FYI:
Had the heads checked for flow, they flow like a "chevy injector". I had a sneeky suspicion that they were junk. Having them ported and polished to help increase flow. Should see some small increase. Also thinking real hard about having the entire motor balanced. Its not even close from what I hear. After reading transmission post I think my next move is going to be to have it reworked!!!! You know these trucks can get expensive.

------------------
Andre Terranova (1-18-1947)<*(((><
isa4325@flash.net / "1-BAD-TK" Texas Tag,
Red Lightning / Red Premier Tonneau Cover,
Red Shadow Cowl Cover / SuperChip,
3:73 Gears / K&N Filter,
Edelbrock muffler, Interceptor,
Laptop Computer at Side,
G-Tech,
Best Time 12.986 @ 107.54 "Tweeked to the Max".
[05-11-1999 #1132]


"Only Little Boys Wear Bow Ties"

 

isa4325,

Do you have any actual flow numbers for the heads? That data would be very interesting.

------------------
00 Red L on order.
98 Red Dodge V10 4X4 quad cab.
96 Yellow Corvette LT1.
92 Aquamarine Supra Turbo.
99 Arctic Cat ZR440 sno pro.
98 Polaris Super Sport 488.
97 Seadoo HX.
96 Polaris SLX w/PSI triple pipes.
97 Banshee completely tricked.
96 Polaris Scrambler.
87 Polaris Indy 600 SKS w/SLP 707 full mod.
RC CARS: Associated; RC10B3's, RC10T3, TC3. Lossi; XXCR Kinwald, XX4. Yokomo; MR4TC

 

I guess that brings me back to the question of the navigator 4v heads. From previous posts I gather that they dont fit because they are too tall and that interferes with the packaging of the supercharger. But, would they fit if the supercharger wasnt involved?

 

My understanding (and I could very well be wrong here) is that with a forced air system (super or turbo charger) that head flow isn't near important as it is on normal aspirated engines. I agree it would help some but not near the diffence it makes on a normally aspirated engine.

But then again I might be wrong..
Brad

------------------
* 99.5 Black Lightning
* Factory CD Changer
* Class 3 Towing Hitch
* Factory Tonneau Cover
* 8" Bazooka Tubs
* Kenwood 80 watt *2 amp
* 50% Window Tint
* Viper 550 Alarm w/ remort start
* 98 Yamaha Banshee w/ Toomey T5 Chrome pipes often found in the bed..

Injection is nice, but I'd rather be blown. 99 Lightning, the best of both worlds!

 

I've seen that also. The supercharger will overcome restrictions in the intake.

 

I too am a little surprised at the fact that they claim the heads don't flow well. Flow well compared to what? All 99 Mod motors got major head revisions. That is the main reason the 99 GT runs 13s stock. The heads on our trucks are very close to what you can buy from Motorsport for the 4.6. And yes, head flow is not as crucial on a blown application, but even still, less restrcition is more power

------------------
SAL
13.35@103mph
All stock with PSP 99 Lightning Chip and Filter Kit

Power Surge Performance--- Your SOURCE for SVT Lightning EFI Tuning and Performance!! http://members.aol.com/NLOCsvt/svt.html

 

Hi Guys,
If you have gone to the trouble to remove the heads to flow test them,it is not a bad idea to do the porting and polishing. On a supercharged motor it is the exhaust side that is the most important. Also a good time to do the header swap with some nice port matching.
Hey! Andre how about some photos with the motor opened up. I also liked your 1-BAD-TK gif.

------------------
BABolt
SVT#290



[This message has been edited by BABolt (edited 02-10-2000).]

 

True!, True!, and True. Head flow is not as critical in a blown motor but it will help. These things are so finely tuned that there are few things one can do for HP increase. I want to get all I can from it in its stock form first. Ports matched to headers, and intake. All ports polished and obstructions cleared. I bought a new set of heads to do this testing on and will have them installed when finished. I still think I might have the motor torn down and balanced at this same time. AT that point I will post photos.

------------------
Andre Terranova (1-18-1947)<*(((><
isa4325@flash.net / "1-BAD-TK" Texas Tag,
Red Lightning / Red Premier Tonneau Cover,
Red Shadow Cowl Cover / SuperChip,
3:73 Gears / K&N Filter,
Edelbrock muffler, Interceptor,
Laptop Computer at Side,
G-Tech,
Best Time 12.986 @ 107.54 "Tweeked to the Max".
[05-11-1999 #1132]


"Only Little Boys Wear Bow Ties"

 

Guys, you're only half right about flow not being as important on pressurized applications. On the intake side, really all you want from the port space is decent plenum volume, so in the respect you're right.

