1.70 vs 1.72 Roller Rockers

[Strype]

Engine Combo Help Please!!!

1.72's I've got brand new

Will these work with my B-cam and GT40 X (1.94, 58cc) heads I just ordered??? I'm using stock length Roller lifters and stock rods and I'm wanting to bolt on to a stck motor


EDIT: Just talked with a guy at CJ Pony Parts and he said that the1.72's I ordered from them may be too much for the pistons??? He said I may have to use shorter rods or cut the pistons Talked to Ford Racing Hotline and they said the same thing... maybe he though I said E cam????


Soooo... I'm FREAKIN OUT!!! Has anyone again, put 1.7's, a b-cam, and GT40 X heads on their stock motor before

 

[Strype]

just called Ford Racing Hotline (586) 468-1356.


They told me that I CANNOT use my 1.7's with the b-cam Did he think I said "E"? Anyone know?


Great... now what. I guess I have to ship the 1.7's back and wait and wait and wait for the backordered heads to come in

This is getting rediculous.

 

[JChalfan]

Nevermind... just called Ford Racing Hotline (586) 468-1356.


They told me that I CANNOT use my 1.7's with the b-cam


Great... now what. I guess I have to ship the 1.7's back and wait and wait and wait for the backordered heads to come in

This is getting rediculous.

I asume the issue is piston to valve clearance? Can you return the 1.7's and just pick up a set of 1.6 RR's?

Jeff

 

[Strype]

I asume the issue is piston to valve clearance? Can you return the 1.7's and just pick up a set of 1.6 RR's?

Jeff

Yeah- exactly. The problem is my heads are still on back order too. I'm just gonna cancel the heads, send back the stupid roller rockers and go somewhere else.

 

[GT_Rich]

1.7's won't work with the B-cam? I've read on here many people using 1.7's with the b-cam or even the e-cam (which has more lift). I have a set of twisted wedges with 1.72 ford rockers and the b-cam that I'll be putting in this winter. I'll have to keep an eye on this post b/c I swore that 1.7's and the B was no problem.

 

[5ive.oh]

I called FRPP and they told me I could run the B or E cam on my GT40's with 1.7RR's. But unless you got a great deal on those parts you would be better off with some AFR 165's

 

[Strype]

I called FRPP and they told me I could run the B or E cam on my GT40's with 1.7RR's. But unless you got a great deal on those parts you would be better off with some AFR 165's

Hmmmm... that's funny. I'm wondering if it's because the GTT40 X's are 1.94 and not 1.90-

Does anyone out there know? Pleeeeeeeeeeeeeeeeeeese

 

[JChalfan]

I ran 1.7 RR's in a '94 Cobra motor with E303 cam. The pistons and heads (GT40) were stock, and I think the RR's were the stock cobra ones.

My memory's a bit hazy, but I thought stock GT40 heads (like the ones on a 94 cobra) had 1.84 intake valves.

Jeff

 

[8950HO]

Did you consider going with the Trick Flow top end kit?

 

[Reed]

If you take a look at Ford's two GT40 crate engines (http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=7368) they use a B and an E cam with GT40x cylinder heads.

They list part number M-6564-B351 for the RRs that they use in either version of the engine (http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=634) which are 1.6 RRs. Just thought I would let you know what Ford is using in their own engines, hope it helps!

 

[Strype]

I ran 1.7 RR's in a '94 Cobra motor with E303 cam. The pistons and heads (GT40) were stock, and I think the RR's were the stock cobra ones.

My memory's a bit hazy, but I thought stock GT40 heads (like the ones on a 94 cobra) had 1.84 intake valves.

Jeff

Yeah- that's the GT40 P... it's a different head. I think that's why I got mixed up too

Did you consider going with the Trick Flow top end kit?

Too late now. But I really didn't want to go Trick Flow. On Horse Power TV the numbers sucked.



I really need to know if anyone has this combo

 

[ratrapp2]

i've got the gt-40x(64cc)with a b-cam.i switched to 1.72rrs with no problems except having to get a set of fms valve covers to clear the rrs.the car definitly ran better.it's worth it in my opinion.unless you have so some massive pistons or serious cutting of the block or heads you should be okay.it made me decide to definitly change to a bigger cam this winter.

 

[millhouse]

Yeah- that's the GT40 P... it's a different head. I think that's why I got mixed up too




Too late now. But I really didn't want to go Trick Flow. On Horse Power TV the numbers sucked.



I really need to know if anyone has this combo

Ahh…I see your problem. Your watching Horsepower TV again and actually believing them! Seriously, were you not aware that the show mentioned is fiction?

I am curious though as to what kind of numbers they pulled. I'd venture to bet it's 30-50 h/p below the norm.

The guys in the below link have had favorable results with the TFS top end kit and a dyno tune.
http://forums.stangnet.com/showthread.php?t=559655&highlight=trickflow+results

 

[MAC'n89Blckstng]

1.72 maybe too much for the heads. GT40's dont flow past .500 lift, I have an E303 cam and my total lift with my 1.7's is .529. I was told to put 1.6's on the intake and leave the 1.7's on the exhaust and I should see a bigger power increase.

 

[8950HO]

Too late now. But I really didn't want to go Trick Flow. On Horse Power TV the numbers sucked.


What were the HP TV numbers like?

Trick Flow advertises 350 HP at the crank for the top end kit with the street heat intake I believe.
Factor in a 15% drivetrain loss and you`re at 297 rwhp roughly.

 

[superhuaman]

im running the gt40 alum heads (not gt40x) with 1.94/1.54 valves, an e cam, 1.7 crane/ford oe roller rockers, on a 306 with stock cr and speed pro forged pistons with valve reliefs. i havent had it way way up in rpms yet since i havent even driven it...but it seems to be alright.

 

[04sleeper]

You will be just fine with the B cam and 1.72's.

 

[rickd93_lx]

i own a 93 cobra it has 1.7 crane rr and a bcam and i have no problem with clearance. i belive the bcam or a cam with very similar specs was stock in the cobra, IMO the 1.6 rr are better as it will allow you a larger selection of cams with out clerance problems.

 

[Tonys96Cobra]

Aliate X has the TFS kit and swears it pulls harder than his stock motor with a 120 shot. I just put a set of Pheads from tristate (1.92-1.54_ 5angle, swirl polished under cut stems with stock cam, 1.7's and FRPP headers, the thing runs really, really well. The heads are $540 I think. Look into it, it will save you bucks..