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Discussion Starter #1
The 5.0 is done and in, and it runs faster than the 289 before no doubt, but something's not right still. I think it's the intake, it's got a aluminum(ford) 4v manifold and a carter 600, I think it's not tuned right at all. Im also running stock manifolds to 2" pipe back to flowmasters so there might be another problem. I am saving up money and here are the questions/upgrades I need advise on. Manifold, I'm pretty sure from what I've read the Air Gap RPM is quite an awesome "street" manifold with power everywhere, might compliment my F303 cam well. Carb, I was first thinking about the grant 650 street demon but then I saw the holley 670 street avenger and it is also cheaper and has supposedly better performance. Then onto headers, I'm redoing the whole chassis/exhaust next so I am going to 2.5" piping and some nice headers, here's the kicker though. I've heard "full length" headers have ground clearance problems and you have to go over speed bumps and whatnot carefully. Would Tri-Y's better for my "street"/strip/mean daily driver application? If so what size collector 2.5 or 3" and I'm hopefully roadracer can make me one of those famous xpipes. Last but not least, heads, this isn't for a while but I'm not going to skimp here cause as many ppl will tell you and from what I've experienced heads can really make or break a car. I think my cleaned up stock sized valve iron heads are really holdin my engine back now actually. So I'm looking at you know Trick Flows, Edelbrocks, GT40's and then I hear everyone ranting about AFR's. Like I said I'll save up if I have to but they sound like they're really worth the $$$. Can anyone tell me 165 or 185 for a street machine that will hopefully run high 12s or 13s and make power 1500 - 6500 ?? Obviously I'm not goign to get the smog ones so take that into consideration. I just down want to "bog" the engine with too much stuff and be mismatched but I also dont want to pay $1400 for their "lowest" heads, but whichever ones will work best right!? Also I'm having to really retard my timing to get it to run w/o overheating/pinging and I think I went too high compression 10:1 and I'm running 89 now, I think I'll stay 91 from now on and maybe get some additives in there. Hopefully once it's timed right it will run better but if anyone could advise me on those subjects, intake, exhaust, and heads I would greatly appreciate it. Like I said its a solid built roller 302 with hyd. roller f303 cam and a strong bottom end, 28 oz balance. I'm shooting for about 300-350 RWHP and anything above is welcome. Thanks!
 

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1. Intake manifold - I don't have experience w/the Ford 4-bbl manifold. There might be hood clearance issues w/the Air Gap RPM. I haven't read about any noticeable difference between the RPM and Air Gap.

2. Carb - A 600 cfm should be sufficient for a five-oh engine.

3. Headers - I heard/read the same thing about full-length headers. I wanted to avoid ground clearance issues and bought Sanderson headers (P/N FF3). Can't comment on collector size difference.

4. Heads - I bought AFR 165s purchased based on HoosierBuddy's results and positive reviews in five-oh magazines like 5.0 and MM & FF. According to dyno tests, the AFR 185s are better suited for strokers. IIRC HoosierBuddy cited the selection of the combustion chamber size is important.

5. 28-oz imbalance - Did the machine shop rebalance the engine?

My engine has a similar combination (AFR 165s, Performer RPM intake, Sanderson headers, etc). I'll read your future posts w/great interest. Good luck.

I'm always learning so correct any goofs or misconceptions in my post.
 

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I think I would wait on the intake until you have a clearer picture on the heads. No use getting an intake now and find later that the peak performance between the two are in different RPM ranges. Something that will make your cast heads work great may only be marginal on your new heads. As for exhaust, shorties or try-y's up against 2 1/4 should be good enough IMHO.
For a muffler I chose the Walker super turbo over flowmaster 50's because they flow a little better and not quite as loud inside the car and they still sound good on the outside. I have no idea on a collector, but my efi said to use a 3 inch with headers.
 

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I've got the F303 cam, TFS heads, Weiand Stealth Intake (PN#8020), Demon 650, MSD. I think I could be in the 13s, maybe the 12s, with the right suspension tuning. Who knows? I may be in the 13s now. Haven't been to the track yet . . . What trans and rear do you have? I've got a C4 with a stage 2 shift and a 3.55 TSD rear.

I've got the Sanderson FF3s (1 5/8" tubes and a 2 1/2" collecter) and I can spin it up to 7k. I plan on getting rid of the Sanderson's when I can afford to, the drivers side header curves so close to the block that it's nearly impossible to tighten the bolts at the collector. . . A big PITA if you have a leak there. . .

My machinist said my compression was 9.837:1 (according to the KB piston book) but I think probably closer to 10:1 since he resurfaced 'em before assembly. No pinging. I'm running 87 octane and 34-36* total advance (can't remember exactly). I've had it up as high as 40* total advance and no pinging there either.

I think you'd be happy with the TFS Heads. Check these guys out for a good product and good prices: http://www.totalengineairflow.com/ I got the standard TFS heads and port matched them to the intake.
 

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Discussion Starter #5
Hood clearance wont be a problem, I did some pre-estimate measuring based on the specs on edeclbrock.com .. I'm already using a 1" spacer and I still have a good inch and a half when the hood is closed(playdo test). Plus I will be putting on a K&N sometime soon anways and they only make them smaller/skinnier for my size air cleaner so I might gain another half inch or so there.
600 CFM - I think if it was tuned right it would be OK for a "mild" street engine, 12 second car? I doubt it, but 650 demon or 670 holley?
AFR advise - Like I said I'm needing room to grow, eventually I'm gonna do the twin turbo thing thing on either a 351w block stroked to 393 or my 302 block stroked to 331. So I'm building it as a "base" for future upgrades.
28 oz balance - We had it balanced to 28oz because we didn't want to go to serpentine and buy new pulleys and alternator blah blah etc, I've also heard 28oz is better "performance wise".
1966conv - As mentioned above I'm building with room to grow and I DO want to match everything, that's why I'm asking if these things will go good together. Unfortunately heads are so expensive they will probably be the last of the afore mentioned but assuming my F303 cam generates power 1500 + and I've heard ppl getting them to 7000, I think a intake and head choice based solely on efficient rpm range would be better than just throwing anything on. the RPM air gap operates 1500 - 6500, good enough for me, if I go higher than that I messed up a powershift and shouldn't be driving. MSD ignition later on will fix the over-rev problem though. BTW - I've got a complete pertronix ignition now so thats not a problem. And I've heard the 185's are for 1500-6500 whereas the 165s are for idle - 5500. As for the 2.25 exhaust? All the people say backpressure this backpressure that but I would rather have a meaner tone(read 2.5") than X percent more pressure which converts to a insignificant loos of HP, plus this is going to be built up later on remember. i already know I'm using flow40's and turndown dumps cause I have em on and I love the sound, I'm young and I can stand it, but the car alarms can't.
66benchcoupe - I put in a "used" T5 with the engine, not rebuilt or anything and it's not World Class. I'm hoping it lasts until I save $2000 to put in a TKOII, it's working fine for now though. Rearend is another story, that's not going to happen for a while either, but I'll probably buy one of the complete 9" center units via M+ .. detroit locker or traction lock with lower gears. As for now it's a open 8" on 3:00 but if worst comes to worst I'll just launch at idle.
Thanks for the advise everyone!
 

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I'd advise upgrading the rear first. With a 5 speed you'll want at least 4.11 gears so you'll be able to use 5th gear on the freeway, maybe lower. Good luck!
 
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