HOWEVER, exhaust flow is CRITICAL on anything with a power adder because while getting the good stuff into the cylinder isn't that hard, getting it out - because of all the extra flow WITHOUT the benefit of super-radical camming - is a real monkey strangler.

If you're going to mess with the heads and have a limited budget, gasket match the intake and spend every penny left over on the exhaust side.


------------------
Later!
Jeff S.
President, National Lightning Owners Club - http://nloc.org
SVT Lightning #74 in '95
11.92@115.2 on radials, driven daily
jeff_s@nloc.org or fmosracing@aol.com

 

isa4325,

I'm just curious when you said the L head flows like a "chevy injector", what exactly does that mean? I also found it interesting that you said you had a sneaky suspicion that they were "junk" and then you went on to say that you are having them ported and polished and you "should see some small increase". Well, if the heads are indeed "junk", then shouldn't porting and polishing them result in an incredible increase in horsepower and performance? And then you also went on to say that you want to have your entire motor balanced and "its not even close from what you hear." (who did you hear that from). Well, if that indeed was the case then wouldn't all the lightnings have severe balancing problems resulting in such things as possibly broken crankshafts or other major mechanical failures that do indeed occur when a motor truly is not even close to being balanced?

I'm not trying to be a flamer or anything like that. It just seems to me that you may be listening to people trying to perform mods on your L and they may be providing you with biased information attempting for you to purchase their modifications. Be very careful about peoples performance claims, don't get caught up in their marketing world.

You have proven to have an outstanding running L, with very little "aftermarket" equipment which indicates you definitely know what you're doing. It would be a shame to see you lose any performance after having other mods done. Believe me, I've seen it many, many times where someone has there vehicle modified and it performs worse than prior to the mods. Sorry for the long post.

 

Peter B
No flame taken. The only reason I agree with little increase is because of the blower. Most engines with blowers will overcome any week head flow, but port and polished will HELP. I am not being sold but I am checking all these items my self and due know what I am looking at. The engine is not very balanced, this comes from checking the vibrations at different RPM's. They do need a good balance job if we are going to push them with over 100 HP NOS shots. I have already seen what a 150HP NOS shot will do to a 99.9 Lightning, BOOOOM! A truck from the San Antonio area. Chevy Injectors in my experience flow about like my garden hose, low preasure, poor asperation. "Just a pun on my part" I also do believe that we will be hearing of some of these motors coming apart if pushed hard at high RPM's. They will not take it for the long haul. Remember they are factory built, not race built,.
Hope this explains my reasoning some, and FMOS, there will be a new set of headers installed, and the old stock exhaust look will have to go also.

------------------
Andre Terranova (1-18-1947)<*(((><
isa4325@flash.net / "1-BAD-TK" Texas Tag,
Red Lightning / Red Premier Tonneau Cover,
Red Shadow Cowl Cover / SuperChip,
3:73 Gears / K&N Filter,
Edelbrock muffler, Interceptor,
Laptop Computer at Side,
G-Tech,
Best Time 12.986 @ 107.54 "Tweeked to the Max".
[05-11-1999 #1132]


"Only Little Boys Wear Bow Ties"

 

isa4325,

Glad to hear no flame taken, as I wrote the post, I was worried about how bad it must be sounding, but I just had some serious questions. Very interesting points you made, I had no idea that the motors may have a balancing prob, I really figured that with a high performance vehicle such as the L, they would spend plenty of R&D time and money to ensure that would not be the case.

Anyhow, I am absolutely most impressed with the performance gains you have obtained from your L with the things you have done. Good luck on the future mods, I'm sure you'll keep us all posted on the gains.

 

Peter B
I will be in your area on Feb 24, 25, and 26. Staying at the Farifield near airport. Playing golf thursday, goint to VMI on 28th street for a business trip. Bring a tech. with me to be trained by their staff for some things we do here at my work. Are you familiar with where I will be?

 

isa4325,

You sound like you'll be in my neck of the woods. I work off of 40th st and Broadway, just about 2 miles south of the airport. Maybe we can hook up and meet, let me know.

 

send me your email address. isa4325@flash.net