SBF ? 4" vs 4.1" stroke

Buddy is building a new SBF. TFS high ports, hydraulic roller, street/strip....he's wondering if he should do a 427 or 438 and why? I say the bigger cubes but that HP would be similar on either one. Any drawbacks?

Appreciate any feedback.

windsor wrote:Buddy is building a new SBF.  TFS high ports, hydraulic roller, street/strip....he's wondering if he should do a 427 or 438 and why?  I say the bigger cubes but that HP would be similar on either one.  Any drawbacks?

Appreciate any feedback.

The drawback may be who is making the cranshafts and is journal overlap needed for the potential power output.

windsor wrote:Buddy is building a new SBF.  TFS high ports, hydraulic roller, street/strip....he's wondering if he should do a 427 or 438 and why?  I say the bigger cubes but that HP would be similar on either one.  Any drawbacks?

Appreciate any feedback.

The heads are in my opinion a good match for the 427 .
The heads on the 438 may be a little small, but will still make good power.

What is the rest of the specs for the engine build ?

TEA TFS 225 highports(58cc)
matched super Vic
11.1:1 CR pump gas
aftermarket block, H Roller cam (specs TBD but prob low 250's I, high 250 low260's E/ .660-.690 lift)
1-7/8 to 2" step headers
950-1050 4150
c4 with UCC 4900 stal
3260#'s
27x10.5 QT pro

Looking to be 630-650 HP on 93. Car sees street time (50/50), Not worried about extra torque because of the tire. Which motor should I build?

427 I feel would work best with the heads, compression and headers you have .

windsor wrote:TEA TFS 225 highports(58cc)
matched super Vic
11.1:1 CR pump gas
aftermarket block, H Roller cam (specs TBD but prob low 250's I, high 250 low260's E/ .660-.690 lift)
1-7/8 to 2" step headers
950-1050 4150
c4 with UCC 4900 stal
3260#'s
27x10.5 QT pro

Looking to be 630-650 HP on 93. Car sees street time (50/50), Not worried about extra torque because of the tire. Which motor should I build?

I just don't understand why everyone thinks a Hyd roller is so great? if you want to make power get that compression up and put a camshaft in it that will make the grade....

I hear you but the thing is street driven a LOT. Driven to track, etc. Needs to be pump gas.

Currently a 10.90 car.

windsor wrote:I hear you but the thing is street driven a LOT.  Driven to track, etc.  Needs to be pump gas.

Currently a 10.90 car.

I have run solid roller and solid flat tappet on the street with pump gas 393W.

Make the best of what you have !

Used to be a SFT....but yes, he's definitely staying HR and pump gas.

I vote the 427 too.... well the cam not so much just not a big fan of h/r cams

HR stuff works fine as long as you use good quality lifters.

windsor wrote:I hear you but the thing is street driven a LOT.  Driven to track, etc.  Needs to be pump gas.

Currently a 10.90 car.

The HR is ok but 4900 on the converter is not really very street friendly, is it going to be a NOS motor.

Converter is ok for him. It's a UCC and drive able.

Small shot only, mostly NA.

FalconEh wrote:

windsor wrote:I hear you but the thing is street driven a LOT.  Driven to track, etc.  Needs to be pump gas.

Currently a 10.90 car.

The HR is ok but 4900 on the converter is not really very street friendly, is it going to be a NOS motor.

It depends on what you call street friendly ! I have run as high as 5500 stall 8" converter on the street doing the 30 mile cruise with NMRA  as well as driving to school 35 miles one way.

whitefield wrote:

FalconEh wrote:

windsor wrote:I hear you but the thing is street driven a LOT.  Driven to track, etc.  Needs to be pump gas.

Currently a 10.90 car.

The HR is ok but 4900 on the converter is not really very street friendly, is it going to be a NOS motor.

It depends on what you call street friendly ! I have run as high as 5500 stall 8" converter on the street doing the 30 mile cruise with NMRA  as well as driving to school 35 miles one way.

