Rodeck engine

Well.....

L98 heads are horrible
The LT1 manifold is also restrictive, and runners are more in kind with a Vic Jr, so ram effect on the intake.
and your cam is pretty small.

The LT4, with only slightly worse exhaust, much better heads, a better intake, and 1 size smaller cam, made 330hp.

A ZZ4 with a similiar sized cam, a better intake and uncapped 1.75" headers makes 355.
 
guru said:
325 tops.............................
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not true guru,

high performance chevy put a set of ported L-98 heads on a base ie $1200 goodwrench engine with a flat tappet hydraulic cam Comp XE268 i believe and made 400 hp. They made the same with vortec heads but i prefer the lighweight stuff. In addition i will have another 50 cubic inches.

The goal is to have a nice performing street car that is light enough to go around corners. That is all.
 
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yeah, the L98 heads are good to about 400 HP if you rework them like in the Vizard book. They aren't even half bad. Also, not all L98 heads are equal, the later ones are much better than the early ones. The later have screw in studs and D port exhausts, the early ones do not.

Jim, buy the vizard book and rework the heads, you'll have a nice street machine when done.
 
Twin_Turbo said:
yeah, the L98 heads are good to about 400 HP if you rework them like in the Vizard book. They aren't even half bad. Also, not all L98 heads are equal, the later ones are much better than the early ones. The later have screw in studs and D port exhausts, the early ones do not.

Jim, buy the vizard book and rework the heads, you'll have a nice street machine when done.
Click to expand...

Well, the first L98's came out in '85 as we know, and from '87 VERTS ONLY, on up, they were aluminum, and AFAIK, all had the flat bottom exhaust ports....I think that's what meant by D port, as I recall....fucking information so seldom used get forgot....I need another beer and it's allready 12 noon....

:eek: so at any rate, they have flat ports on bottom and are #113 aluminum castings....I thought of porting/matching them but when holding the gaskets on there, it was SO freeking close, I decided to forgetaboutit....looked fairly decent from the factory....no EDEL casting, but still higher comp than the EDELs I had on there some years ago.....they had too big a chamber and so suffered in compression,....the iron heads on there were even worse....
this in fact is the FIRST set of decent heads on there yet...only maybe 3 years now...and the 10-x comp is felt good, and the timing has to be stock or it pingpongs where the others didn't...even on regular....hi test at 91+ seems ok though even lugging/locked up at ~40 mph and pressing the gas a bit...I can coax the tranny into doing that....

essentially I have a warmed over cam in a stock ZZ4 engine, really....

:fishing:
 
I think 86 verts only had the alu, all 87 up had them.

88 up had the D port exhaust, the earlier ones really did NOT have that. (P/N 12556463, or as a bare casting, P/N 10088113), the D port is also raised .100 from the std. location.
 
turtlevette said:
not true guru,

high performance chevy put a set of ported L-98 heads on a base ie $1200 goodwrench engine with a flat tappet hydraulic cam Comp XE268 i believe and made 400 hp. They made the same with vortec heads but i prefer the lighweight stuff. In addition i will have another 50 cubic inches.

The goal is to have a nice performing street car that is light enough to go around corners. That is all.
Click to expand...

Not disagreeing with you. L98 heads are pretty lame in stock form. Mr. Lingenfelter could get 400-450 out of them with extensive porting and larger valves, on a mild 383. But in stock form(depending on the year), they are an anemic at best head. They were designed to mate to the TPI get up and perform in the sub 5000rpm range on a 350. They are what they are. Sure you can strap them to a mule motor with huge headers, and a good flowing intake, with no accessories and make good numbers on any motor.
 
Twin_Turbo said:
I think 86 verts only had the alu, all 87 up had them.

88 up had the D port exhaust, the earlier ones really did NOT have that. (P/N 12556463, or as a bare casting, P/N 10088113), the D port is also raised .100 from the std. location.
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yup, you rite, '86 up verts then, then all of them, I had a '87 vert....I know the heads are 113 castings....and the ports are most deninately NOT round the bottom is flattened a good bit....

so I have to ass ume they are the D port heads??

not pulling it apart anyway just for shits and grins.....

:bonkers:
 
Twin_Turbo said:
yeah, the L98 heads are good to about 400 HP if you rework them like in the Vizard book. They aren't even half bad. Also, not all L98 heads are equal, the later ones are much better than the early ones. The later have screw in studs and D port exhausts, the early ones do not.

Jim, buy the vizard book and rework the heads, you'll have a nice street machine when done.
Click to expand...


Vizard-:thumbs:
 
I pretty much did the same thing as in Vizard's article except I didn't unshroud the valves in the combustion chamber and I replaced my valves with Manley valves instead of reworking the stock ones. Most of the work I did was around the valve areas and I only smoothed the rest of the port.

