Section162

Hello,
Can anyone comment on the Ramjet intake? It seems like hardly anyone is using it. I searched the boards and found part #'s, hood clearance info, etc., but no real after-the-fact results. I understand that I might need to change some wiring connectors and move some sensors around. The car is a 90 so there's no MAF. I burn my own chips, so I'm not really worried about tuning. Current setup is in sig.

Will I lose low end torque? Gain top-end? I want to try this, but any comments/speculation/hard data that anyone could offer would be greatly appreciated!

APACHE JOHN

Working on it not done yet. With a wife and kid it could take awhile. LOL the car is a 1991 Z28 I have not driven it since 1998.

Abubaca

iTrader: (3)

I think it's a safe bet that your gonna probably lose a small amount down low, and gain a lot up top. It's very similar to the stealth ram if I'm not mistaken as far as performance.

....do a search for ramjet.

...on another note, not to hi-jack the thread, how does your car perform now? Your car is almost exactly what I have planned. I have the SLP 1.75 headers and a 2200 stall with a 3.27 ready to go in. I have the ZZ4 cam too. I was gonna swap in some pro-toplines vortechs with the SDPC and some hi flow LT runners. You can PM me with your response if ya want.

Brett H. - 89GTA

I've been interested in this intake too...I'm hoping the hood clearance for my GTA would be an improvement over what I'd get with the StealthRam.

89 Iroc Z

I think this intake is a great intake. The GM ramjet engine which has iron vortec heads peaks at 5200 rpms. I bet with aluminum fastburn heads and this intake it would give great power to upper 5000's.

89 Iroc Z

Here is the dyno chart of a GM ramjet engine. From here:
http://www.hotrod.com/techarticles/113_0307_ramjet4/

89 Iroc Z

Here is a dyno of Scoggin-Dickey vortec TPI engine with the following setups.

This is NOT Ramjet Dyno Numbers! (This is a test of a few TPI combinations for comparison to the ramjet numbers)

Test 1: is a stock L98 350ci short-block with iron Vortec heads, a factory L98 hydraulic-roller cam (see the “Cam Specs” chart for details on all the cams), the Scoggin-Dickey base, stock TPI runners, plenum, and throttle body. The exhaust used open 1-7/8-inch headers.
Test 2: was the same engine with a ZZ4 hydraulic-roller cam and LT4 valvesprings.
Test 3: added a set of Edelbrock runners and throttle body along with a GM Performance Parts HOT cam and 1.6 roller rockers.
http://www.chevyhiperformance.com/techarticles/56858/
http://www.chevyhiperformance.com/te...58/index1.html
http://www.chevyhiperformance.com/te...58/index2.html
http://www.chevyhiperformance.com/te...58/index3.html
http://www.chevyhiperformance.com/te...58/index4.html

My vote is on the ramjet intake.

EDIT: It should be interesting when someone gets some dyno number on the holley vortec stealth ram.
Also the ramjet engine, which is dynoed above has a smaller cam then the ZZ4 and LT4 Hot cam which are test 3 and 4. Here are the ramjet cam specs (14097395)::
camshaft lift (i/e): 0.431" / 0.451" hydraulic
cam duration (i/e): 196 / 206 degrees @ 0.050 lift

Section162

Thanks for the replies!

I'm very impressed with the Ramjet torque and horsepower curves posted above. I didn't realize that the HP peaked at 5200.

The three CHP tests are also interesting. They went from a stock L98 cam to the Hotcam, but the peak HP rpm didn't change? It stayed around 4700-4800 on all 3 tests. I think GM rates the ZZ4 engine's max HP at 5250rpm. And the Hotcam's peak should be much higher.

For what it's worth, in first gear, my car seems to pull pretty strong to 5500rpm, but in 2nd and 3rd, it really seems to struggle at 4900-5000 or so. This could be my imagination, but it's more likely the "wall."

If nothing else, the Ramjet intake seems to match my cam better than the TPI does.

Section162

I don't mind posting some info; it might be useful for others who are reading. Basically I got WOT timing and fuel in the chip to where I thought it was close, and made one run on my G-Tech.

