Corvette 87 alu heads

[Guest jens]

How is these heads compared to the old iron 462 or mickey mouse heads. Is there any flow data and pocket porting info on the internet. I have following 70s el camino shortblock and 350 hp 327 cam that other parts than better valvesprings do i need to use them. and how fast would it be in a 240z with 3.7 lsd and 275-50 street tires

[Tim240z]

Call Scoggin Dickey and get a catalogue from them. Their cylinder head section has flow numbers on all the heads, GM and aftermarket. BTW, the Vortec heads flow better.

Tim

[grumpyvette]

the stock aluminum corvette heads flow about 190cfm @ .400 lift,thats close to what the old fuelie heads flowed (they are basically junk in stock form bye todays standards)but remember the stock TPI intake only flows about 210cfm and runs out of air at 4500rpm so the aluminum corvette heads were a good match to the intake they were designed to be used with. the vortec heads flow better at about 227cfm at the same lift, both heads are not up to the flow levels a good set of aftermarket heads have, but the vortecs are the better choice IF you keep in mind that they require lots of machine work and a new intake,valve covers,special rocker arms, etc if your serious about performance which boosts the price to the same level as aftermarket heads that are already set up to use the standard parts,use the high valve lifts and flow better look here

 

http://www.topher.net/~bearman/gmheadcomp.html

 

http://www.chevyhiperformance.com/editorial/article.jsp?id=41598&viewtype=text

(LOOK NEAR THE BOTTOM OF THE PAGE)

 

heres what a pocket port job normally does for the old fuelie heads

http://www.chevyhiperformance.com/editorial/article.jsp?id=41598&viewtype=text

 

heres what a set of pro-line heads and dart iron eagle heads with a minor cleanup will flow

 

http://www.dartheads.com/sbiron200.htm

 

http://www.procylinderheads.com/223200000a.asp

just keep in mind that youll need to spin the engine and spend most of your time in the rpm range that the cam you picks durration dictates (usually in the 5500-7000rpm range or higher)to effectively fill the cylinders and youll need to get a cam with about 235-245 dur@.050 lift and .500-.575 lift to take advantage of those better flowing ports if max hp is your goal if max torque is the goal a mildly reworked set of vortec heads and a cam with about 210-215 durration@.050 lift and .475 lift may be a great choice for a good low to mid range torque curve. btw a good air-gap style dual plane intake works well on most 327s, the single plane intakes due to the limited displacement tend to loose more low rpm torque that if they were used on a 383-406 sbc.

[Guest jens]

Thanks for the answers. Its a street engine so idle is very important. If i wanted 500 hp i would run a caddy 500. I have read that the L98 heads is good enough for 355 hp with performer rpm

comp cams 268 headders and a rochester. To pass inspection in dk i have to disengage the secondaries and put a restrictor in the exhaust. The rules says max 20% more hp = 180 in a z. The elcamino block has 170-180 hp and they look at the block number. If the idle is reasonable i can pass

inspection every second year just by tuning it down thats the way i have done before .

Is the alu version of the vortec head sold in cars or is it only aftermarket like the fast burn head.

[Guest Thurem]

Jens

I feel for you, and wish you luck getting thru inspection. Those guys in Rødovre once refused passing me cause i modified the rodpull, on the rear brake on my bike, to a cablepull. Another time the tester proceeded to rev the piss out of my cold RZ350 (2-stroke bike) with stock exhausts, in order to check for noise.

I think you should put a stroker crank in it to even out the idle and give you some more sneaky power.

Get even with the flippin bureaucrats, show them you are the boss.

Thure

[Guest Anonymous]

Jens: Please, keep us informed on that Caddy Z conversion thread