Tech / General EngineIs 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!
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!
If I get 64cc chamber heads, that will give me 10.75 compression(which is what I want).
I also want 2.02/1.6 valve size
What I don't know is what intake or exhaust port sizes to get.....
I want to run the car on the track about 3 times a year and put on about 4000km(2500 miles) a summer.
I will have the tpi on for 1 year and then get another intake(LT1, mini ram or stealth ram)
I will get 1 3/4 headers too
Any opinions on port sizes for me??
__________________ '91 GTA - 400sbc,AFR195elim,280 xfi cam,1 5/8 shorty headers and single 4", LT1 intake, 3200 stall, 3.75 gears with a ford 9" and Zex dry nitrous.
My likeing with them is that they flow more than the 195s, you'll give up a little velocity with the bigger ports so youll lose a lil down low but I think you have the cubes to make up for it and more than make up for it up top
donno what ur tryin 2 do with it tho, track only? street strip? street? what size cam you gettin? I dont think the 210s have a 64cc chamber think its 72 or 76 dont remember off the top of my head.
I wouldn't go over 200cc's if it was me. Its not worth it on the street to run larger than that, its over kill for your app.
__________________ LT1 headed LG4 305 beast! Comp Solid lifter XS-262-10S, 1.6 Roller Rockers, 10.2:1, Holley 4160 600cfm, modded Weiand 7502 intake to fit LT1 heads____ Custom cylinder head cooling. Weiand 8208 Short Water Pump____TH-350 3 series 3.73 with 2 series posi and spacer____ Hedman Hedders 1 5/8 headers and Y-pipe 3in Exhaust, Dynomax 3" Bullet muffler ____Moroso Ultra 40 Wires ACCEL HEI Super Coil ____Competition Engineering 3120 Bolt-on SFC's____Homemade: Wonderbar, solid tie rod sleeves, Aluminum LCA and Panhard Rod with spherical rod ends, alternator and PS bracket, Strut tower brace, and Decoupling torque arm with telescoping link.
3000lbs
"The liberty of a democracy is not safe if the people tolerate the growth of private power to a point where it becomes stronger than their democratic State itself. That, in its essence, is Fascism - ownership of government by an individual, by a group or by any controlling private power."
-FDR
"If this were a dictatorship, it'd be a heck of a lot easier, just so long as I'm the dictator."
-- President George W. Bush
During a photo-op with Congressional leaders on 12/18/2000.
donno what ur tryin 2 do with it tho, track only? street strip? street? what size cam you gettin? I dont think the 210s have a 64cc chamber think its 72 or 76 dont remember off the top of my head.
I would like the street-strip application the best.
Not sure on what cam I am getting until I figure out what heads I am getting.
I think that 10.75-11.0 compression is as big as I want to go.(64cc=10.75 to 1)
If you're going with an automatic transmission then your shift recovery is going to be lower in the RPM range.
You'd definately be better off with the longer runner HSR and a head with ports in the 180-200cc range.
Also keep in mind that port volume is just that. It is not a true indicator of cross-section area at any given point in the port, nor does it tell you any taper in the port.
With a 700R it's the first to second shift that kills you.
The recoveries go like this assuming no converter slip.
1st gear at 5000 = 2nd gear recovery of 2650
1st gear at 6500 = 2nd gear recovery of 3450
The rear gear or tire size doesn't matter since the transmission gears stay the same, so the spreads do not change unless you change to a different transmission.
With the 700R-4 consider a minimum of 3000 RPM stall converter neccessary. A 383 should produce enough torque to increase the shift extension to closer to 4000 RPM (increased slip).
This is the reason that the shorter runner LT1 and miniram should only be used with an automatic with a very high stall, or a manual trans. Those intakes shift the horsepower curve up higher in the RPM range. The low shift recovery of a 700R would kill your acceleration.
Since you're keeping the 700R, that's why I suggested the HSR, and even then the stall I mention above would help greatly with the 700R trans.
With the HSR and stall, you then have more room to choose for you heads intake port volume. You can better use a larger volume like the 200cc to 215cc at that point.
Going the other way with a miniram, stock converter, AND the larger intake port, you would most likely have very poor performance unless you extended your working RPM range to 7500+ RPM and/or swapped to a close geared manual trans with increased rear-gear ratio.
I hope this information helps you in putting together a better working combination.
Originally posted by 305sbc The recoveries go like this assuming no converter slip.
1st gear at 5000 = 2nd gear recovery of 2650
1st gear at 6500 = 2nd gear recovery of 3450
Feel free to do the math yourself; it's quite simple. I did state in my post about slip. When unlocked, converters have a certain amount of slip. Stock converters do not have a lot of slip. Tire and transmission slip can also be a factor during a shift.
My first thought is that you don't have tire or transmission slip, but probably the normal amount of converter slip that's in the neighborhood of about 500 RPM at the shift.
The main factor in your case is how the RPM was recorded. Going by the factory tach during a scan, or by the way g-tec reads engine speed, you're definately going to have some error. G-tec has it's own forum to address problems with their g-meters, and the reading of RPM is one of the big ones.
Your rear gear or tire size doesn't change the calculated recovery speeds. That is determined by the gear spread in the transmission.
Not trying to jack your thread but I see a few different heads have been mentioned. I know these heads have been mentioned before but has anyone ever bought a set out of curiosity?
I feel that on a 383 for the street a 200cc inlet is plenty. The SportsmanII heads are great units at a reasonable price. I am using them on my 406 and have no complaints about the way it runs. Lots of idle to upper rpm torque. Let me say again lots of torque...very important on the street. 2.02/1.60 valves are plenty, but consider using a multi-angle valve cut with a 30 degree type of job. This will give the opening valve more flow at low lifts where it spends more time than full open (did I put that clearly?) Also consider a 1.6 rocker ratio to allow the engine to think a larger cam is installed without the effects of long duration. Make sense??
