[AdamCali65]

Hey all,

So I've got a 351w thats basically stock (I think the cam is slightly bigger than stock but I could be wrong so lets assume its stock) except for a Edelbrock 650cfm carb and Edelbrock intake. I'm now trying to move up to heads and I'm looking at the E street heads (not going to be a power monster more of just some more power for cruising etc). What gains could I expect from E Street heads when added to the intake and carb upgrade? What about a cam (the cam I wanted to put in isnt much bigger than stock and its as big as I can go before converter work and rear end upgrades which are eventually planned). So the E streets on top of the stock 351w added to the intake and carb, is 30hp too much to expect? Thanks.

 

[Beechkid]

Hi Guy!

Before looking into heads, etc, the 1st thing you need to do is to establish what/how/where you want the engine to perform, and this starts with the following questions...I will somewhat answer these as I go to give insight and of course you can vary this to suit your own needs.....

1) vehicle use- street, weekend cruiser, idle must be good, ranging from oem smooth to slight lope
2) power band (peak power)- 2000 rpm to 5500 rpm, redline not to exceed 6000
3) The first step once you have this decided is to contact a cam grinder.........the cam is the heart of the engine and tells it when & where & how much to breath....swapping heads just for the sake of swapping heads is well, kinda non productive and at worst may very well work against you especially if you don't know the specs on the current cam that you plan on keeping.
4) Once the cam grinder knows what you have (including diff gears, torque converter specs, etc), what you want, they will determine the specs for the cam , make recommendations for valve size, etc and will even make recommendation on CFM flow...and likely have specific recommendations of potential heads to purchase (Trick Flow is typically one of the better flowing heads for SBF street engines)
5) Now you can start buying products to make thing work.

The SBF heads are pretty much all the same in terms of need.....a 4 angle vale job, increased flow and that will make the engine happy.....but, you can also typically purchase new heads for not much more that have all the goos completed and are aluminum.

 

[AdamCali65]

Thanks for the reply.

So the car is driven just on the weekends, I am looking for some more power nothing super high powered and major in the idle-5500 rpm range. I decided on the heads I want as they are good mild heads, 1.90/1.60 intakes, 210cc runners 160cc exhaust runners 60cc combustion chambers etc. As far as the cam goes I selected a while back the XE256H because it is a mild street cam and any bigger I'd start having to play around with my converter and rear end.

My question was basically, does a 30hp gain in just the heads sound reasonable? From the cast iron, 1975 smog era heads (with the infamously bad exhaust ports) and moving up to the Edelbrock E Street heads, is 30hp gain just from the head swap reasonable?

Then in terms of the cam choice, I kind of have it figured out and all I was wondering about the heads since I'm going to do the cam a little bit more down the line. Probably better to do it all at once, but its all good, I can pretty much do it whenever.

 

[seph10]

This may be something of interest to you, (this is only a suggestion) you may be able to find a similar top end kit else were, Edelbrock 2092 Mustang 351W Top End Kit 400 HP Engine Kit,

 

[Lizer]

30 hp wouldn't be an unreasonable expectation, but how much will you really feel it? What gives you that seat of the pants feel is torque, and fortunately torque is usually max at an RPM range you spend more time in, such as 3000 rpm. Your full 30 horses gained wouldn't be completely realized until around 5000rpm. Dollar for dollar, to make your car feel like you just added 50 hp, the best upgrade you can do is put taller gears in the rear end. Your acceleration will be much improved off the line.


Sent from AutoGuide.com Free App

 

[AdamCali65]

Yeah I've been considering a set of 3.73s for a while, but wasn't sure if I should first build up my motor more or address the rear gears...both will get done eventually though.

 

[AdamCali65]

Currently my gears are 2.80s I think however, I am going to bump that up in the next few weeks to a set of 3.55 gears. The exhaust is a flowmaster dual exhaust and has manifolds not headers. Was going to plan on trying the headman swap headers soon enough though. Those have a 1 5/8' primary set up but only 1/4' flanges (I was hoping for 3/8" flanges but apparently these fit quite well). I was planning on just using 1.6 ratio roller rockers from comp cams, and now with mu recent choice to go for a 3.55 gear I might bump up to the 262h or 270h.

 

[AdamCali65]

Yeah for a while I was also considering the 262H but due to my lack of proper rear gearing I had to throw it off my options list. Thanks for the help, I'll for sure go with that cam now that I can.