500hp 331 with a Muthr Thumpr cam?

[cjperformance]

Everything is getting very confused in here.
I don't normally do this, so take it as a one off offer.
I'll build you a motor, in a well set up capri it'll run low 10/ high 9 passes & it'll live on the street with vigilant maintenence.
1 condition - I draw up the combo, in discussion of course, but a plan is made & it doesn't change.

Given you can run up to 354 cubes & engine bay space in a capri is generous (I had one) I'd go for a 351w style block with chi 3v heads, single carb chi intake, solid roller cam with endurance lobes & pressure fed lifters.
Bore at 4.125, stroke at 3.25 with a nice long rod.

Time frame would be 3-4 months as I'm busy & just booked in another 3 builds last week.

This is a good offer. Tony is a straightup good honest professional custom engine builder. 110% attention to detail.

[fomocosteve]

This is a good offer. Tony is a straightup good honest professional custom engine builder. 110% attention to detail.

I seriously considered Tony's offer Back in August when he made it, and had a chat with Tony on the phone, He know's his stuff, and you don't have to do much of a google search to see some fantastic custom work in engine fabrication that he is capable of. Though a couple of thing's to consider for me, is 1. I already had some parts that made it easier to stick with the Windsor headed platform, and 2. That this is a bit of a journey for myself, I want to learn and apply, and stuff up if I must a bit myself. I want to know why the parts are there in the engine, I want to learn and have the knowledge and not just say I forked out $XX,XXX to such and such who did it all for me. Call me stubborn, but part of the fun of building this car is learning, applying and creating the heart of the beast, And I thank Tony and all others who have helped me gain knowledge, even when I may have disagreed at times, in hindsight, I think I've come a bit of a way and would agree with what I may have once disagreed with.

[steve316]

The more you know the more you have to learn. Ignorance is bliss, 40 years ago I was very happy, now happy about half of the time.

[fomocosteve]

The more you know the more you have to learn. Ignorance is bliss, 40 years ago I was very happy, now happy about half of the time.

Aint that the truth, that's why I keep asking for people to highlight where I might be making a mistake... I'm trying to get this one as good as possible on the first shot... Ive spent the last few months gathering info... though it's difficult on the net as there is so much bad info out there, It's great to have a place where people actually know what there talking about...

[fomocosteve]

Okay, I have a question for anyone who can help, I know it depends on the camshaft profile, though Is a 7800 rpm max rpm point going to be Okay with the following if the camshaft was taken into account.. .600 - .650 lift solid roller, 2.08 ferrea hollow stems (154grms) or manley severe duty (124grms) inlet valves, tool steel retainers, ? spring pressures based on cam. Will the lighter valves and tool steel allow running up to 7800 on a semi regular basis, or where seems to be the cutoff rpm for valvetrain reliability when using lighter valves and retainers. I haven't been convinced with conical springs, but what I did read was based on singles, mabe double conical springs would be an advantage? .... Thoughts?...

[steve316]

Lighter valves will increase the life of your springs. A good spring 200 to 240 on seat will allow you to turn 7800. light weight retainers locks and newer light weight springs all add up higher rpm capabilities and longer spring life. Any money spent on better valve train components is money well spent. Good luck

[fomocosteve]

Okay, a cam that's come up on my radar is the 40350925 - Lunati grind,

Cam Style: Mechanical roller tappet

Basic Operating RPM Range: 2,800-7,500

Intake Duration at 050 inch Lift: 257

Exhaust Duration at 050 inch Lift: 265

Duration at 050 inch Lift: 257 int./265 exh.

Advertised Intake Duration: 288

Advertised Exhaust Duration: 296

Advertised Duration: 288 int./296 exh.

Intake Valve Lift with Factory Rocker Arm Ratio: 0.668 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.668 in.

Valve Lift with Factory Rocker Arm Ratio: 0.668 int./0.668 exh.

Lobe Separation (degrees): 109

Intake Valve Lash: 0.018 in.

Exhaust Valve Lash: 0.018 in.

This looks like a Mcdonald's camshaft, cos I'm lovin it.

[Caprimaniac]

Hello, Steve.
I haven't followed this thread from start to finnsh, so i just recently figured your
goal was a 10- sec Capri MK1 302- based car.

What I can provide is a spec-list as I happen to have such a car.
My Capri was NOT ntended to go to the strip at all. Road-racing was the goal, but different haps and mishaps made me give it a go at the strip, and I've stayed there for a few years now.

Quick list:
347 small bore
All off the shelf parts (some home porting of vic jr heads) Lunati voodo SR. SPEEDTALK- approved parts list. Sort of.
Home- built/ assembled
Weight is 1100 kgs with driver and fluids.
T-5 (a-5) transmission shifting above 70000 (pita with a synced)
10.5 /26" rear wheels, 3.75 Atlas axle

A good friend has a MK1 too.... His ONLY goal was a 10 sec pass.
Engine from a US builder with help from a shop here in Norway too.
331 solid roller, shifting below 7000 (although the cam will rake him past 7500...)
Car is very close to mine, but a bit heavier, 8.8 axle, amongst some other things.
He has not made his goal after 4 years.....
That might be due to a too small 650 carb. Too early shifting. Or other things...