60' ---------- 2.257
1/8mi ---------- 8.869 ---------- 83.4mph
1/4mi ---------- 13.633 ---------- 104.2mph

As I understand it, that MPH is good for low 13's? I have NO drag racing experience, and I was sliding around and back-pedalling trying to get traction off the line LOL. Otherwise, it runs very well, very smooth and lots of throttle response.

89 Iroc Z

I also wanted to say there are a few things that are very important to note about the above dyno results:
- The ramjet create engine comes with a small cam. It is smaller then the ZZ4 and the LT4 HOT cam.
- In the Scoggin-Dickey vortec TPI dyno’s, Test 2 & Test 3 both had bigger cam’s then the ramjet engine.
- The ramjet engine seem’s to have the same power down low if not better then the vortec TPI
- If you buy the ramjet intake separately from GM it really isn’t very pricey. You can also pick up a used LS1 TB for about $40 on ebay which is what the ramjet intake uses.
- A ramjet intake with a bigger cam and some nicer heads like E-Tecs or Fastburns could easily make in the 400Hp+ range.

Another good thread with tons of part numbers and information: https://www.thirdgen.org/techbb2/sho...hreadid=245843

Section162

Well I've made up my mind - I'm making this my winter project. Time permitting, I'll start ordering parts next week.

While the intake is off, my friend thinks we should swap in a bigger cam. Tempting, but then it wouldn't be a fair before/after comparison of the intakes, which I'd like to see just for my curiousity. Maybe a cam swap later on? Right now, the chip probably isn't optimized, but oh well.

I'm gonna try to report back this spring/summer. Hopefully a good report from the butt-dyno, and more MPH in the quarter.

Anyone done an intake-only switch from TPI to Miniram? To Stealth Ram?

Brett H. - 89GTA

APACHE JOHN

My Vortecs are ported with bigger springs. I have a LT4 hotcam and Hooker LT's. Also a T56 and 3.42's. If I don't like the 3.42's I'll move up to 4.10's. Your dyno wasn't complete the stock Ram-Jet makes almost 400lb of torque at 1600 rpm's. That's not loosing low end torque at all. Hopefuly the Hot Cam will move the this torque peak up. I would perfer a more LS1 type powerband.

D's89IROCZ

The TPI doesn't allow the rpm's to get much into the 5000 rpm band. I had mine all ported (check my www.)...just to make it flow to the 5500 rpm's that the ZZ4 camshaft makes power to.
These are some great posts !

contactpatch

.
360 HP, is impressive, from a system with a intake cam
duration of only 196.

89 Iroc Z

Well I decided to make a table of ramjet cam sepcs and a few vortec heads. It really shows how much power the ramjet intakes makes off such a small cam and okay flowing heads. A big cam and a set of E-tecs or fast burns would make some pretty killer power I would assume.

