Thread: any advice

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i have a 74 360 it's bored .060 over a little bigger cam i don't have the specs on right now if needed i can get them 1 3/4" headers and a holley 500 atop the stock intake ok i took it to the exhaust shop yesterday and they reccomended me running the 3" exhaust now that it is ran it seems to have lost "bottom end" tremendously would anyone have any thoughts on the matter without draining my wallet? would a jet change be in order? if so any recomendations? any info is surely appreciated.

A free flowing exhuast is a good thing on a car BUT you can have to much of a good thing. With 1 3/4" headers and a 3"exhuast you have a set up that is more suited for higher rpm hp,not lower rpm torque.

Hate to say it but i would change the pipes back to 2 1/4-2 1/2"

or maybe try a smaller diameter tube header.

man that's not quite what i was wanting to hear is ther any other way i'm running 10:1 compression they told me i might have to retune my engine, i wasn't figuring that extreme of a tune but if that is what it is gonna take i guess it will have to be done but i really don't want to go that far in depth.

going to bigger jets might help but i havent had that problem so i cant really say 100% so hopefully someone else might be able to give ya a few suggestions to try.

i appreciate the input i'm not looking for all the torque back but having to go to first gear to down to second gear to pull a hill is a bit much

Chappy this wont help find a way to improve your problem but take a look at this link,its pretty good discussion about the problem your having with too big of a exhuast.

http://www.4x4extremesports.com/inde...m/exhaust.html

Hey Chappy
Big exhaust rules. All you need to do is tune for it. Are you saying you have dual 3 inch now?

If you have a supposedly too large exhaust system, you will need to go with a bigger carb because the exhaust is exhaled quicker, therefore the intake has to be matched. Net result, more power! As it is, you are running too lean and too restricted on the intake side. Good luck!

yea that's correct i'm running dual 3" exhaust with a 2 1/2" crossover with warlock mufflers i pull this truck the class i pull in is restricted to a two barrel and the other guys are doing great with the 3" with similar setups i'm following what you're saying and i am very greatful i'm just trying to figure out what part of the puzzle i'm missing.

Check to see what jet size you are running. Does your carb have a power valve? Try going up four notches in jet size. Also make sure your fuel pump is putting out both volume and pressure.. All these things will cost almost no money to verify.

ok i'm running a holley fuel pump and a #73 main jet and a 4.5" power valve

Chappy, first of all, install a 6.5 power valve. #73 jets should be good but obviously aren’t. Are these the same jets you used prior to changing the exhaust, if they are, go up to size 76 for a day and then try 78s and in each case, check your plugs to see what color they are changing to. I imagine their current color is white or light tan. Tan is the color you want.

i haven't touched the carb after the exhaust change yet now that i have an idea of where i need to look i'll start playing i thank you all for the help i'm still open for anything else anyone might have to add

ok i'm looking at two different 6.5 power valves one says high flow would this one be the better pick