My advice to you if you want tu use the car alot on the street is;
Go the biggest cubes available and put a good effort in getting the
Exhaust as quiet as possible minimize ressonance. You need 2x 2.5"

If you send me a pm, i'll send you the parts list or even post if here if you so desire. (Heck- i might have posred it on here before....somewhere.)

RS

[fomocosteve]

Hi RS, not really what I'm after, but thanks for your reply, Glad your enjoying your Capri
Steve.

[fomocosteve]

I'm thinking the Lunati grind will make peak at 7000, and that their rpm range is the peak RPM. I'd be happy with that. My estimate with 11.5 compression would be 590-600hp @ 7000 rpm. I'd be happy at 550, though I think it could be more. Proof will be on Dyno Day. I think this is the one.
Steve.

[Calypso]

I'm thinking the Lunati grind will make peak at 7000, and that their rpm range is the peak RPM.
Steve.

My friend ran very similar Lunati SR, except it was 106LSA. It made max.hp (somewhat above 530) at ~7200, if I recall. Torque graph was flat as a pool table. (347W, 4.030 bore, afr205, super vic. out of the box).

You have less stroke, more bore, perhaps a little less head (~30hp?), wider LSA, possibly better ring seal from the block, tunnel ram? I'd say you'll have to zing it higher to make the max. Definitely above 7000. I think 590-600 sounds optimistic, but I've been wrong before.

Looking forward to see how it does.

[fomocosteve]

Actually, looks more like 580hp @ 7000, The dynamic comp was too high @ 11.5:1, the cam needs around 10.7 by the look of it to run with premium pump, though I'll have to get the cam timing to calculate it properly. I don't want a race gas only car.

[fomocosteve]

My friend ran very similar Lunati SR, except it was 106LSA. It made max.hp (somewhat above 530) at ~7200, if I recall. Torque graph was flat as a pool table. (347W, 4.030 bore, afr205, super vic. out of the box).

You have less stroke, more bore, perhaps a little less head (~30hp?), wider LSA, possibly better ring seal from the block, tunnel ram? I'd say you'll have to zing it higher to make the max. Definitely above 7000. I think 590-600 sounds optimistic, but I've been wrong before.

Looking forward to see how it does.

I have seen in a Dyno proven ford performance book the XR292r Comp cam dyno at 531hp @ 6800 with a 750 holley and Vic Jr. Possibly 550 @ 7000 with a T/ram. I'm probably being optimistic. Here's the Comp XR292r specs...

Cam Style: Mechanical roller tappet

Basic Operating RPM Range: 3,200-7,200

Intake Duration at 050 inch Lift: 254

Exhaust Duration at 050 inch Lift: 260

Duration at 050 inch Lift: 254 int./260 exh.

Advertised Intake Duration: 292

Advertised Exhaust Duration: 298

Advertised Duration: 292 int./298 exh.

Intake Valve Lift with Factory Rocker Arm Ratio: 0.621 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.627 in.

Valve Lift with Factory Rocker Arm Ratio: 0.621 int./0.627 exh.

Lobe Separation (degrees): 110

Intake Valve Lash: 0.016 in.

Exhaust Valve Lash: 0.018 in.

[Calypso]

My friend ran very similar Lunati SR, except it was 106LSA. It made max.hp (somewhat above 530) at ~7200, if I recall. Torque graph was flat as a pool table. (347W, 4.030 bore, afr205, super vic. out of the box).

You have less stroke, more bore, perhaps a little less head (~30hp?), wider LSA, possibly better ring seal from the block, tunnel ram? I'd say you'll have to zing it higher to make the max. Definitely above 7000. I think 590-600 sounds optimistic, but I've been wrong before.

Looking forward to see how it does.

I have seen in a Dyno proven ford performance book the XR292r Comp cam dyno at 531hp @ 6800 with a 750 holley and Vic Jr. Possibly 550 @ 7000 with a T/ram. I'm probably being optimistic.

I'm not really claiming that hp as gold standard. Some pro's really know how to extract HP from relatively mild sounding combos. We seem typically to come a little behind here overseas near the Russian border. My intention was more to give an idea to estimate where the cam might be for a 347.

[fomocosteve]

The XR cams line have been mentioned and recommended to me earlier in the piece. In fact the XR292r might be a better overall cam choice than the lunati, as it appears more streetable. Funnily enough I have been offered a 750 DP proform Drag series carby and a Victor Jr for a really good price as well.
I think the lunati is a great cam, even for the street, though with my 1.65 rockers I'd be at almost .690" and I think that is probably too much for the street.