Heads table:
(scroll way down I am not sure why this board software does this)
<table border="1">
<tr>
<td width="125">Manufacturer<br>
<br>
Head Type<br>
<br>
Valve Sizes
</td>
<td width="85" align="center">
Edelbrock
<br>
E-Tec 170<br>
<br>
Aluminum<br>
<br>
1.94/1.50
</td>
<td width="85" align="center">
Edelbrock<br>
E-Tec 200<br>
<br>
Aluminum<br>
<br>
2.02/1.60
</td>
<td width="100" align="center">GM Fast Burn<br>
<br>
<br>
Aluminum<br>
<br>
2.02/1.60</td>
<td width="110" align="center">
GM Vortec L31<br>
<br>
<br>
Cast Iron<br>
<br>
194/1.50
</td>
</tr>
<tr>
<td width="125">Chamber Size</td>
<td width="85" align="center">64cc</td>
<td width="85" align="center">64cc</td>
<td width="100" align="center">62cc</td>
<td width="110" align="center">64cc</td>
</tr>
<tr>
<td width="125">Intake Runner</td>
<td width="85" align="center">170cc</td>
<td width="85" align="center">200cc</td>
<td width="100" align="center">210cc</td>
<td width="110" align="center">170cc</td>
</tr>
<tr>
<td width="125">Exhaust Runner</td>
<td width="85" align="center">70cc</td>
<td width="85" align="center">78cc</td>
<td width="100" align="center">78cc</td>
<td width="110" align="center">&nbsp;</td>
</tr>
<tr>
<td width="125">
See Footnotes:
<br>
Flow Int/Exh @
</td>
<td width="85" align="center">*9<br>
</td>
<td width="85" align="center">*9<br>
</td>
<td width="100" align="center">*2<br>
</td>
<td width="110" align="center">*6 and *7<br>
</td>
</tr>
<tr>
<td width="125">0.100</td>
<td width="85" align="center">64/54</td>
<td width="85" align="center">67/57</td>
<td width="100" align="center">62/55</td>
<td width="110" align="center">70/49</td>
</tr>
<tr>
<td width="125">0.200</td>
<td width="85" align="center">130/104</td>
<td width="85" align="center">122/110</td>
<td width="100" align="center">136/104</td>
<td width="110" align="center">139/105</td>
</tr>
<tr>
<td width="125">0.300</td>
<td width="85" align="center">186/140</td>
<td width="85" align="center">175/153</td>
<td width="100" align="center">187/133</td>
<td width="110" align="center">190/137</td>
</tr>
<tr>
<td width="125">0.400</td>
<td width="85" align="center">220/169</td>
<td width="85" align="center">223/182</td>
<td width="100" align="center">232/158</td>
<td width="110" align="center">227/151</td>
</tr>
<tr>
<td width="125">0.500</td>
<td width="85" align="center">232/183</td>
<td width="85" align="center">252/196</td>
<td width="100" align="center">266/180</td>
<td width="110" align="center">239/160</td>
</tr>
<tr>
<td width="125">0.600</td>
<td width="85" align="center">238/190</td>
<td width="85" align="center">259/204</td>
<td width="100" align="center">275/193</td>
<td width="110" align="center">229/162</td>
</tr>
<tr>
<td width="125">0.700</td>
<td width="85" align="center">&nbsp;</td>
<td width="85" align="center">265/207</td>
<td width="100" align="center">&nbsp;</td>
<td width="110" align="center">&nbsp;</td>
</tr>
</table>

Footnotes:
*2 -- These flow numbers come from Pace GM Parts.
*6 -- From Paul Shufelt
*7 -- From Chevy High Performance Feb. 2001
*9 -- From Edelbrock's Site
Data from: http://purplesagetradingpost.com/sum...fo/heads1.html




Cam Table:
<table border="1">
<tr>
<td width="65">Cam</td>
<td width="35" align="center">&nbsp;</td>
<td width="65" align="center">Duration<br>
advertised<br>
(degrees)</td>
<td width="65" align="center">Duration<br>
@ 0.050<br>
(degrees)</td>
<td align="center" width="55">Lift<br>
1.5<br>
(inches)</td>
<td align="center" width="55">Lift<br>
1.6<br>
(inches)</td>
<td align="center">Lobe Separation<br>
angle (degrees)</td>
</tr>
<tr>
<td width="65">L98<br>
Corvette</td>
<td width="35" align="center">Int.<br>
Exh.</td>
<td width="65" align="center">&nbsp;</td>
<td width="65" align="center">202<br>
206</td>
<td align="center" width="55">0.403<br>
0.415</td>
<td align="center" width="55">0.430<br>
0.443</td>
<td align="center">115</td>
</tr>
<tr>
<td width="65">Ramjet<br>
Create</td>
<td width="35" align="center">Int.<br>
Exh.</td>
<td width="65" align="center">228<br>
308</td>
<td width="65" align="center">196<br>
206</td>
<td align="center" width="55">0.431<br>
0.451</td>
<td align="center" width="55">0.459<br>
0.480</td>
<td align="center">109</td>
</tr>
<tr>
<td width="65">ZZ4 Hyd.<br>
Roller</td>
<td width="35" align="center">Int.<br>
Exh.</td>
<td width="65" align="center"><br>
</td>
<td width="65" align="center">208<br>
221</td>
<td align="center" width="55">0.474<br>
0.510</td>
<td align="center" width="55">0.506<br>
0.544</td>
<td align="center">112</td>
</tr>
<tr>
<td width="65">LT4 Hot<br>
Roller</td>
<td width="35" align="center">Int.<br>
Exh.</td>
<td width="65" align="center">279<br>
287</td>
<td width="65" align="center">218<br>
228</td>
<td align="center" width="55">0.492<br>
0.492</td>
<td align="center" width="55">0.525<br>
0.525</td>
<td align="center">112</td>
</tr>
</table>