----------
Wow this is from last year...I should pay more attention.
Last edited by GICATA; 01-05-2007 at 08:36 AM.
Reason: Automerged Doublepost
I closed up the ports on my AFR 195's. The velocity and swirl that I picked up worked better with the shorter rods. Peak power is around 5500rpm (430hp) and peak tq was around 4000 (470tq).
You didn't mention the cam specs. That has a lot to do with head slection. It doesn't do much goo to put a big port head on top of a cam with short duration and not much lift.
In general, if you're interested in running nitrous at the track then a larger port head is a good thing. However, it will be a bit "sloppy" on the street.
If you want the best responsiveness on the street and only occasionally go to the track and use a small shot of nitrous, I'd go with the AFR195's or even the AFR180's. The 180's will give you plenty of bottom end where you need it with the 700R4.
A good converter always helps. Again, the stall rpm will depend on cam. But I agree. Use something in the 3000-3500 range.
Put the spray on it and let it eat!!!
Heads are like women. Everybody's got their favorite type.
Again, need to know what you want to do for cam and motor performance in order to make a head and converter selection.
Having said that IMO the best heads for a hot S/S motor are AFR's. The new Elminators are supposed to be hot but I've only got experience with the older models. I have a 422 stroker with a Hyd.Roller (.525/.540, 242/252 @ .05) and AFR210's making 475rwhp. In a automatic car that's making 550-570 FWHP. So I'm believer in AFR's.
However, TFS195's are a good low cost head. If I were running a shot of spray I might use TFS215's. Also, Canfields are a good cost effective head.
Check out Popular Hot Rodding August 2004. Vizard built a 383, Hyd.FT motor w/Canfield's making 475hp. Sprayed it with a 175 shot and made 650HP.
The little 383 in my 83 TA has TFS G1's(Stock) and a little 229/234 hyd roller. It weighs 3650lbs and runs 12.40-12.50's/107-108mph on motor. That's about 360RWHP.
Then there's Brodix, Edelbrock, Dart, World.........
From my recent experience I would go with something around 210cc for your 383. We just finished the primary tune on my 355 build up with Dart Pro One 200cc heads and the Comp Cams XFI 268 cam. I'm also running 10.75:1 compression with .035" quench.
The driveability is excellant with very sharp throttle response. Idles very smoothly at 750rpm. No low end power drop at all. Now maybe the 3600rpm stall helps. I don't know but I'm very please at how well the car runs. The drivability is the best it has been in years.
__________________ Best of 11.57 and 115.73 mph(1811DA). Motor: Dart SHP block 368ci, AFR Comp 195cc heads, 11.1:1 comp, highly modified TPI 1st style SLP runners, moded GM plenum and First Injection TPI intake manifold, Mike Jones 3/4 race cam, Yank PT4000 converter, Dyno Don 1 3/4" shorty headers, Dyno Don custom exhaust, custom cold air intake, AS&M monoblade throttle body. Meziere electric water pump. Mufflex 3.5" exhaust catback. Magnaflow 3.5" muffler#12909. Kevin91Z Tune. 4L60E installed. Now 420RWHP, 417RWTQ with new motor.
Your TPI intake is going to like a different cam selection then your miniram or stealth. Also your head selection for the two style COULD be different. I wouldn't go more than 180 on a TPI motor but 195 with the miniram/stealth. You REALLY need to sit down and figure out ONE (TPI or mini/stealth)combination, then build it. Your going to eat up alot of money.
I have a converted LT1 intake, so that is the intake I will use.
I will shoot for 10.5-11 for compression.
I am going to use a 3000-3200 stall.
The cam will be will a lift of atleast .5 lift with a 1.5 roller rocker(.533 with 1.6rr)
It will have a duration of atleast 224
It will have a LSA of 110-112
I will use a 150 shot of nitrous and work my way up to a 200shot.
Has anyone tried this combo?
__________________ '91 GTA - 400sbc,AFR195elim,280 xfi cam,1 5/8 shorty headers and single 4", LT1 intake, 3200 stall, 3.75 gears with a ford 9" and Zex dry nitrous.
AFR 195... If you plot the air flow at each 0.5" increment of valve lift (up to 0.55" lift), and look at the area under the curve, you will see that the AFR 195s outflow everything else out there.
Right now, I am getting good performance on my 395 cu.in. stroker with AFR 190s. I recently ran a 12.12 with my MAFed '87 IROCZ. I'd like to upgrade to AFR 195s.
From my recent experience I would go with something around 210cc for your 383. We just finished the primary tune on my 355 build up with Dart Pro One 200cc heads and the Comp Cams XFI 268 cam. I'm also running 10.75:1 compression with .035" quench.
The driveability is excellant with very sharp throttle response. Idles very smoothly at 750rpm. No low end power drop at all. Now maybe the 3600rpm stall helps. I don't know but I'm very please at how well the car runs. The drivability is the best it has been in years.
i realize this thread is over a year old, but i am putting together a very similar combo. I going to be converting my 350 to a 383 (eagle rotator kit) and i got dart pro 1 platinum heads (200cc), and a comp XE cam 224/230 dur, 543/550 lift with 1.6 roller rockers.
my question is about the correct stall i should get. i already ordered a B&M holeshot 2400, but im wondering if i should get a higher stall. the reason i went with a lower stall is because i am plannig on taking it to the strip every once in a while, but i still want it to be good on the street. should i go higher??