Rob 97 Z28

iTrader: (3)

Heres a purposed mild budget for my DD when I return from the sandbox...


*rebuilt bottom end (summit 87-95 305 kit which inludes new pistons,) new PR's and lifters (OEM)

*TPI 081 heads (ported, 3* VJ, slightly milled, new LT1 valve springs)

*LT1 cam (preferably 92-93)

*Hedman LT's, ORY and Flowmaters 40 series


I know it sounds generic, very probably. But what I am interested in knowing is:

A) Is there anything I need to know about with the 081 heads.
Will they work well with my edelbrock performer intake?

B) Will the 600 cfm Edelbrock be able to support the heads and cam setup (lean conditions?)?

C) Has anyone else run this set up?

D) I ask about the 081 because there seems to be alot of good deals on them here and the other sites. Just for a dd budget build i figured they'd be a good bang for the buck.

*What are the differences between the 85-86 081 heads and the 87-92?

*Is it just that the earlier style have guides?



E) I believe I read somewhere that the 92-93 LT1 cam was the hottest (highest lift) of the LT1's (don't feel like trying to find a LT4 cam at rock bottom price lol)

*Can anyone confirm this or advise what year shows the best gains?

*Assuming I would be able to run this carbed set up with an EFI cam, would I have to retard my base timing to compensate for the fact that hydrlc. roller cams have a faster ramp rate and may be to "fast" for the carb?


Can anyone recommend PR length for this setup?

The stock TBI and ECM was completely taken out of the car yet it retains the stock fuel pump thus i can fun an GM EFI cam. Atleast things have beenworking fine so far...




Thanks for any and all suggestions!!

Fionnla

You were asking questions about the LT1 Cams.

1993-94 Camaro/Firebird LT1.
Cam Part# 12551705 (Hot Cam)
Lift-.449/.460. Duration @ .050 - 207/215. Lobe Sep-116.

1994-96 Caprice & Impala LT1.
Cam Part# 10243779
Lift-.418/.430. Duration @ .050 - 192/196. Lobe Sep-111

Both are Roller Cams.

Good Luck on your Project.

Stay safe in the Sand Box.

InfernalVortex

iTrader: (4)

85-86 heads are perimeter bolt. 87-92 are center bolt. The intake manifold bolts are at a different angle also. Most intakes on the market dont play nice with centerbolt intake manifold angles so you have to buy little grommets (I think?) or something, or you can elongate the holes.

I avoided the whole thing entirely with my build since I got a GMPP intake for my Vortec heads and they're already set up for that.


See how the intake bolts go straight down into the heads? The old style bolts go into the heads at the same angle as the flange on the intake, ie, the heads of the bolts match the angle of the port face of the heads. Most intakes on the market dont have the flat surface for the bolt heads to properly grab onto them from what I undestand, so you have to get a little creative with it.

Not a big problem by any stretch, but just something you'll have to deal with. So if you look for a set of heads, it might be a good idea to look for an 85-86 set.

Also, if you're going to rebuild the bottom end, that usually means machine work to get the block freshened up. You dont want to put a new rotating assembly into worn out bores. You can, it's just kind of half-assed that way.

So if you're messing with teh shortblock, maybe you should consider trying to find a 350 core somewhere and using that? Machinework costs the same, rotatin assemblies cost the same for the most part. You're not really saving that much money by staying with what you got. 350 cores are cheap and common as dirt.

Sticking with hte 305 is great when you're trying to stay on a budget, but the minute you mess with the bottom end you need to take a step back and realize that that money could be better spent on the 4 inch bore kit.

Unless it's just running terribly, I'd go ahead and do all your mods to the 305 bottom end as it stands. I mean lets be honest, these L03s just don't go through that much stress in their lives putting 130hp to the wheels, and I think that's why they last so long.

So I'd just leave the shortblock alone and bolt all the new goodies to it as is.

Rob 97 Z28

iTrader: (3)

Thanks for all he replies!


I appreciate all and any input. Ofcourse I would have the block cleaned up, honed, and magnafluxed just to makesure everything was okay. I know the whole 305 Vs 350 rebuild thing. I wanna rebuild the 305 for a few reasons.

First off i kinda wanna keep it an L03 car just with a heads/cam/intake upgrade i know everyones thinking Second reasoning is that im paying off my '02, buying a house and a 400+ piece toolset & box when i get back from this deployment. I don't know how much i'll need for my house so things like buying/finding a good 350 block Vs. using the 305 that i've got now for my FIRST complete rebuild, economically makes the most sense for me in this situation. Done the whole heads/cam/opti etc on my old 97 Z but never just pulled an engine and tore it down completely and rebuilt it. Im extremely excited about doing it and seeing(for fun) just how far i can get (HP/TQ & ET's)with a budget built 3rd gen L03 build.

Again, thanks!


Rob

robertfrank

iTrader: (27)

Personally to me it's not an L03 anymore once you slap a carb on it. If you really want to do a Budget build here are a few cheap options to consider.

To get all the carb stuff for it to work right if buying new your looking to spend close to 600-1000 dollars, meaning carb, intake, distributor ,regulator and what not. Even then you'll lose a good bit of mileage and driveability,although I know you can tune a carb to get "ok" mileage.

Or....... You can keep the stock heads because really they can handle 300 horse power with alittle cleanup. The 081's have been proven that they really don't surpass the 187's till after 5000 IIRC. A good set of valve springs and a timing chain will run fairly cheap. Also tuning stuff can be had for less than 200 bucks if you get just the basics. Get an 93-95 LT1 cam (1993-1995 Y-body, F-body: 202/207 0.450/0.460 lift 116 LSA )as it was the largest of the LT1 cams. The production LT4 was alittle larger. (1996 Y-body, F-body LT4: 203/210 0.476/0.479 lift 115 LSA)

The stock tbi unit can handle I believe about 330hp with the Ultimate tbi mods. So lets break it down alittle bit.

600 to 100 dollars for a gas guzzling basically unreliable pig
or I would say 300 to MAYBE 700 dollars for a streetable, fairly reliable Fuel injected machine. Me personally I'd take the latter of the two.

Rob 97 Z28

iTrader: (3)

See the car was already "shade tree mechanic" touched. guy i bought it from said there was a prob w/the TBI and computer...so what did they do, ripped it all out. They put a Holley carb on it and "called it good".So its already carb set up. Since I have had it I've put on an Edelbrock card and performer intake. So theres no spending cash on a carb or intake for it.

wow, didn't not know that at all. Good stuff


Cool, already have a new timing set on order, valve springs'll be next along with lifters and pushrods.

Does anyone know, if i put an LT1 cam in can i just go and buy off the shelf PR that are for the same year LT1 car that the cam came out of? Or is there to big of a difference with LT1 valvetrain geometry Vs SBC I valvetrain geometry?


Thanks

Rob