Ramjet Specifications:
Displacement: 349.7 ci
Bore: 4.00-inch
Stroke: 3.48-inch
Compression ratio: 9.4:1
Block: Cast-iron, two-bolt main
[b]Cylinder heads: Cast-iron Vortec with 1.94/1.50-inch valves; 63cc chambers
Crankshaft: Cast-iron one-piece rear-main seal
Connecting rods: 5.7-inch forged powdered metal with 3/8-inch bolts
Pistons: Cast aluminum
Camshaft: GM PN 14097395 hydraulic roller; 196/205 degrees duration at 0.050-inch tappet lift, 0.460/0.481-inch lift (with 1.6:1 rockers)
Rocker arms: 1.6:1 roller
Timing chain: Single roller

Section162

The L31 head is kinda weak on the exhaust side, especially as shown by comparing both the 170cc heads above. For anyone interested in porting vortec heads, I found this article to be very helpful -

http://www.carcraft.com/techarticles...rt/index1.html

Also Vizard's HOW TO BUILD MAX PERFORMANCE CHEVY SMALL BLOCKS ON A BUDGET has specific pages dedicated to porting vortec heads, and several other heads as well.

APACHE JOHN

Yep the exhaust is weak but fixable....and the intake #'s are very acceptable. A killer head with just a little work. Zero deck the block etc. I can't wait! I'm hoping for 400hp at the crank so what 340 or so at the rear wheels?

Section162

Here's a Ramjet parts list:

http://www.gmpartsdepot.com/pdfs/SB_RJ350.pdf


Here's a good Ramjet thread:

https://www.thirdgen.org/techbb2/sho...hreadid=209325


A couple of articles:

http://www.gmhightechperformance.com...htp_realworld/

http://www.carcraft.com/howto/56398/

Section162

Based on what I've been reading, this *adjustable* fuel pressure regulator fits the Ramjet:

http://216.242.145.16/products/product.phtml?p=13

It even mentions the ramjet crate motor on the web page. This is Aeromotive PN 13106 from the LT1 vette (not f-body).

Section162

Since the ramjet has no provision for a MAT (manifold air temp) sensor, it needs to be relocated. I have the SLP CAI, and right now I guess I'm planning on moving it to the plastic tube that goes from the air filter housing to the throttle body, hopefully with a bung of some sort. I searched for pics of relocated MATs, but didn't come up with much.

Ideally, the chip should be modified to account for the drop in temperatures that the MAT will now be seeing.

Here is one of *several* relevant posts from the DIY-PROM board:

https://www.thirdgen.org/techbb2/sho...hreadid=173101

Section162

Sorry it's taken this long! Can I ask how far along you are? Just wondering what you might be doing with throttle cable, fuel lines, etc.

89 Iroc Z

About the parts needed for anyone interested, if you already have a TPI setup now this is what you need to buy to switch to ramjet is the following:
- Obviously vortec style heads
- 12489371 Ramjet intake manifold
-17096144 Throttle body or you can just pick up a cheap used LS1 throttle body off ebay, much much cheaper then buying one new from GM
- 12553918 Fuel Rails
- 16249939 Map Sensor, or hookup the stock sensor to the intake if you have SD already
- 17123897 Fuel Pressure Regular

APACHE JOHN

On a camaro use a V6 air cleaner top housing they had the provision for the MAT.

APACHE JOHN

I have almost everything. I am going to use a cable from a 98 up LS1 car (same throttlebody). In the process of the lines right now. If I wouldn't have had so many other project this would have been done. I've only started the Ram-Jet part about 6 months ago.

APACHE JOHN

Lokar lists the same part # on the LS1 throttle cable and the Ram-Jet cable. The V6 air cleaner top I have is from a '89 and the MAT srewed right in just lengthen the harness. I made a plug in jumper harness.

Section162

Maybe this is obvious, but apparently there are several other used throttle bodies that will work with the ramjet besides the LS1.

