Still down on the dyno numbers :(

[Scott R]

OK, went back to CIS last week, driveability is perfect, hot cold starts are tip top, CO is dialed in perfect and hydrocarbons are low. So today I went back to the dyno for another set of pulls, and I hit 150 instead of 138, AFR's are in line with other peoples posts. I'll post the sheets in bit when my camera charges, however I'm disappointed, and I still think something is fundamentally wrong here.

I'm down to the basics at this point, ignition, which is always suspect, and maybe my exhaust. I'm not concerned with the muffler, it's a brand new MK 2 in 2 out, the SSI's I am though. The SSI's are designed for the 3.2l, and have the sleeves that fit into the heads, didn't think this was an issue, however in reading some other posts maybe I should have ground them off? I really do feel like I have an exhaust restriction, or something. Everything else is so spot on, rock solid idle, smooth power. anyone know?

[sjf911]

Have you rechecked the timing of your cams and double checked the lift/duration to make sure you have the right ones?

[mb911]

Wow! Is there a correction for altitude or something? your at 10,000 feet or so? There will definatly be a difference compared sea level

[BURN-BROS]

Scot, what is your ignition timing like? Can you post a link of what mods you have done to your motor?

[Scott R]

Originally Posted by BURN-BROS

Scot, what is your ignition timing like? Can you post a link of what mods you have done to your motor?

Cam timing is still not verified, I don't have a z-block, may have to leave that to the builder.

Mods are as follows:

9:8:2 JE Pistons on new Nikisil bores
964 Camgrinder cams
ARP hardware, rod bolts and ect
1980 CIS system all numbers verified
3.2L SSI's
M&K Gen 4 2 in 1 out
Freshly rebuilt 915
Everything else new, plugs, wires, anything that was removed at time of rebuild, sans the distributor.

EDIT: Sorry ignition timing is 5 deg before, per the sticker.

[VFR750]

Per this Link: http://wahiduddin.net/calc/calc_hp_dp.htm and todays weather, the dyno correction factor for Denver is 1.21

Therefor your 150 hp is really 181 at sea level, which is equivalent to 207 at the crankshaft

Seems like you engine is running great.

[Scott R]

Originally Posted by VFR750

Per this Link: http://wahiduddin.net/calc/calc_hp_dp.htm and todays weather, the dyno correction factor for Denver is 1.21

Therefor your 150 hp is really 181 at sea level, which is equivalent to 207 at the crankshaft

Seems like you engine is running great.

It does run great, could probably balance a wine glass on the fan strap, and it has a TON of power compared to before when it was near death. Here are the sheets.

[Jeff Alton]

It appears to be corrected for STP already. Have you checked that you are getting full ignition advance?

Cheers

[Scott R]

Originally Posted by Jeff Alton

It appears to be corrected for STP already. Have you checked that you are getting full ignition advance?

Cheers

Yes, 33 deg give or take a smidge.

[Steve@Rennsport]

Looks OK to me, given the late CIS (small runner) airbox and manifolding and considering your location.

Without question, those SSI's are sometimes a tad small for a 3.2 but your torque and HP curves look real nice for acceleration and "area under the curve". Thats a nice setup for a car living at 5000 ft+ altitude.

[Scott R]

Originally Posted by Steve@Rennsport

Looks OK to me, given the late CIS (small runner) airbox and manifolding and considering your location.

Without question, those SSI's are sometimes a tad small for a 3.2 but your torque and HP curves look real nice for acceleration and "area under the curve". Thats a nice setup for a car living at 5000 ft+ altitude.

Thanks Steve, it's a blast to drive right now, thanks for your expert opinion.

[Grady Clay]

Scott,

Your adventure is going to further inspire me to have an engine dyno available here again. Someone ‘borrowed’ my Stuska after I retired in ’86. I want to have another professional engine dyno setup available here.

My plan is to have one available to all the shops. I have discussed this with several owners. My goal is to have all the current diagnostic technology available to everyone.

My nice old Stuska helped hundreds (perhaps thousands) at Rennenhaus. I want to pass on what I learned.


Steve, Jerry, Dieter and many others discuss the use of an actual engine dyno compared to a chassis dyno. When researching an issue such as Scott’s and others, there is no comparison. An engine dyno tells the story and allows immediate adjustments.

Best,
Grady

[Scott R]

Originally Posted by Grady Clay

Scott,

Your adventure is going to further inspire me to have an engine dyno available here again. Someone ‘borrowed’ my Stuska after I retired in ’86. I want to have another professional engine dyno setup available here.

My plan is to have one available to all the shops. I have discussed this with several owners. My goal is to have all the current diagnostic technology available to everyone.

My nice old Stuska helped hundreds (perhaps thousands) at Rennenhaus. I want to pass on what I learned.


Steve, Jerry, Dieter and many others discuss the use of an actual engine dyno compared to a chassis dyno. When researching an issue such as Scott’s and others, there is no comparison. An engine dyno tells the story and allows immediate adjustments.

Best,
Grady

I look forward to this, I would gladly pull the engine to put it on a stand, let me be the first to "volunteer" per say.