Joer350

OK this is what I know have zz4 cam, pistons .040 over and siamesed runners and manifold and plenum.

What would be the guestimate hp on an l98 with a zz-4 cam and fresh engine at .040 over and compression ration at 10?

Same engine with mild ported heads and siamesed manifolds and runners and plenum?

Would dual roller timing chain have any increase?

Also possibly considering 1.6 RR's what would be the hp gain over stock?

Sorry to ask all of this but after all the time I have put in this engine I want to know where my power is arround


Also what would be the cost of getting my car on a chasis dyno?

flyersfan1088

I can't give any educated guess on what your numbers will be, but i can tell you going to 1.6 RR will give you anywhere from 5-15hp depending on the rest of the combo.
Dyno prices vary by region. In Missouri, they range from 75-110 for 3-4 pulls. If I had to guess, I would say Ca would be slightly higher, but it's worth it since that's the only real way to tell.

65Z01

A ZZ-9 cam can be worth 30chp so I would expect the ZZ-4 to give a little less.

Worked #113 heads are worth 25-30chp.

RRs with the ZZ-4 cam should be worth 10-15chp.

Siamese runners or siamese base will improve upper end breathing at the expense of some low end. My siamese base with stock size runners netted a 20chp gain at 5,400rpm with some unknown low end loss (with my A4 the dyno pulls started around 3,500rpm).

Of course you should have a free flowing exhaust, including FL headers the mods you are discussing.

Also, an AFPR will be needed to add fuel at WOT.

Joer350

the thing that sucks is that I live in ca so I can't get FL headers.
But a cat back is in order and maybe cutting back the spark plugs