According to this thread (long but also has other good information), the TB from a 4.8, 5.3 or 6.0L vortec truck engine from 99+ pickups/suburbans is recommended:

https://www.thirdgen.org/techbb2/sho...threadid=47200

Depending on what parts list/web page I looked at, I saw two different TB part #s listed for the ramjet: 17113520 and 17096144. (I don't know what the difference might be.) On gmpartsdirect.com it looks like both are currently available. The local dealer here told me that that second TB goes on various 96-99 trucks with the 7.4L engine.

For an LS1 TB, another good place to look might be the classified ads section of LS1.com.

ChevelleFan

iTrader: (4)

Reviving an old thread here...

In looking at those part numbers above, the fuel rails are really the deal breaker --- $325! At $400, the manifold isn't a bargain, but not bad. The throttle body can be had for $50 on ebay, the regulator can be had from an LT1 Vette -- that just leaves the rails as the main component that's missing.

The regulator has been mentioned to be from an LT1 Vette. GM is famous for their parts-binning. Do those rails resemble anything else that might be production?

-Dave

Section162

Not to my (limited) knowledge. Have you considered building your own rails? I thought I'd read about folks doing that for not a lot of money. Might try a search - especially on the alternative intake board.

HTH

Section162

Since this thread just got revived, for anyone that might be interested, I thought I would post an update on this project.

I swapped cams and assembled everything last summer. Car runs well part-throttle, but I didn't get a chance to do much tuning. When spring gets here, I will be taking pics and posting more info regarding fuel lines, pigtail connectors, and other parts that I used in the swap.

I will be swapping from 3.23 10-bolt to 3.73 9-bolt, and upgrading to an aftermarket fuel pump this spring before doing anything else. Then I fully plan to have some results (G-tech or track) next summer after some tuning. Then there's the SFC's, LCA's and adjustable brackets that are also laying around. Just wish I had more TIME to get to this stuff LOL.

ChevelleFan

iTrader: (4)

Yeah, keep the updates coming. Your comments have made me curious about how hard it would be to modify and existing set of rails.

In this thread, https://www.thirdgen.org/techbb2/sho...t&pagenumber=1
there is a pic of the ramjet from the rear that I think shows the rails could be easily substituted with cheaper aftermarket rails. The rails themselves seem very similar to what's on my Stealthram -- for which the rail kit w/ non-adjustable regulator is only $130 from Summit.

The retaining bolts go through, perpendicular to the injector openings. I could see adding a -6AN adapater at the rear of the passenger rail and the return line off the regulator on the driver's side -- just like my Stealthram rails.

It's looking very do-able. It just too bad you never see these intakes used on ebay.

-Dave

kmath

iTrader: (1)

I've had this setup for two years now,I used the gm rails as opposed to trying to modify other things,I was interested in asthetics as well.I've never dyno'd the set up but in the 1/4 mile I managed a 12.66 at 108mph.Shifting at 6600rpm (stock bottom end).that's with the stock rear end a 9 bolt 2.77 gears.

slohand

kmath,

need more info. exhaust? chip? anything you would be willing to share. i am in the process of deciding on stealthram or possibly ram jet.

i bought a superram only to find out it will require mods to put on with vortec heads. :-(

thanks!!

kmath

iTrader: (1)

I am using the iron vortec heads with a three angle valve job,crane gold roller rockers,K-motion springs and a crane cam(rough idle)Edelbrock shorty headers.Hooker Aerochamber muffler W/a single tail pipe,stock computer with the power chip,had the rev limiter eliminated.

slohand

Thanks K,

are you using 1.5 or 1.6 rockers? what stall are you running?

and, i'm i understand you have a custom chip? if so was it a guess or did you have anyway of measure the changes form the chip? (not familiar with "power chip")

how does your cam measure up to the lt4 hot cam?

2.5 in or 3.0 exhaust?

did you have a chance to see the article where they ran a 12.3 with the stealth ram?

D's89IROCZ

Geese I wish they didn't have emmissions up here , it would be fastburns and the ramjet . I just didn't like the down sides of a Super Ram so I went with a ported/siamesed Edlebrock TPI setup .Does it ( Ramjet)have a provission for the EGR ?

Stingray69

APACHE JOHN

http://www.rossmachineracing.com/extrusion.html... has a much better deal. And if give them the specs they will drill and machine them for you.