Search



Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine
Register Forgot Password?

Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by Weld Racing
Click Here

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 07-21-2002, 11:04 AM   #1
Junior Member
 
Join Date: Dec 2000
Location: Chattanooga, TN
Posts: 91
Car: 1984 Z28
Engine: 350ci

Classifieds Rating: (0)

engine vacuum with comp 270 magnum

I've been looking at many websites and magzines for a future build-up for my car. I ran across a 355 on the AFR website that looks sweet. Basic rundown of the engine:
AFR 190 heads
RPM type manifold
9.5:1 compression
comp 270 magnum cam (224* int/exh @ .050 .470" lift 110*LSA)
1 5/8" headers
etc.
My question is about the cam. It's a bit bigger and has a tighter LSA than I'd like for idle/vacuum. I currently have an L-82 cam (yeah, i know it sucks) i my 350 with similar duration numbers and it doesn't give me enough vacuum at idle to run my power brakes very well. I was also looking at an XE 262 cam also from comp that has slightly less intake duration to help that out. Surely several people use these cams, what kind of vacuum numbers do they put up?
Black 84 Z is offline vBGarage Page   Reply With Quote
Old 07-21-2002, 11:25 AM   #2
Senior Member
 
Join Date: Mar 2002
Location: Coushatta LA
Posts: 266

Classifieds Rating: (0)
I have put together two 355 chevys using stock vortec heads,the XE262H cam and a rpm intake. I love this combo for the street, slight lope at idle, good vacuum, excellent drivability. I personally saw this combo run 14.20's in a 4000lbs trk with 3.42's and slicks and a stock converter. The AFR 190 heads you mentioned are hard to beat.

Lonnie
boogie is offline vBGarage Page   Reply With Quote
Old 07-21-2002, 01:57 PM   #3
Senior Member
 
Join Date: May 2001
Location: Vilonia, AR
Posts: 615
Car: 84 Z-28 Camaro
Engine: 383
Transmission: T-56
Axle/Gears: richmond 3.73, eaton posi

Classifieds Rating: (0)

I have a comp 280H in mine and I pull 14 inches at idle and my brakes work fine
__________________
84 Z-28 in the prosess of re-build:
383, steel crank, forged pistons 4 bolt block .040 over
comp cams nitrous XP 288HR
Adv dur 288/315
Dur@.050 236/248
LSA 113
valve lift .520/.540
"quiet" gear drive
polished and ported trick flow 23* heads
comp P/N 26918-16 beehive valve springs
steel full roller rockers
edelbrock pro-flow 1000 CFM EFI port mached to heads
Venom 36 lb injectors
edelbrock nitrous sys, 150 shot
hooker 2210 1 3/4 pri headers
powermaster starter
powermaster alternator, 160 amp
'97 T-56 transmission
centerforce dual friction clutch
pro 5.0 shifter
richmond 3.73 gears
eaton posi
spohn K-member
spohn "wonderbar"
spohn torque arm/crossmember
spohn lower control arms
spohn A-arms
spohn panhard bar
spohn subframe connectors
dual exauast, 3" up to cut outs
nordskog digital dashbord
trippel gauge pilar mount
digital fuel press.
digital nitrous pressure gauge
digital oil temp gauge

84 Z-28 350 is offline vBGarage Page   Reply With Quote
Old 07-21-2002, 02:35 PM   #4
SSC
Supreme Member
 
SSC's Avatar
 
Join Date: Jul 2001
Location: Pueblo Co
Posts: 3,974
Car: No more birdy

Classifieds Rating: (0)

I used the 270H's in 3 of my 350's the last couple of years, there great for power but economy will suffer. The highest vacuum I could pull at idle was 10/11in with a conservative timing setting. Down the road in cruise it will pull around 17/18in of vacuum, not too bad but that equals around 12-14 MPG more 12 then 14. Power brakes work fine but under a fair amount of heavy accelration then braking they get touchy.
__________________
1976 SWB C10 3/4 drop, gen VI 454/M3.
1973 Buick Apollo wifes play car. Chevy 383/S3.
SSC is offline vBGarage Page   Reply With Quote
Old 07-21-2002, 02:35 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine

Tags
270, 270h, 288, 350, 355, 383, 84z, brakes, cam, cams, comp, edelbrock, idle, magnum, magumn, power, run, xe
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 12:57 PM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
All content copyright 1997 - 2014 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details