I've been shooting the breeze with my indy shop re having some engine work done over the winter. Right now, my 2005 low rider with stock 88 c.i. engine has 2-1 Supertrapp Kerker exhaust and a Ness stage II Big Sucker air cleaner. It's has a factory download (we think) for these mods and dynos at 77tq/71hp.

My indy guy quoted $1200 for cams, which includes the cams, power commander, labor, etc., and dyno tuning.

For just under $3000, he'll do a 95" big bore conversion which includes everything he'd do with the cams, increasing compression, plus the big bore part.

He can also ad head work but we never got around to pricing that.

My question is, what performance gains can one expect to see with each of the three listed sets of modifications: 1. cams, 2. 95" bb, 3. 95" bb with head work?

I realize each engine is different and there are different cams and myriad variables. I'm just looking for sound ballpark figures. For what it's worth, he suggested Red Shift 577 cams.

 

Are you getting it dyno tuned afterwards? If so you'll want to factor that in. If you're just going to do the bb and heads a year from now if you settle on just cams. .might as well do it all at once so you don't have to dyno it twice (3-500$$ each time depending).

 

From the numbers I've seen maybe +15hp for a cam, 7-8hp for big bore, and 5-10hp for heads. Cams will move the peak numbers around in the powerband depending on what cams you use, big bore will keep the powerband similar but move it straight up roughly, and heads usually help more on the top end. Your results may vary.

If you think you're going to do bore/heads down the road, pick your cam accordingly. But as mattVA said, its going to be cheaper to do it all at once.

 

Thanks for the comments/information. The prices include dyno tuning (or re-tuning) after the work has been done. Yes, a lot of labor cost can be saved by making as many changes as possible at one time.

Thanks for the numbers. Just the type of ballparking I was looking for.

 

Its a odd game - the more you spend the less you get.

Stage-1 is cheap and and you get a fair amount. Cams cost some more and net you a reasonable amount. After that you seem to have to spend a lot to get only a little more in return.

Personally I think stage-2 (zorst + A/C + cams + tune) is the sweet spot. You get the two biggest power boosts at a reasonable cost and don't reduce the life of the engine much. Its also doable yourself if you know one end of a wrench from another.

 

Those Red Shift 577s cams are recommended when you do the BB AND headwork. If you decide to skip the headwork, you should back off to the RS 575s or the 557s. Another thing to consider is if you decide to get your heads worked on, then your throttle body will probably be the "choke" point - might discuss that with your builder. There are several options to improve your tb - but always more $$.

 

The 2 best mods that gain you the most performance and the most for your $ are a good 2-1 exhaust & cams. You already have a god 2-1, so you're good there. I would do the cams & the tune for sure...it's worth it if you choose the right cam for how you ride.

Past that, it's all how much $ you want to spend. IMO, the gains from doing a big bore & headwork don't outweigh the cost, but that's JMO.

I did Wood cams and a D&D Fatcat with a good dyno tune & am very happy I stopped there. I will never tear into the motor past the cams, but that's just me. Everyone has an end point where they want to be for the $ they want to spend...I found mine & stopped as far as performance mods go. With the D&D, Wood TW-222 cams & dyno tune I'm +22hp/+18tq over stock on my 96"...she runs good & I'm very happy.

 

Appreciate the insights. I guess it wouldn't matter if the funds were unlimited but since they are not, it's good to hear from those who speak from experience.

alansummers, now that you've mentioned it, I remember that he only mentioned the 577 cams when he was discussing the "whole package" which inluded headwork. If I end up taking a smaller "first bite" I'll definitely make sure the cams are appropriate for what I'm doing. Seems though, that if I go for cams that don't "require" the headwork, and then later get headwork, I'd have to change cams again. I guess you have to pay to play.

Thanks again.

 

My impression is after the stage I is comp;ete you stand to gain about 10 hp/tq per 1000$ spent!up to stage II heads and BB kit with throttle body upgrade. after that as someone else said you start spending way more for little bits of performance increase. So the best I can suggest is to decide only once how much power you want. Sadly for most of us there is always something on the horizon!

 

I suppose at some point, and I'm not sure where that point is, it is more cost efficient to simply purchase a new engine from somewhere like S&S, because the new engine has everything that one would have added on to the old engine.

Hell, now I'm drifting my own thread.