The last time I was on a chassis dyno I managed to obtain 328 rwhp even with a mechanical fan, waterpump, powersteering, full exhaust, and a cast iron flywheel. There is still more left in the motor because I was running lean (A/F ratio was 13.5:1 - 14:1), and I didn't have any bigger jets at the time. The first "blue" run was called off due to being REALLY lean.

vette_dyno_2005b.jpg
 
guru said:
Not disagreeing with you. L98 heads are pretty lame in stock form. Mr. Lingenfelter could get 400-450 out of them with extensive porting and larger valves, on a mild 383. But in stock form(depending on the year), they are an anemic at best head. They were designed to mate to the TPI get up and perform in the sub 5000rpm range on a 350. They are what they are. Sure you can strap them to a mule motor with huge headers, and a good flowing intake, with no accessories and make good numbers on any motor.
Click to expand...

I think I may dyno mine soon so we'll see how much I make with them
 
guru said:
http://cgi.ebay.com/ebaymotors/AVIA...71246QQrdZ1QQsspagenameZWDVW#ebayphotohosting

Probably more than you want to spend, but its 75% of everything you need. You would need a pan with 3 pickups.
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thats not an AVIAD pump it`s a Stock Car Products or a Weaver and that tank is worthless and useless, round yes but not horizontal mounting, the way a dry sump works the round tank needs to be vertical mounted....75% of what you need? what about a pan to fit a Corvette, front drive, hose, hose ends, oil cooler, screen filter...oh and a decent tank. Your also assuming that the pump is rebuildable and it has the correct size stages. ..................redvetracr
 
You also need to add either scavenge filters or filter inserts. The inserts only work on a pan with female (o ring boss) threads, if you have male threads you can use filter couplers from peterson, they also have them in 90 deg. elbow type. Otherwise you can just run the screen filters like from moroso and such.

Then there's a bunch of lines and scavenge manifold if you don't use a pump with an internal manifold.

The square block you see is a remote pressure regulator and it's very handy, reaching the adjustment screw on the pump can be a PITA, the remote one can obviously be mounted where you like. It uses a -12 feed and through and a -10 return.

You'll also need a remote filter or a block adapter w/ filter like from Barnes.

You'll need to remove the hidden plug in the rear vertical oil passage and you need to block off the cap, use a support strap that blocks it or get a new cap (which will be the most expensive way)

I agree with Howard, that tank is rubbish. You need a tall tank for proper de-aeration.

And then there are numerous hoses, hose ends, fittings, bulkheads, adapters...and so on.
The total will run in the thousands of dollars.
 
Twin_Turbo said:
You also need to add either scavenge filters or filter inserts. The inserts monly work on a pan with female (o ring boss) threads, if you ahve male threads you can use filter couplers from peterson, they also have them in 90 deg. elbow type. Otherwise you can jsut run the screen filters like from moroso and such.

Then there's a bunch of lines and scavenge manifold if you don't use a pump with an internal manifold.

The square block you see is a remote pressure regulator and it's very handy, reaching the adjsutment screw on the pump can be a PITA, the remote one can obviously be mounted where you like. It uses a -12 feed and through and a -10 return.

You'll also need a remote filter or a block adapter w/ filter like from Barnes.

You'll need to remove the hidden plug in the rear vertical oil passage and you need to block off the cap, use a support strap that blocks it or get a new cap (which will be the most expensive way)

I agree with Howard, that tank is rubbish. You need a tall tank for proper de-aeration.

And then there are numerous hoses, hose ends, fittings, bulkheads, adapters...and so on.
The total will run in the thousands of dollars.
Click to expand...

the downside of screens on the pan outlet is that they aren`t the easiest to access for cleaning, they tend to collect silicone, teflon tape and other non harmful stuff that wouldn`t hurt the pump but can clog the screens ultimately harming the pump. I run a remote screen filter (easily accessible, so I have no excuse not to maintain it) on the scavenge out side of the pump this line is also a -16 (price those hose ends sometime) also one -10 bullet style screen filter between the back of the block (scavenging the valley) and the third scavenge stage of the pump...In the old days most everyone used the factory oil filter pad drilling and tapping a hole for the "pressure in" just above the oil filter.
redvetracr
 
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Do you have 1 screen filter? I have 4 on each scavenge section and a large -16 on the retour line to the tank. They are easily removed for cleaning.

I don't see how the pan mounted filtering elements are harder to service than the ones inline somewhere else? The ones under near the pan are quite easy to get to.

if you use the factory pad, might as well chop the whole thing off and drill straight into the passage behind it.
 
I concluded that dry sump is too expensive for me

I'm sticking to the road race pan and I'll add an accusump

How would you like to buy a pump like these, very expensive

2i6qz4.jpg
 
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