Building A 306 On A Budget

[mikestang63]

it would probably be a good idea to get some new roller rockers. and i asked this on another forum but i have been getting useful information here too. so lets say i was going to go with the explorer intake, and a cam that made its power below 6,000rpm. between the AFR 165's and TFS Twisted Wedge 170's, does anyone have a preference? for a torquey, peak at 5500-ish RPM motor would one or the other work better? or are they close enough to not make a difference?

and using the TFS heads as an example, they come with a choice of a 58cc or 61cc combustion chamber, and also with either 1.46in dual valve springs or 1.47in single springs? i'm assuming with a mild motor such as the one im trying to build i'd want the 61cc combustion chamber, is this correct? and what about between the valve spring options?

Either head are great choices. The TFS new are cheaper, used about the same price. TFS heads on a stock motor- I would go 61cc and your cam will dictate the springs. The street heat heads are good for most cams up to .550 lift.

I tried and true combo is either AFR 165 or TFS 170 heads, TFS 1 cam, ported explorer intake, and Crane, Harland Sharpe or FMS rockers. Just for s and giggles I run AFR 165 heads, ported Explorer intake, TFS cam, Ford 1.6 rockers, and the other usual bolt ons like headers, MAF, 70MM TB and with a tune pulled 292 rwhp and 314rwtq through an AOD- a stick will add another 10% as AOD's are not as efficient. Add the 20% lost HP and you are at about 360 flywheel hp.

 

[revcor]

I do have a question. Why are you worried/limiting rpms to 5500? Not saying you have to have a high winding motor but 6k isn't exactly a screamer. Unless you mean make peak power at 55 and shift @6? I would go with the smaller cc head to bump compression up a little. Either head would be perfect for your build. Personal preference is TFS 170's because they have the bigger valves and can be ported later if desired. Also a little cheaper the last time I looked. I don't remember the exact specs on the springs. Talk to your cam tech and match them to the spring choice.

Well a few reasons (and yes I meant making peak power around 5500).
1) I was under the impression that once you took it much past 6000 you needed to beef up the valve train past what you might otherwise have to
2) many of the breathing related components are either advertised as designed for idle-5500, or for 1500-6500, so in the spirit of drivability I'd rather have the idle-5500 performance
3) my dad advised me that the more a motor is designed for higher rpms, the more it's low-rpm torque and drivability suffers
4) I figure the motor will last longer if I keep it to below 6k
5) as a DD it will spend most of the time at low rpms

 

[revcor]

Either head are great choices. The TFS new are cheaper, used about the same price. TFS heads on a stock motor- I would go 61cc and your cam will dictate the springs. The street heat heads are good for most cams up to .550 lift.

I tried and true combo is either AFR 165 or TFS 170 heads, TFS 1 cam, ported explorer intake, and Crane, Harland Sharpe or FMS rockers. Just for ****s and giggles I run AFR 165 heads, ported Explorer intake, TFS cam, Ford 1.6 rockers, and the other usual bolt ons like headers, MAF, 70MM TB and with a tune pulled 292 rwhp and 314rwtq through an AOD- a stick will add another 10% as AOD's are not as efficient. Add the 20% lost HP and you are at about 360 flywheel hp.

I appreciate the info! Two questions, at what rpm are those peak dyno numbers reached? And how would you describe the daily drivability of your car?
Also, for a similar motor, what would you advise for a clutch (was recommended spec or centerforce but they offer different "stages") for a car that will be drag races weekly? And how do I determine ideal exhaust sizing?

 

[mikestang63]

I'm in Texas at the moment- San Antonio to be exact and don't have access to the dyno sheet. The driveability before and after the dyno tune was night and day- primarily do to the fact it is an AOD and they act more quirkier becuase of the different EEC timing. For a clutch, those are the two I like, the stage will depend on what feel you want. I would go with a stage 2 as it gives you better clamping but still a stock pedal feel. Foe exhaust size- no need to go over 2.5 inches.

 

[revcor]

I'm in Texas at the moment- San Antonio to be exact and don't have access to the dyno sheet. The driveability before and after the dyno tune was night and day- primarily do to the fact it is an AOD and they act more quirkier becuase of the different EEC timing. For a clutch, those are the two I like, the stage will depend on what feel you want. I would go with a stage 2 as it gives you better clamping but still a stock pedal feel. Foe exhaust size- no need to go over 2.5 inches.

