" stroke crank (396/427) gives you 478 cubic inches. You can get real close to a 6.7" rod in that, allowing you to run a really light piston with a good ring package.

A set of 990 castings for the heads, since it says OEM castings and no aluminum (you'd need a cylinder head guy capable of Super Stock national record holder quality work). Probably a Super Victor Dominator pattern intake, and since they allow any single four barrel carburetor, you could talk to the guys at Quick Fuel about a really big Dominator pattern carburetor.

I see no valve train rules, so I'd be looking at a big core (54MM) roller cam, 0.904" roller lifters, Jesel belt drive and shaft mount rockers.

You have a really good choice of parts when you run a combination like that. Of course, with that big bore, short stroke, and long rod, that's a high RPM (8500 or higher) and wheel speed combination, not a "dead hook" combination.

[Clay Arnett]

For truck pulling all these engine options are no good. 12 valve ISB Cummins only way to go!

[Mark Walton]

How about an iron headed 426 style Hemi?