85vette-84vette

I read on another forum that just by porting the stock crossfire intake manifold will put an 84 vette in the high 13 seconds in the 1/4 mile. Isn't a stock crossfire in the 15 .5 second range? Just a port job drops it by 1.5 seconds? Has anyone achieved this? I would of though it would take a cam and heads and maybe some NOS to do this on a crossfire?

Demonic85

Umm I think it will take more than just porting the intake, but yes it is a significant improvement for the crossfire. Just the port and some drag radials would probably show some 13's. There's a member on here, I think CFI-EFI has a modded '84 that runs 13's.

corvetteronw

I was cruising the vendor area at Bloomington Gold last summer and saw this guy sitting at a table with a beautiful cross fire display. I understand that he has a good reputation in the Chicago area.
Dan's Carburetor Service. Dan Squires e-mail danscarbs@comcast.net, phone: 630-408-2743.
You might want to give him a jingle.

rodj

Posts # 10 -20

http://www.smokinvette.com/corvettef...ad.php?t=19966

ps374

The stock Crossfire manifold starves for fuel. Thats the way GM built it. There are two schools of thought to get that much needed fuel. Porting or Xraming. Xram is a little more complicated IMO. To get the best benfit out of the Xram a larger cam should be used along with different heads. Wealand who orginal designed the Xram promises 50 extra horses with just the manifold exchange?

CAJUN C4

I was the 2nd owner of an X-Ram back in 99'.. Pat Oney is the owner out of Houston,Tx..
I agree with ps374 I don't believe you would get 50 HP unless you did the Cam,Heads, Bored TBI's (750 CFM) etc. My 84' had a ZZ4 Engine (355 HP Rated with a Carb.)with Bored TBI's, an 8746 Updated ECM and I could beat stock LT1's

see www.x-ram.com

qws

I was reading that thread the other day on smokinvette.
Don't know what the gains are on porting the intake but with just the xram install I did see a gain of 36hp at the wheels. In my photos you'll find the dyno graph.

What I think was missed on that thread was the fact the CFI did port the hell out of the intake, but does also run a 2600 stall, with dual exhaust. But I do believe thats all he has done to it. I can definetly see getting into the 13's with that combo.



So in comparison ,my X-ram increased 36 hp at the wheels and the renegade increased 33 hp. Both are close and I'm sure a home ported cfi would be about the same maybe a bit more or less. All depends on the person doing the port job.
I want to see more testing before I would buy the renagade. Just like the offy,xram,sy1 I'm sure they would all perform better on a 383 than a 350. And in order to get any of them the perform absolutely perfect on the 350 would mean that you need to tune it. IMO, any of the aftermarket intakes on the stock 350 will adjust your A/F enough to need it tuned. Don't just jump on the band wagon and buy one until you see exactly what it can do. I'm sure it will do well, just like any of the other ones do on a 350.

tpivette

doing nothing more than simply porting a stock crtossfire vette's intake manifold will NOT get you into the 13s

theres a member on here that claims 13s on a "stock motor", but that really means an untouched long block (rotating assembly, heads, cam), not a totally stock motor

13s comes in the form of a heavily ported intake manifold, true dual exhaust from the manifolds back, a 2600 stall, and a set of drag radials. that got him 13s i believe, but i dont know the mph. mph is indicative of power production, E/T is relative of how well you put that power to the ground

JD'S WHITE 93

Jim's car does have full length headers a converter and a heavily ported intake and it does go 13s. The converter is helping a great deal i agree. The intake alone won't get a L83 anywhere near 13s.

rad928music

I'd start with the rear gearing first, i bet you could run in the 14's with just a gear change and not hurt you much in driveabilty.
Then intake porting can only help.

I'd post in the tech section and i bet you get allot more help.
good luck

pologreen1

M.J.L.

The stock L98 can run 13.9 with 235 hp. I think the crossfire with some minor mods could do that as well. People just give it a sucky reputation because it was not a factory hotrod.

ps374

A lot of Corvette owners love beating up on the Crossfire. Why , Im not sure. I think part of the problem is MANY 84s are beat, have not been maintained and run like crap. So when they wont ever brake the tires , they are labeled dogs. My 84 with Xram set up has no problem lighting up the tires, yet I have know other crossfire Corvettes that wont because they are in need of maintenance. The previous owner of my 84 who built it (My cousin) claims TPI Corvettes were never a problem to beat. Its time the crossfire myth was put to rest. Its dependable, economical and just as reliable as any newer C4 and once allowed to get some fuel just as fast as its TPI brothers.

JD'S WHITE 93

http://www.gmhightechperformance.com...tte/index.html


Here's one that broke into the 13s then 12s and now 11s

blkvette85

http://www.gmhightechperformance.com...tte/index.html


Here is the GM Tech artical.

tpivette

i would love to see someone take an 84' and mod it... adding of course dyno and track progress to the write up. recently, i was in the market for a daily driver, and a cheap C4 was considered. i eventually found a very inexpensive 3rdgen fbody and purchased that, but i wouldve loved to grab an 84' and tried to wring the most out of it. seems most owners do a few boltons and thats about it, with no real track times or dyno numbers to support the gains of each performance upgrade

however, stock for stock, mod for mod, a L98 vette will outperform a Xfire Vette every time. a simple intake porting, again, will not bring the 84's performance up to par with the 85 - 91

Paul Workman

Dom posts here sometimes but you can find him most often on the ZR1 Net Registry as "XfireZ51" Dom ported and tuned his 84 and got some astounding results at the track. Ya might wander over there and send him a PM. Dom is a heck of a guy, and I know he'd be happy to discuss it w/ ya.

P.

ps374

Paul some guys just hate this car and facts wont change their opinion.

Demonic85

I just dont like TBI, has nothing to do with the crossfire itself. I feel that there are more advantages to going carb or full fuel injection. Also, the crossfire is pretty much the same 350 engine just a different style intake.

Tom400CFI

That statement has already been disproven many times. A simple intake port job (a proper one, not the "port match" that MOST CFI port'ers do) will put an '84 slightly better than an '85. I believe the "better" part is due to the shorter runners.