Where do you usually shift at? And again thanks for the info! Really appreciate it

 

[A5literMan]

Well a few reasons (and yes I meant making peak power around 5500).
1) I was under the impression that once you took it much past 6000 you needed to beef up the valve train past what you might otherwise have to
2) many of the breathing related components are either advertised as designed for idle-5500, or for 1500-6500, so in the spirit of drivability I'd rather have the idle-5500 performance
3) my dad advised me that the more a motor is designed for higher rpms, the more it's low-rpm torque and drivability suffers
4) I figure the motor will last longer if I keep it to below 6k
5) as a DD it will spend most of the time at low rpms

While I do agree in most respects to these points,there are a few that I would like to clarify. The valvetrain will be fine at 6000 rpm. The combo that Mike outlined above is a great example of a build you could model yours after. With your t5-3.73 gear don't be afraid of a "bigger" intake. The idle-5500/1500-6500 rpm debate is slightly off. If you're wanting to maximize both aspects of DD And at the strip get the higher flowing intake. Depending on the head/cam combo most of the intakes perform about the same in the lower rpm range. The differences will not be noticeable on the street but will be noticeable at the high end of the power band. For example a Systemax will make plenty of low end and probably make 10-20 more hp at the topend. The explorer intake if ported is a very good intake. I'm also not sure if the Tfs1 would pass emissions. It's a very good ots cam for streetability and performance though. Durability between a 5500 rpm vs 6000 rpm would be negligible also. Now if you were planning on going higher it would be a different story. Your build plans are very good and would be a very solid combo. You should be very happy with the outcome.

 

[revcor]

the explorer intake is looking more like a neccessity than a choice now, my budget is getting eaten up by all the littler things like TB, MAF, injectors, rockers, fuel pump, etc.

Does the brand of fuel injector matter? What about impedence?
And as for headers, what primary size should I choose 1 5/8 vs 1 3/4? I can only use shorties because of CA smog, but does equal vs unequal length make much of a difference with shorties?

 

[A5literMan]

With shorty headers it doesn't really matter for the performance is about the same as far as equal vs non equal goes. There aren't many 1 3/4" shorties available. If in the budget I'd buy them(Anderson ford has some). I think a good Pro-M -30# injector combo with a Walboro 190-255 pump would be ideal. If you end up with a h/c/i combo that is a little milder than say 375hp(flywheel) stick to 24's. You can add more press up to a point. If you're not going to get professionally tuned its a crap shoot. I think you're going to fall somewhere inbetween and would error on the big side. Rich AFR is safer than lean(obviously within reason). They have "plugins" for the ev1/ev2 inj.

 

[revcor]

With shorty headers it doesn't really matter for the performance is about the same as far as equal vs non equal goes. There aren't many 1 3/4" shorties available. If in the budget I'd buy them(Anderson ford has some). I think a good Pro-M -30# injector combo with a Walboro 190-255 pump would be ideal. If you end up with a h/c/i combo that is a little milder than say 375hp(flywheel) stick to 24's. You can add more press up to a point. If you're not going to get professionally tuned its a crap shoot. I think you're going to fall somewhere inbetween and would error on the big side. Rich AFR is safer than lean(obviously within reason). They have "plugins" for the ev1/ev2 inj.

That's the thing is I won't know how much HP it makes until it's on a dyno, and to be at that point it would need injectors in it already lol. But I doubt my combo will make 375.. I am estimating it will make around 340 at the crank based on people with similar builds usually making around 300-320 at the wheels. So near the cusp of 24lb/30lb injectors. I am going to be getting a dyno tune. I just don't want to buy injectors and have non-ideal ones, I would rather be safe than sorry if you can go a size larger with no ill effects.

 

[A5literMan]

Have you settled on the combo you're going to run? I'd have a better idea for recommendation. If you go bigger inj,and a tune, the tuner will be able to adjust the necessary fuel map etc. that's the safer way imo. The only way to adj "smallish" inj is to add fuel pressure. This is a band aid and taxes the inj/fuel system. Some people do this. I don't believe it's the correct way imo.

 

[revcor]

As of right now, i'm pretty sure i'm going with the TFS Twisted Wedge 170 heads and a ported Explorer intake. Still undecided about the cam; waiting to hear back from Ed Curtis about a custom, also considering the TFS stage 1 cam or a Comp Xe264HR if I can be assured it'll pass CA sniffer test

 

[A5literMan]

Sounds like a 24# inj would be plenty. Those darn Cali smog nazis!! Lol. Should be a very solid runner.

 

[revcor]

Yeah it's a bitch. i just need to figure out a cam and i should be ready to start spending money!

 

[revcor]

Due to a supercharger and a recent motorcycle purchase, my "acceptable" budget is also taking a bit of a hammering again.. In the time since originally posting this, I installed a Vortech V3 SCi 6psi kit on the current motor to hold me over while I save up more money and do more research. My plan is to build the motor like mentioned above (Twisted Wedge 170's, TFS Stage 1 cam, ported Explorer intake) and then also swap the supercharger onto the new motor as well. If that combo NA would make around 350hp at the crank, then a generous estimate of 100hp for the blower would put it around 450. Now that has me needing 47lb injectors, but I can't seem to find any MAF's for sale on the popular sites that come calibrated for anything larger than 30lb injectors! And is a 75-76mm MAF and 70mm throttle body still going to be sufficient?