I have street'd 5500 but anyone who has done it would not call it street friendly street-able yes, street friendly no. A new Boss mustang with a kit is street friendly, a big stall is not the same as side stepping a clutch IMO

FalconEh wrote:

whitefield wrote:

FalconEh wrote:

windsor wrote:I hear you but the thing is street driven a LOT.  Driven to track, etc.  Needs to be pump gas.

Currently a 10.90 car.

The HR is ok but 4900 on the converter is not really very street friendly, is it going to be a NOS motor.

It depends on what you call street friendly ! I have run as high as 5500 stall 8" converter on the street doing the 30 mile cruise with NMRA  as well as driving to school 35 miles one way.

I have street'd 5500 but anyone who has done it would not call it street friendly street-able yes, street friendly no. A new Boss mustang with a kit is street friendly, a big stall is not the same as side stepping a clutch IMO

I guess it all depends on the person and there preference !

What rear gear ratio is he running ?

3.89 gear.

Yes, each person's definition of what's tolerable on the street is different.

Really, just looking for input on the 4 vs 4.1 inch strokes for this application and its intended use.

how come people always come here for small block advise? and not a small block sight? I am just curious....

That's why I put it in the general section and not engine tech. I've asked tons of BBF questions but I trust opinion on this site and am only a member on YB otherwise.....

It clearly says SBF in the thread title, so I guess you could ask the question about why you decided to click on it ol' Cougy.

the Coug wrote:how come people always come here for small block advise? and not a small block sight? I am just curious....

Coug most on here started with a small block of some sort ! So therefore for the most part there are some good or better advise than on the other sights .

You haven't been around in a while so you must be trying to get your post count up !

whitefield wrote:

the Coug wrote:how come people always come here for small block advise? and not a small block sight? I am just curious....

Coug most on here started with a small block of some sort ! So therefore for the most part there are some good or better advise than on the other sights .

 You haven't been around in a while so you must be trying to get your post count up !

I know most on here ran small block I have myself and still have a bunch of them just curious is all....
Whitey my post count is no matter like some of the local blowers who say a lot of nothing to just see their lips move... and ramble a lot about nothing...

Whitey my post count is no matter like some of the local blowers who say a lot of nothing to just see their lips move... and ramble a lot about nothing...


LOL ! 10-4 ROGER THAT

I made the mistake of asking a sbf question on a regular Ford site once and every answer I got was from some keyboard warrior that read this and some magazine did that, ebay is the best place to buy parts and Pro Comp is the shit. Of course there is some generalizing in that response but that was the jist of it. I ask my sbf questions here because you so get reliable answers from people that have actual experience building Fords. There may be a lot of BS on this site most of the time but there is a shit ton of very knowledgeable people here that will do their best to give you quality answers when asked.


IMO Bruno should just add another group for non 460 engines because non 460 questions are quite common.

jasonf wrote:I made the mistake of asking a sbf question on a regular Ford site once and every answer I got was from some keyboard warrior that read this and some magazine did that, ebay is the best place to buy parts and Pro Comp is the shit. Of course there is some generalizing in that response but that was the jist of it. I ask my sbf questions here because you so get reliable answers from people that have actual experience building Fords. There may be a lot of BS on this site most of the time but there is a shit ton of very knowledgeable people here that will do their best to give you quality answers when asked.


IMO Bruno should just add another group for non 460 engines because non 460 questions are quite common.

X2...............

Now to the op's question, with his intended usage, (STRIP STREET) and a hydraulic cam. I have built windsors with a 400 m crank turned down to a chevy 2.100 rod pin and made close to 675 hp with it and ran it 5 years.

With the 3 inch main over lap is good and the 4.1 in a good 4340 deal is not a problem.

And with the intended use the TFS High ports will support the extra 10 cubic inch no trouble and make the engines rpm range slightly lower.

1.51 rod stroke ratio not a problem either.

Stick it in and enjoy the torque increase. You won't hook it on the street with either one but it will show up on the track in 60ft.