Best way to proceed with improving up 427 Windsor street setup

[Ace23]

Originally Posted by blykins

252/262 @ .050"?

If that's duration at .050", that's a very large camshaft for a 427. My engines that are around this displacement and use hydraulic rollers have about 12-14 degrees less duration and peak at around 6000-6200.

My guess is that the cam has been changed sometime in the car's life and that cam does not match the rest of the engine/car/goals. Your compression test shows low because the cam is so large and the numbers actually jive for a cam that large.

I'm thinking that if these are .050" duration numbers, the cam is so big that you have no bottom end and you can't run high enough in the rpm range where the cam wants to be efficient.

If those numbers are advertised duration numbers, then that would be a tow truck cam....

I'd change the cam....

I will double check the build sheet that list the installed camshaft specifications as well as the sheet from Comp Cams. The previous owner had owned the car since 2009 but I cannot guarantee any changes prior to his ownership. I guess someone changin camshafts is as possible as anything else.

Originally Posted by DAVID GAGNARD

and the engine originally came with a dual plane intake and Davinci 950 carb.....now it has a Victor Jr. intake and another carb.....

Makes one wonder what else has been changed on the engine from the time it left the engine builder till now????????

David

I swapped the carb to a QuickFuel. I have a 150 page binder from when the car was brought in to the states and literally every receipt for the build and any additional parts through the years. Personally I think the motor is exactly what it says it is but thats something we can verify as the wrenches start turning. I haven' found anything on the car that hasn't matched up with the receipts......it was also a local car to me so the current group of guys in the Cobra club know that it hasn't been touched since 2009 when it was bought by the previous owner. None of the information I was given is a100% guarantee but it is better than not having any documentation on the vehicle

[Ace23]

I will update this thread as we go down the checklist on the possible issues. If we can't find anything we will pull the motor and then I guess we will all know for sure!

[blykins]

I don't think I'd pull the motor out....

I'd stick a piece of wire down a spark plug hole, verify the stroke is what it's supposed to be, verify the cam specs, and if they are what you say they were, I'd stick a hydraulic roller in there with 236-238° @ .050" and my bet is that you'd notice a ton of difference....

[DAVID GAGNARD]

Originally Posted by Ace23

I will double check the build sheet that list the installed camshaft specifications as well as the sheet from Comp Cams. The previous owner had owned the car since 2009 but I cannot guarantee any changes prior to his ownership. I guess someone changin camshafts is as possible as anything else.
I swapped the carb to a QuickFuel. I have a 150 page binder from when the car was brought in to the states and literally every receipt for the build and any additional parts through the years. Personally I think the motor is exactly what it says it is but thats something we can verify as the wrenches start turning. I haven' found anything on the car that hasn't matched up with the receipts......it was also a local car to me so the current group of guys in the Cobra club know that it hasn't been touched since 2009 when it was bought by the previous owner. None of the information I was given is a100% guarantee but it is better than not having any documentation on the vehicle

What concerns me is the Olthoff's tune/rwhp numbers correspond with the dyno numbers of the original engine,then thru the years things were changed and the engine "lost" about 100 hp......

Like Brent said,check the stroke,check the cam and see where your at and what you've got.........
Another question I would have is why was the intake changed and if the cam is not the original,why was it changed?????

David