Let me apologize for the long postright up front. For those that have a good memory I have given up on the crate motor due to funding at this time (Uncle Sam got me), I am going to do a top end rebuild to gain some horsepower. 1975, 350ci stock (at this time). Car is planned to be a Sunday driver, no track. I plan to use the stock quadrajet with either a Lars rebuild or rebuild by me using Lars paper. After some research on this site below is what I have planned with questions. All parts are from Summit.

Heads - NAL-12558060 (GM), 289.95 or
SUM-151124 (Summit), 324.50
I can't tell what the difference is between these two, thoughts one way or the other?

Intake - SUM 226018, Stage 1, 116.95 or
SUM 226019, Stage 3, 179.95
Again I can't tell difference between the two, looking for recommendations.

Cam - SUM K1103, 89.95

Lifters - SUM G6905, rollers, 159.50 or
SUM 141506, roller tip, 79.95
These are 1.5 lift not sure if I need this or 1.6 lift which have similar type rockers on the website.

Head Bolts - ARP 134-3601, 61.95
Head Gasket - FEL7733PT2, 17.95
Intake Bolts - ARP 434-2002, 25.95
Intake Gasket - FPP-1255, 20.95
Valve Cover Gasket - FEL-VS50088R, 19.95

Headers - SUM 69001, 89.95

Need
- Valve Covers
- Gasket sealer
- Carb rebuild kit
- Carb / Intake gasket

Questions
- Can I just change the cam out and not the cam bearings?
- What am I missing/forgetting? I have the water pump, alternator, ignition (stock) etc.

As you can see the cost of this rebuild can be from $1103.45 to $1315.10 or anywhere in between. Looking for recommendations on heads, intake, rocker combo's.

thanks.
scott

 

You can just change the cam while still using the same bearings. I really can't offer an opinion on your choice of parts, but what I do is copy a version of something Hot Rod has done (and dyno'd). I would take off the main caps and at least look at the bearings for obvious wear/damage and give the distributor a once over. But if you can't hammer it once in a while (for fear of the bottom dropping out) what's the point of extra power?

 

Thanks SH-60B. Anyone else?
scott

 

Is your 75 small block an L48 (lower compression dished pistons) or an L82 (higer comp flattops)?????? It matters.

Also ... are you using an OE or replacement Quadrajet carb?

Also ... is this (MY1975) car subject to tight smog scrutiny? Does 75 require EGR /smog pump in Cali?

 

foooz,
I had a '75 back in the early 80s as a daily driver which is/was the lowest horsepower Corvette produced except for the Blue Flames so I know what you're going through. I agree with SH-60B especially about his point regarding "if you can't hammer it once in a while (for fear of the bottom dropping out) what's the point of extra power?" If it were me...., I'd wait until I had the cash for a crate motor with new everything to include extra horsepower and warranty if it blows or a total rebuild to include the bottom end of the block and your choice of "go fast" parts.

 

Jackson - it is an L48, OE quadrajet and no smog requirements.

Jims66 - I am with you. I have read several posts that led me to believe I could perform these upgrades without too much risk of damaging the lower end. I do plan on getting on every once in awhile.

If I decide to go down this path are there other parts I am missing? Trying to order once.

Does anyone have recommendations on the specific items I am considering and how they will work together? From reading other posts I am anticipating about 300hp at the crank.

scott

 

Neither intake will fit a Qjet ... look for professional products p/n 52007 it fits Qjet & Vortec heads. Get the GM heads ... they're 64cc instead of 67cc ... you're gonna need the comp w/ dished L48 pistons. Wrong head gasket ... too thick ... get thin shim Fel Pro p/n 1094. Also, wrong rocker arms ... vortec heads require self-aligning ... this ain't a race car ... you don't need rollers ... get some stamped steel self-aligning OE takeoffs from ebay about $25 a set. Summit don't sell pp intake but you can find the pp52007 intake on ebay etc ... also I have a good used one for $75 firm ... email if you want it no dickering. You can buy similar edelbrock intake for nearly $200 ... not any better though. FYI ... late model heads (including vortecs) require different (centerbolt) valvecovers. Your old C3 heads have perimeter style VCs & won't fit vortecs.