Need help modifying my engine
Thread Starter
Junior Member
Joined: Sep 2000
Posts: 77
Likes: 0
From: Bartlett IL
Need help modifying my engine
I have a 92 Z28 L98. Right now it is basically stock with the excepiton of the exhaust and ignition. I have a set of edelbrock heads (6085) and need to build my engine from there. What would be the best set up with these heads as the starting point, what kind of manifold, cam, and etc. Thanks for your help.
Aaron
------------------
1992 Z28 25th anniversary edition
Stock L98 with Proflow muffler and Accel ingition coil
Aaron
------------------
1992 Z28 25th anniversary edition
Stock L98 with Proflow muffler and Accel ingition coil
Member
Joined: Jun 2000
Posts: 308
Likes: 0
From: Croydon, PA, USA
Well I have the heads too and I like them but people say that they can be ported more to flow better, so I would suggest that first. Then an Edelbrock intake and ported and port match that to the heads and match the gaskets to both of them.
Next you need aftermarket runners. This depends, I think IMHO, what cam you want.
**NOTE: The springs on the heads are good to a lift of .560 then coil bind can occur. I called Edelborck up and asked. ***
If the cam is mild(durations up to 210*) then you would want to go with Large Tube Runners (LTR's) to keep the low end torque.
If you are going with a more aggressive cam like a LT4 HOT CAM (simular to ZZ9) or durations > 215* I'd say AS&M siamese runners or go the cheap way and get SLP runners (cost ~$270) and remove the seperator in them so you can get to the uppper rpms(6000 or more, maybe) of where these cams can go and still make power.
If you go with the more aggressive cam you'll need a custom chip! Not a off the shelf chip like JET or HYPERTECH! This will cost starting at $350.
If you plan on upgrading to a miniram or superram then you should decide on a specific cam for those type of plenums. I say this cause a miniram responds slightly better to a dual plane cam profile, meaning 2 different durations for intake and exhaust.
The superram responds slightly better to a single plane cam like Accel/Linfelter 219/219 cam, same durations for intake and exhaust.
I don't see in your signature that you have headers, so I woud recommend some SLP 1 3/4" headers too. You could get edelbrock TES headers but alot of people complain about them not flowing as well as SLP's. this is understandable since the tube size is smaller but I think it has to do with the rest of the exhaustbut that is what I think. I have no problem but with mine but then I have a dual exhaust.
Of couse you got the centerbolt valve covers so you need roller rockers that fit under them.I got the Crane Gold RR at a cost of $300! But I know there are different RR out there you can use but I don't know who's they are. Oh you'll need non-self aligning roller rockers on these heads. Hopefully someone will help you on this.
Hope this helped.
Good Luck!
------------------
89 IROC 350 Auto
MSD 6AL
Custom DUAL Exhaust
Edelbrock Performer 6085 Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
And Free mods.
(stock intake, runners and suspension)
13.879 @ 98.90 mph (with 2.77 gears!)
Moderator of http://www.iroczone.com
Next you need aftermarket runners. This depends, I think IMHO, what cam you want.
**NOTE: The springs on the heads are good to a lift of .560 then coil bind can occur. I called Edelborck up and asked. ***
If the cam is mild(durations up to 210*) then you would want to go with Large Tube Runners (LTR's) to keep the low end torque.
If you are going with a more aggressive cam like a LT4 HOT CAM (simular to ZZ9) or durations > 215* I'd say AS&M siamese runners or go the cheap way and get SLP runners (cost ~$270) and remove the seperator in them so you can get to the uppper rpms(6000 or more, maybe) of where these cams can go and still make power.
If you go with the more aggressive cam you'll need a custom chip! Not a off the shelf chip like JET or HYPERTECH! This will cost starting at $350.
If you plan on upgrading to a miniram or superram then you should decide on a specific cam for those type of plenums. I say this cause a miniram responds slightly better to a dual plane cam profile, meaning 2 different durations for intake and exhaust.
The superram responds slightly better to a single plane cam like Accel/Linfelter 219/219 cam, same durations for intake and exhaust.
I don't see in your signature that you have headers, so I woud recommend some SLP 1 3/4" headers too. You could get edelbrock TES headers but alot of people complain about them not flowing as well as SLP's. this is understandable since the tube size is smaller but I think it has to do with the rest of the exhaustbut that is what I think. I have no problem but with mine but then I have a dual exhaust.
Of couse you got the centerbolt valve covers so you need roller rockers that fit under them.I got the Crane Gold RR at a cost of $300! But I know there are different RR out there you can use but I don't know who's they are. Oh you'll need non-self aligning roller rockers on these heads. Hopefully someone will help you on this.
Hope this helped.
Good Luck!
------------------
89 IROC 350 Auto
MSD 6AL
Custom DUAL Exhaust
Edelbrock Performer 6085 Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
And Free mods.
(stock intake, runners and suspension)
13.879 @ 98.90 mph (with 2.77 gears!)
Moderator of http://www.iroczone.com
Thread Starter
Junior Member
Joined: Sep 2000
Posts: 77
Likes: 0
From: Bartlett IL
Would it really be worth it to get these heads ported, and how much do you think it would cost? I live in the NW suburbs of Chicago and if anybody knows of where I can get it ported and polished for a decent price that would be great. Thanks again.
------------------
1992 Z28 25th anniversary edition
Stock L98 with Proflow muffler and Accel ingition coil
------------------
1992 Z28 25th anniversary edition
Stock L98 with Proflow muffler and Accel ingition coil
Member
Joined: Jun 2000
Posts: 308
Likes: 0
From: Croydon, PA, USA
Can't help you of where to go them ported but it would help.
The edelbrocks flow somewhere close to 236 cfm.
AFR's (The BEST) flow out of the box at 267 cfm!
They say you can port the Edelbrocks to close the AFR's flow numbers.
I forget the the lift the AFR's flow at but the Edelbrocks flow 236 at a lift of around .450.
I think the AFR's flow 267 at a lift > .500 but < .550 but I'm not sure.
Is it worth it??
What so you want to do to the car? Daily driver and weekend warrior? Or just street racer and track?
With the right combo you can get the Edelbrock heads, without addition porting, on a engine into the high 12's. And still be a good daily driver. It is up to you to decide.
Good Luck!
------------------
89 IROC 350 Auto
MSD 6AL
Custom DUAL Exhaust
Edelbrock Performer 6085 Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
And Free mods.
(stock intake, runners and suspension)
13.879 @ 98.90 mph (with 2.77 gears!)
Moderator of http://www.iroczone.com
The edelbrocks flow somewhere close to 236 cfm.
AFR's (The BEST) flow out of the box at 267 cfm!
They say you can port the Edelbrocks to close the AFR's flow numbers.
I forget the the lift the AFR's flow at but the Edelbrocks flow 236 at a lift of around .450.
I think the AFR's flow 267 at a lift > .500 but < .550 but I'm not sure.
Is it worth it??
What so you want to do to the car? Daily driver and weekend warrior? Or just street racer and track?
With the right combo you can get the Edelbrock heads, without addition porting, on a engine into the high 12's. And still be a good daily driver. It is up to you to decide.
Good Luck!
------------------
89 IROC 350 Auto
MSD 6AL
Custom DUAL Exhaust
Edelbrock Performer 6085 Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
And Free mods.
(stock intake, runners and suspension)
13.879 @ 98.90 mph (with 2.77 gears!)
Moderator of http://www.iroczone.com
Thread
Thread Starter
Forum
Replies
Last Post
NinjaNife
Tech / General Engine
27
Aug 23, 2015 11:49 AM